Introduction for 620slodat and his diesel build

[620slodat]

Another question I just now thought of. Are the exhaust manifolds for the SD-22 and 25 the same size?

[620slodat]

Came up with another question, this time about batteries. My Chevy uses two batteries because glow plugs take so much power that they are like a second starter. I see you are using only one battery. Do you need a lot of amps to operate both the glow plugs and the starter?

[wayno]

I believe all the exhaust manifolds are the same, but the intakes are different, the intake holes in the head are bigger on the SD25 and so is the throttlebody/carb looking thing.

I bought gaskets for my diesel engines a long time ago, one set was from Nissan dealership, for the most part every time I have removed my intake/exhaust manifolds I have re-used the old gasket, they sell diesel gasket kits on ebay, but the headgaskets need to be bought from Nissan, as they are this sandwich metal type gasket, auto parts stores sell genaric gaskets that do not look anything like Nissan diesel headgaskets.

When I rebuilt that SD22 I have, the kit came with a gasket set, oil pump, it had everything, they do not sell what I bought anymore.

I have a lot of gasket sets in my gasket storage tub and I have a shed full of tubs, I do not recall where I bought most of them anymore, ebay, dealership, Baxters when they were still worth going to, I have not bought any diesel gaskets in years.

I do not know where that turbochager is that I took off the modified exhaust manifold, I do know it had the wastegate wired shut, the water cooling part was not connected either, I do not think they could build any reasonable amount of boost, but there could be a lot of reasons for that, too big of turbo, too many leaks in the system which it looked like it had leaks as electrical tape had been used at some of the joints.

All my turbos have water cooling, don't know a lot about this subject.

When I had that engine running with the turbo on a engine stand I could not hear the turbo spinning, while I can hear it spin on both my 720 and 521 diesels, I believe the turbo was too big and could only build 2/3psi boost, while mine have both seen 20psi at least once before I adjusted them to not go over 15psi, like I have said, I would try to find a good used 1600cc gas engine turbocharger for the SD22, I believe I used an 1800cc turbo from a AWD Subie for my SD25 and I am very happy with the result, the 720 with an SD25 has what I believe is a 1600cc gas turbo, it is smaller that the Subie turbo and the turbocharger that I took off was even bigger than the Subie turbo, that I know for sure.

 

I have had no issues with the glow plugs wearing down the battery, I have had an auto parts store sell me the wrong glow plugs and the ends of the glow plugs blew up like balloons, I was so lucky to get them out of the holes they were mounted in, I had to use vice grips to pry and twist them out, I was so lucky that day to get them out of the head, but the engine started the best it ever had that one time, but the glow plugs never worked again as they got burnt out the first use, Baxters was very unhappy when I btought them back.

 

 

Edited December 16, 2018 by wayno

[620slodat]

Diesels are different from gassers in that they need lots of air, and the motor RPM's are dictated by how much fuel is injected. Adding fuel WILL mean higher EGT's when there is no change in air available. More fuel NEEDS more available air to bring down EGT's. All this must be taken into consideration when adding a turbo. For this reason diesels will take more air both intake and exhaust without harm (even if more fuel is not added) which can possibly affect the efficiency of the motor in a positive way. More air flowing through, within reason, can make a real big difference in how the motor reacts. I know you know this, but I need you to know that I understand it before asking my next question. How much difference in size is there between the throttle bodies for the SD-22 and 25? Do you think the extra work of changing to an SD-25 intake is worth it, and if it can make any difference in power available? Or is it not worth the extra work when adding a turbo? Also, adding more fuel and air can decrease the fuel mileage. It's a two headed snake, more can mean less and less can mean more.

 

The first thing I did, before the first start, was replace the glow plugs that were in the motor just in case they were the quick glow type (which I later determined they probably were).  I learned from reading about the GM 6.2 and 6.5 NOT to use quick glow type as they will do like you had problems with. The quick glow plugs will work generally only one time in a normal/manual system, enlarging the tips enough that it will be difficult (or impossible) without removing the head. The quick glow plugs are for a special built low voltage system. For glow plugs I think I got Beck-Arnley 176-1034 for a 1981-1982 SD-22 (it's been two plus years since I got them and will have to look up what I got), which near as I could find are NOT the quick glow type. 

 

Since you rebuilt an SD-22 I'm assuming it was a three main bearing crank. According to what I found anything after motor serial number 618766 was a five main bearing crank and three ring piston. My motor has a serial number almost 98,000 after that, so I'm assuming it has a five main bearing crank and three rings on the pistons (never had the motor open yet). Also, from what I found all the SD-22 motors had piston oil squirters. Is this correct?

 

I have never tried getting any parts for the SD-22 yet, except the glow plugs, and they are close to spark plugs in availability.. I know you said that a Nissan dealer will have the best head gasket. Will the Nissan dealer also be the the only place to get good gaskets for the oil pan, intake/exhaust manifold, and valve cover? I should get them to have on hand, maybe even the front and rear main seals. I don't want to spend my hard earned money on inferior gaskets or parts.

 

I may need to move the battery to have room for peripherals (power steering and AC pump) on the motor. The original battery set up for the SD-22 only had one, but I was wondering if I needed a second for storage cushion. Moving the battery would present a good time to change to two batteries if needed.

 

 

[wayno]

OK, I understand what you are saying about air, but diesels do not operate at the rpms gas engines do, so they use less air, if you use a turbo made for a 2200cc gas engine, I believe you will have issues building boost as the gasser turbos kick in at 4000rpms and up on that gas engine, well your SD22 engine has a redline of 4000rpms and it sounds terrible when it goes up that high, I have had both an SD22 and SD25 up at 3500rpms, the SD22 going down hill, and the turbocharged SD25 going thru the gears for a guy/kid that has a 720 diesel himself, all he said to his dad after I took him back there where he was when I picked him up was "that thing is fast", normally I do not go over 3200rpms, I try to keep it 3000rpms or less, I shift at around 2500rpms, that is why I like 3.50 gears or better yet 3.30 gears in the rear, and I changed to them gears after turbocharging the vehicles, I did use 3.70 gears in my 720 with an SD22 engine, it struggled on the freeway.

All the threads I ever read that used a T25 or any other larger turbo were failures, all of them had issues with building boost, they got maybe 3psi and then we never heard from them again, I do not recall what turbocharger that drifter in Australia had, but he did have boost, but in the end he converted over to a VE type injection pump because he said either it was floored or it was not floored, there was no real in between.

I do not believe that you need the SD25 intake manifold/throttlebody thing with a turbocharger, the engine just does not move enough air at the lower RPMs(envolope of operation), I hardly even have my foot on the pedal anymore except on the freeway, at 75mph I have my foot 2/3rds into the pedal, and driving around town I might be into the pedal a 1/3rd of the way down, when I talk about this, I am talking about driving my 521 kingcab SD25 diesel with a stock inline injection pump and the 1800cc Subie turbocharger, the truck runs great, and if I could drive 55mph I would likely get around 40mpg or better.

My 720 SD25 turbocharged diesel is different, the guy that put that engine together had a few things modfied like I have mentioned before, the intake vane housing was machined out to take a larger vane, and he had the injection pump turned up to make it run richer, I think both these mods were a mistake, but I do not drive like that guy, he drove 50/55mph on the freeway, and he started out from a stop like a very old half blind man, I am sure it was very agravating having to follow that guy, the issue with the turbo is that it is spun up/building boost from almost an idle, by the time one gets to 2000rpms it is at 15+psi boost and I let off and press down on the pedal again and it goes right back up to 15psi boost, my 521 diesel only gets up to 15psi breifly when picking up speed to say get on the freeway, once I get up to speed and hold an even rpm the boost PSI goes down to 4/5/6psi, well the 720 just stays at 15psi all the time, that cannot be good on the engine, and it certainly can not be good on an old engine with miles on it, so I had to set that turbo at 7psi and it is bypassing all the time, having the wastegate open all the time cannot be good for it either, but I will say this, that truck has 3.30 gears in the rear, the pump is turned up, and the intake vane is larger and therefore it spins up quicker, that truck has a shitload of torque even at 7psi, and it has more power at 15psi, and it keeps picking up speed on the freeway at 20psi, this engine has a VW 1600cc turbocharger(modified) made for a car.

My 521 has plenty of power as far as I am concerned, it is about the same as it was starting out when it had no turbocharger, but from 3rd gear on up it has lots of power, and on the freeway it is a totally different truck than it was without a turbocharger, it is actually pleasent to drive and I get better mileage.

 

Yes my SD22 I rebuilt has 3 main bearings, this was before I ever had a turbocharged diesel engine, it also has a VE type injection pump, it has no more power than any of my other SD22 engines I had, I was going to put that VE type injection pump on my SD25 to turbocharge it but firgured it all out before that happened, but I was getting close.

As far as I know all SD series diesel engines have oil squirters.

I have had no issues with any diesel gaskets myself and I have bought them from baxters also(oil pan, intake/exhaust, valve cover, ect), but I have never replaced a headgasket except when I rebuilt that SD22 engine and it had the OEM metal type headgasket in the kit I bought, now that kid I mentioned before, his dad did do a headgasket, he bought it from Baxters, it looked like any generic gasser headgasket, it had no metal at all in it, it didn't even last him a week as I recall, he borrowed one of my OEM gaskets and he ordered me a new OEM gasket from the Nissan dealer and gave it to me when it arrived, that OEM gasket lasted till he sold the truck, he said the OEM headgasket was very expensive.

 

I had to cut a hole in my 521 inner fender to move the battery tray away from the engine in the engine compartment, I have not planned to lower my 521 much so it should not be an issue having the battery tray sheet metal that close to my passenger side front tire, if I lowered the truck 4 inches, having the wheel cranked all the way to one side or the other might be an issue.

 

I have never needed a second battery, I do not see the need, I have a 521 with an electrically powered hydraulic dump bed and that one should have a second battery but I only have one battery in that one also, I am a big fan of keeping it simple, two batteries is not as simple as one battery, plus I have no room in my 521 turbodiesel to fit another one in the engine compartment, I do not camp out anymore where I would need the extra battery to charge stuff or run an electric cooler, so I only have one battery in all my rigs now.

These engines are not like big diesel engines where the starter needs to have a shitload of power to turn it over, what surprised me was how easy these diesel engines turn over by hand, but if you try to pull the truck to start the engine it doesn't work as well, the rear wheels just skid as the engine does have a 22 to 1 compression ratio, it turns over slow easy, not so easy to turn it over fast like when pulling it down the road.

[620slodat]

You are correct in that diesels operate at a much lower RPM than gassers, and consequently use less air. What I am trying to say is that the quantity of air can be increased without increasing fuel quantity and diesel EGT's won't go up, but maybe down instead. Whereas with gassers when you increase the volume of air without increasing the fuel quantity the motor temperature will go up, and very likely valve burning incidence, and other negative stuff, will go up. But, increase the air quantity along with an increase in fuel, and the gasser won't significantly increase motor temperature.

 

Yes, I understand that the size of a turbo is important to a diesel motor. Too big a turbo and you will increase air at too low of an RPM for the amount of fuel injected, or too much total air, and a turbo will be a waste of effort. I haven't figured out yet what turbo I will use. That will be later, just that it will have to be sized properly for a small diesel motor.

 

I do have the stock turbo off my Chevy pickup. I replaced the stock turbo with a Holset HX35W from a Dodge Cummins. The stock GM turbo supposedly runs out of breath somewhere around 3000 RPM, or less, and the HX35W won't. But, most likely the stock GM turbo will be way too big for the SD-22.

 

I need to get extra gaskets to have on hand, and knowing that local parts store gaskets are probably OK (except for head gaskets) is good for me to know. I just don't want to spend good money on poor quality gaskets. Before I finalize the swap I should remove the pan to see how many mains it has so I know what I may deal with when I turbo the motor. Do you have any words of wisdom about the pan gasket? Glue it to the pan, but not to the block? Don't use any gasket sealer on either side of the gasket? Cork or rubber gasket?

 

Your battery experience is good to know. I haven't looked at the battery situation yet, but I am planning ahead for amps needed, and anticipating needing to move it.

 

Your experience with starting the SD-22 or 25 without using the starter is interesting to me. Makes me wonder if using fifth and a very low speed would be any good.

[wayno]

I do not believe you are getting what I am saying about the turbo size, if it is too big it will not spin up the turbo at all, at least not fast enough to build any boost, the exhaust air just goes thru the vane fins instead of forcing it to spin faster and faster.

If the turbo is small the exhaust exhaust air is forced thru the smaller exhaust hole much faster and that makes the exhaust vane spin faster therefore making the intake vane spin faster building a lot of boost, and the exhaust air is FORCED thru that smaller hole/vane.

A larger turbo the exhaust air is not forced thru, most the exhaust air goes thru the vanes at an idle, and when one opens the throttle up it struggles to get that exhaust vane spinning, now if it struggles to get that vane spinning, the more PSI on the intake/commpressor side that is built, the harder it is to turn the exhaust vane, the more the exhaust air goes thru the vanes instead of spinning it, I believe that is why a lot of them threads I have read had unhappy endings, they could not build any significant boost because the turbo was too big and would not build any significant PSI/boost.

On my 720 turbodiesel with the modified/larger intake vane I had enough boost when it was setup as a draw thru, but set up that way it ran lean, I ran into a wall at around 60/63mph because it was not getting enough fuel and the EGTs were as high as they were going to get(not very high), after talking to that guy I figured out how to make it richer by adding a valve and there was no more wall, I almost did a 100mph on that first test drive, but draw thru systems have other more critical issues with these inline injection pumps and the turbo types I have/use, but blow thru systems on these engines/injection pumps/turbos I use have way less issues, as a draw thru I could never let anyone else drive the vehicle, while as a blow thru I can let others drive it, but I talked about the turbo vacuum issue stuff in my threads and what I did to try and minimize the issue. 

 

Too big of a turbo will not increase air flow in my opinion, but it will not decrease air flow either, I suspect it will drive like there is no turbo at all, in this situation bigger is not better.

 

It sounds like you might have one of the rare 5 main SD22 engines, I have never seen one before, I wonder what type of pistons it has, I wonder if it has turbo pistons.

 

I use sealer on all sides of gaskets on the oilpan, that is something I do not want leaking as it is a pain to change it out with the engine in the truck, also it is very awkward laying on ones back under the truck dealing with it, I do not recall what type of gaskets I have used on my diesel engines, the SD22 I rebuilt has a cork one as I just now looked at it, it also appears to be leaking, it likely has under 500 miles on it.

The pulling the 720 diesel truck to start it is not my experience, someone on here talked about pulling the truck to start it and I suggested that the rear wheels just skidded down the road and that is what happened, but in the end I believe they were able to get it started in second gear dragging it down the road.

 

[620slodat]

 

After looking back and re-reading what I wrote I should have clarified what I was talking about. I think we are talking about two different subjects. I'm talking about the intake up to the head and the exhaust after the turbo, and you are talking about the turbo itself. Both are very important to a properly running diesel. I understand that properly sizing a turbo for a diesel motor is very important to what a certain size motor can put out, and that too big a turbo for the motor size can be a problem to the way a diesel can run.  Also, a larger intake and exhaust is important as you have to supply the motor with plenty of air for the fuel injected, and you have to quickly remove the spent fuel after the turbo has done it's thing (to allow the turbo unimpeded flow of exhaust gasses).

 

Right now the motor will need to be pulled again as I don't have the flywheel or clutch in place. When I pull the motor to put the flywheel and clutch in I'll have to pull the pan so I can see how many mains it has. In the SD-22 you rebuilt do you remember what the bottom side of the pistons looked like? I can send you a picture of them when I pull the motor. I should also be able to see if it has squirters.

 

We are looking at the gasket sealing situation from two different aspects. You are wanting to make sure the gasket never leaks after the sealer dries. And I'm looking at things as if I may need to remove things later and will want to re-use the gasket. I can understand where you are coming from as I also don't like leaks. I will need to consider where the item is (like the pan) and how much is involved with cleaning the gasket surface on the block.

 

 

[wayno]

If you look at the photo of the adapter I made to mount the turbo to the exhaust manifold in a post earlier in this thread you see that the hole is not that large, that hole is not even close to the intake hole in my throttle body/carb looking thing on my intake manifold and my engine runs great.

Another thing to note, when I finally got around to looking at that home made exhaust manifold that sat around for years on a shelf because I never thought it would work properly, well when I removed that adapter it had on it for that larger turbo it had on it and seen that giant hole I thought, "that might work", the reason for tearing it apart was to scrap it, as I have a lot of stuff around here, well I changed my mind right then and there, I thought give it a shot.

Keep in mind that the way that exhaust manifold was made with the hole cut in the side and the stock exhaust exit location welded up I thought there was no way the exhaust flow was going to flow efficiently moving backwards in 75 percent of that exhaust manifold, but it made it a lot easier to pipe the turbo exhaust out thru the stock exhaust exit area, I actually planned to make a "U" pipe to mount my turbo like it is mounted in the 720, but when I seen that giant hole in that home made exhaust manifold I changed my mind.

My thinking comes back to the same thing every time, diesel engines do not move air like gas engines do, they operate at much lower RPMs and move less air.

I believe when I bought my first SD25 out of the side of that guys yard(sitting against the side of the house in mud) that it had a SD22 intake manifold on it as it used the SD22 intake piping/sheet metal piping, I always wondered if it had an SD22 injection pump also, it ran fine that way for years, but when I put the turbo on it I took the intake manifold off another SD25 I had(was over heated) and put it on the engine in my 521 truck, if I were to guess right now with all the stuff I have done of the years I would say that what you have on your SD22 intake manifold will work fine, I suppose if you were racing it or doing burnout contests like them guys do in Australia a larger intake manifold might make a slight difference, but for normal driving I think what you have will be fine.

 

My 521 has a two and a half inch exhaust pipe from the turbo back with no muffler, the pipe goes all the way to the rear of the truck.

My 720 has a 3 inch pipe from the turbo back with no muffler, it exits to the side at the ground just in front of rear wheels.

 

OK, my intakes are weird, even though the turbos are different sizes, both have around one and a half inch pipes coming off the turbos, but the 521 has no adapter, the tubing is mounted directly onto the DSD25 throttle body/carb looking thing, my 720 has an adapter on top of the throttle body/carb looking thing, that adapter allows me to use the SD22 intake piping from there to the airfilter canister, that adapter has the same size hole as an SD22 throttle body/carb looking thing hole, so basically I have an SD22 intake on my SD25 powered 720, now I never really gave that much thought till now, I have no idea if that plays any part in why my 720 doesn't really drive well on the freeway, I can drive nearly 100mph but my foot is buried in the pedal, but I believe that the modified intake vane on the turbo is the biggest issue at the RPMs I drive on the freeway, I have too much boost!

I have another turbocharger I can use, but I would have to make a new head pipe and since I hardly ever drive that truck I do not see the point right now.

 

The piston squirters/oil jets are connected to the block and are pointed up at the back side of the pistons, as far as I know all the SD series diesel engines have them, in the photo below you can barely see the oil jets in this 3 main bearing engine.

[Charlie69]

On 12/6/2018 at 8:04 PM, 620slodat said:

I still have a ways to complete the project, and as time goes on and reading continues I seem to add to what I want to do. What I would like to do is: change king pins to ball joints, change to disc brakes in the front (still thinking/reading about rear discs), change one piece steering column to collapsing column, add AC, maybe increase alternator amp output (different alternator which would require changing vacuum source, and maybe other changes). I have more possible changes, but they require more money, so they most likely will go on the back burner.

You can do all of the above with a 720 chassis swap. Find a diesel 720 truck cheap and you have everything you need already there in the 720.  Set you bed and cab on it and run the electrical, plumb the brakes, connect e brake, and plumb the clutch master. and you have all that you are asking for and also a ball joint rear end, outboard idler and pitman arms.

[620slodat]

Wayne, I'm glad you brought up exhaust pipe size as that is something I have been questioning. What diameter of exhaust pipe do I want? I'm old school in that I don't want real loud, but I do want a real free flowing exhaust. I have about two feet of the stock SD-22 exhaust, which is about 1 5/8 inch outside and close to 1 1/2 inch inside diameter. You have both 2 1/2 and 3 inch exhausts and there is a real big difference in volume from stock to what you have. What is your preference for size? I realize that both are on motors with turbo's which need larger exhausts. I'm going to need to install a complete new system and I want to size the exhaust for a turbo. I don't want to install one for an NA motor, and then turn around and install a new system for a turbo when I add a turbo later.

 

I realize that you have one system that goes clear to the back of your pickup, and another that exits in front of the rear wheel, and that both are without mufflers because of turbo's (NA will need a muffler). This will make a difference in sound, and to complicate things more each system is a different size. But, which sounds better to you, and why.

 

Thank you for posting that picture of the inside of the crankcase. Now I don't have to question what to look for when I look for oil squirters. But, that does also bring a question to mind. Is their any difference in length of blocks between three main bearing motors and five main bearing motors. It seems to me that the crank would need to be a little longer with five mains.

 

Charlie69 brought up an idea that I haven't really played with. Since you have experience with swapping frames, will a D21 frame easily swap over in place of the 620 frame? I looked on Craigslist this morning and found a 1990 D21 that was rolled and appears to have a straight frame. All the frame swaps I've read about involved putting a 521 cab onto a 720 frame. If this is possible it would involve putting a 620 cab onto a D21 frame. I'm thinking that if it is easily possible that it would have been done already. This makes me think that it would be more difficult than putting a 521 cab onto a 720 frame. IF-- it is not too difficult I would end up with ball joints and disc brakes without any difficulty AFTER the cab swap. But, I haven't read of this swap.

[wayno]

The SD22 and SD25 are basically the same size engine, so to answer your question, if the block/crank size was different they likely would have called it something else, the 5 main SD22 is likely just a small version of the SD25, I have had both in the same truck and there was no difference, by the way I have an SD22 valve cover on my SD25 in my 521 diesel kingcab.

 

The exhaust size was more determined by what I had and what room was available to route the exhaust out after leaving the turbo, the 720 engine that came out of the Volvo had 3 inch exhaust when I bought it, there was just enough room to get that exhaust pipe thru/past the "U" pipe coming out of the stock exhaust manifold, the alternator, starter, block vent, frame, and torsion bars amoung all the oil lines, ebrake cables, vacuum pump and assosiated lines for the power brakes and other such stuff in the way, the 720 has way more room than my 521, the reason the 720 exhaust dumps to the side/down in front of the rear wheels is because that is all I could do with what I had, there was no way I was going to get it over the rear axle myself, so I settled.

The 521 has the 2 1/2" pipe for a reason, that was the size of the hole the subie turbo flange had, so I used that size all the way back, it just fit thru the torsion bar/transmission case area, I had to make a few bends to get it thru, the exhaust shop made the rest from that point to the rear, there was no way I could route it like the 720 because the 521 turbo was mounted lower(does not stick out the hood) and farther back, there is no room for anything else in the 521 engine compartment, to get the starter out if it goes bad I will likely have to remove everything turbo related.

 

I do not know what either engine sounds like as I am driving it, but the farther away the exit is from you the quieter it will likely be, I do not really drive the 720 anymore, the 521 is much nicer to drive.

 

OK, the chassis swaps are determined by the laws in your state, when I did my first two swaps Washington state didn't give a shit about frames, I could get rid of a 521 frame without needing a title, things have changed now, I need a title to get rid of a fender, hood, door, frame, trunk lid, my chassis swaps are over with in this state, as to get rid of auto parts without giving up the title you have to cut it up so small they cannot tell it ever was a vehicle.

I have done 6/7 chassis swaps, I had titles for both the frame/chassis and the cabs for five of them(2 titles, one vehicle), the other 2 would be hard to sell out of state if I were to want to sell them which I do not want to do, the laws have changed over the last 10 years.

Legally I need to take the vehicles in to have the VIN numbers verified, then go to the DMV and have the titles combined.

 

There is a thread here on Ratsun about putting a 521 cab onto a D21 frame, here is the link below, maybe that thread can answer some of your questions, I believe he also lives in Oregon, the 521 and early 620 are almost the same with a few differences chassis wise, I believe the transmission mount is different then the 521.

https://ratsun.net/topic/69946-521-on-d21-frame/

Too bad I don't have a title for the extra 720 kingcab diesel frame I have, I would give it to you just to get rid of it, it came from the McMinnville OR area.

Edited December 20, 2018 by wayno

[620slodat]

Well, we will see how the five main block is done when I get to the point of pulling the pan. Until then I will just have to wonder.

 

I just wasn't thinking I guess. You are right about the turbo exhaust outlet dictating the size of the exhaust pipe. I have either three or three and a half inch (memory isn't working) coming out of the turbo on my Chevy 6.5, with it changing to four inch under the front of the passenger floor. I can live with the sound until I am picking up speed with a load on, and it is my workhorse/firewood hauler. 

 

I'm going to have to go to DMV and ask questions about doing a legal frame swap, and soon too as I want to know if it is worth the hassle before the D21 on Craigslist is gone. I searched and found that same thread that you put in the link for. I read all ten pages today, and what I got out of them was that it can be done, but may not be easy. At minimum parting it out may be worth the few, or many, parts I can get out of it and selling the rest.

 

Depending on what I find out when contacting DMV I may take you up on that 720 frame.

[wayno]

Keep im mind that I have only dealt with 720 frames/chassis, I know that the 521 cab will fit on one and not have the stock 521/620 wheels/rims sticking out past the fenders, as the years have went by the trucks/chassis have been getting wider and wider, my 1966 Datsun 520 is sitting on a 1986 720 frame, it is lowered 6/7 inches in the back and around 6 inches in the front, the 620 disc brake wheels/rims barely clear the sheet metal in the rear, and the front was also an issue even after I norrowed the front stance, so I made another set of front lower control arms and narrowed them even more(both sets are drop arms), but with the right tires(185/60R14) I believe I may be able to put the first set I made back on the truck which were only narrowed maybe a half inch, while the second set I made were narrowed 1 1/2 inches on each side.

The point is I do not know or at least remember if that guy that put the 521 onto the D21 chassis/frame had any issues with stance/tires sticking out past the dender wells too far, my 521 kingcab with the stepside box was not lowered and I actually had the oppisite issue, the rear wheels were too far inside the fenders, the 1986 rear axle helped a little, and I would go with wider rims but then the wheels stick out the front too far, so I am living with the rears tucked in a little farther than I like.

 

I would go with the exhaust going all the way out to the rear bumper rather than having it dump out the side, it's not particularly quiet when standing in back of it, but it is fairly quiet in the cab even with the windows rolled down, I do not really drive the 720 enough to give you a recomendation dumping it out the side, but I have towed and driven it enough to know it was not that loud.

Here is how I did mine straight out the back, but after having it this way for a while I think I would rather have it pointed out the back drivers side where I can see the exhaust when I want to, this way it is I cannot see the exhaust color and the backend/tailgate gets black soot on it.

If you need the chassis/frame number PM me.

I believe you are using a different name on the Nissan diesel forums, you asked about the turbo exhaust manifolds on that forum, well a freind and I got ripped off of 4 exhaust manifolds and an intake by the guy that was supposed to make them for us, I still want to make one for my 720 and have considered trying to do it myself, but have been doing other things, I am not sure what I am going to do with the 720 anymore, if I got all my other projects done I would consider using that stretched chassis/frame as the base for a 4 door 521, but that seems like a long ways off right now.

 

I have thought for a long time that maybe the R16 and SD22(3 main bearings) might use the same crank design, the H20 is one of the reasons as it appears to be a stroked R16(diesel crank?), I always wondered if a higher revving diesel could be made using that R16 crank, just one I of the things I have wondered about over the years as the SD series and R16/U20 share the same front transmission case/starter location.

[620slodat]

After reading that thread yesterday my memory is somewhat fresh, and I don't remember anything being said about wheelbase width problems. He did have a problem with the 521 cab setting higher on the D21 frame than he liked though. From the pictures he posted the cab and bed looked good on the D21 frame. 

 

That brings to mind a problem I'm having with the older threads that I'm reading. There are pictures that show up as only a set of numbers, and so far I haven't been able to get any of them to work for me, while the actual links work for me. Is it my computer, or is there a way to be able to see them that I'm not aware of?

 

On a Toyota Landcruiser web site that I frequent it was well known that any exhaust that went straight out the back would have the exhaust fumes sucked inside the Cruiser, but if the exhaust was sent out the side behind the rear wheel the problem would go away. So, consequently, my plans were to send the exhaust out behind the rear wheel and not straight out the back, just incase somebody was to ride in the canopy.

 

Yes, I am using a different name on the diesel forum.

 

I called the local DMV today and talked to Nathan. Since I didn't have any specifics, VIN numbers, etc, he could only say that it was possible to swap frames and have it legal. First, the VIN numbers of both vehicles need to be checked by State Police for any problems, stolen, etc. The VIN number that they chose to use for the new title would most likely be the frame number, but the body number could be used if the frame number isn't found. So, I will most likely use the 720 frame. I"m assuming that it is a bare frame and will need both front and rear suspension and anything else that was bolted on also. One thing that I"m wondering about is if a 720 4 X 4 front suspension will work on the frame in a 2 X 4 set up since a couple months ago I knew where two were in a wrecking yard in Albany.

 

I looked up at the top of the page and didn't see anything I recognized for doing a PM. What do i need to look for, or do, to do a PM?

[wayno]

I guess this is the image I remember/got stuck in my head, but he was using GM wheels.

 

And this below is what he said when using the D21 rims, I do not know the offset of D21 rims and if they are the same or different than the 620 disc brake rims I use, I also use 320/520/521 rims but they need a little grinding on rivets or pounding with a hammer to clear disc brake calipers

 

 

Put the 14's that came w the nissan back on and stretched the bed around them. Dont know how much, ill find out when i center and square it. The bed was pretty beat to begin with so its not bending evenly. A little finess, a tape measure and some brute force/ignorance should get it close enouph. Plan on getting a better bed and using this for trailer skins

I do not know if the tires were the issue and why he had to stretch the sides of the bed to clear the tires/wheels, or if the rear axle is just too wide for his 521 cab/bed, I also do not know if your 620 axle will bolt onto the D21 chassis/frame, I do know that the early 720 axles are narrower than the late 720 axles, and I know that the chassis/frame I have is either an 81 or 82 diesel chassis/frame.

PM means personal message, if you put your curser on my username it will give you the option to send a message, I will message you after posting this reply.

I cannot see any of the later photos either, I only went back far enough to find these photos.

Edited December 22, 2018 by wayno

[datzenmike]

3 hours ago, 620slodat said:

So, I will most likely use the 720 frame. I"m assuming that it is a bare frame and will need both front and rear suspension and anything else that was bolted on also. One thing that I"m wondering about is if a 720 4 X 4 front suspension will work on the frame in a 2 X 4 set up since a couple months ago I knew where two were in a wrecking yard in Albany.

 

I looked up at the top of the page and didn't see anything I recognized for doing a PM. What do i need to look for, or do, to do a PM?

 

The 720 is going to be wider than the 521. The wheels will stick out. A D21 Hardbody even wider.

 

The body attachment points on the frames are different between 2 and  4wd 720s and your body will sit 4" higher than a 2wd frame. If using a 4x4 frame you can remove the front differential, drive shaft and CV joints. I guess you could take the primary driveshaft out, the transfer case and rear driveshaft and replace with one single long one piece driveshaft. 

 

 

Click on wayno and it takes you to his profile page. Near the center is MESSAGE. Fill out completely hit SEND at the bottom.

[wayno]

What you said is not entirely true Mike, my lowered 1966 Datsun 520 is on a 1986 Nissan 720 frame with the axle it came with, I am using 620 disc brake rims and 185/60R14 tires, when I installed the tires it rubbed on one side, I had to center the axle perfect to stop it from rubbing on either side, it only has an 1/8th inch clearance, but the rear tires do not rub even going around a corner, the chassis has been notched, 720 4wd leafs, 2" drop blocks, front leaf mount is 520 as the 720 mount stuck down too far, the rear shackle mounts are off a early(66-70) Datsun roadster, the carrier cross member was replaced with a flat piece that did not hang down, the front is even more dramatic, this truck is dropped at least 6 inches on all 4 corners.

If I can put a 520 cab onto that modified 1986 Nissan 720 frame/chassis without having to even change out the axle to an earlier narrower axle like the 81/82 axle, his 620 cab will fit on any 720 Chassis/frame without width issues, now rims can be an issue, I use Datsun 620 disc brake rims on all my rigs if I have them, otherwise I use 520/521/early 620 rims.

Now legally one has to do things a certain way, he has already started looking into that process, we shall see where this goes.

 

This is my 520 which you likely seen at Canby the year I drove it there.

Edited December 22, 2018 by wayno

[620slodat]

Datzenmike and wayno, thank you for educating me on how to do a PM on this forum. Starting a PM is really different on this forum than the Toyota forums I have frequented in the past.

 

Wayno, I sent a PM reply to you earlier this morning. 

 

Datzenmike, I realize the 720 is wider. However, what I am working with is a 1973 620 pickup. I don't know how much difference in width there is, but I know that an early 620 like I have has a narrower rear axle than the later 620. I don't remember any difference if any, but isn't the late 620 about the same as an early 720? No diesel 4 X 4's were imported into the states so it stands to reason that the frame that wayno has is a 2 X 4. Since the frame that wayno has is a Kingcab I don't know yet what I will do to take up that extra frame length. Maybe add to the 620 cab to make it a stretched cab, or add to the bed to make it longer, or do a little of both.

 

Knowing what some of the differences are between the 2 X 4 and 4 X 4 720 frames is helpful to me. Are there any differences in any of the suspension parts, especially the front suspension? I do know that there is a difference between the rear springs, but don't know of any others. If there isn't then I can use some of the suspension parts off the two 720's in the wrecking yard.

[datzenmike]

Later disc brake 620 front axle are very slightly wider than the early 620. Like an inch so 1/2" a side not noticeable on a truck. Rears are all the same

 

Early 720 2 and 4 wd are slightly wider than the late 620s, again about an inch more. Rears remained the same as 620s

'83 and on 2 and 4 wd are wider again front and rear.

 

Early 720 steering components was the same for 2 and 4 wd except the steering knuckles. '83 and on were different.

 

 

4X4 torsion bars and their locations are different. Lower control arms and sway bar totally different, hubs, spindles, brakes, steering knuckles. The 4x4 front end had a differential, drive shaft and CVs so everything is different there.

[wayno]

I did not get a PM from you so you did not do it correctly, did you see/find/receive the PM I sent you?

 

Like I said in my last post, I put a 1966 Datsun 520 on a 1986 frame without issues, so your early 620 will likely drop right on, now if it drops right on like the 520/521 does is a different story, the 521 front cab core support under the radiator is in exactly the same place as it is in the 521 chassis/frame and it centers the front wheels in the fender wells perfectly, but this does have one issue, it puts the head/block right next to the firewall(doesn't touch), the issue is the heater core hoses, now what I did was remove the heater box and then I cut both heater core inlets/outlets off just inside the firewall, I then installed a couple short hoses with 90 degree bends that put the hose against the firewall after they come thru and they ended up where the 720 diesel hoses are after they came thru the firewall, I then connected the stock diesel hoses up to them hoses like you can see in the photo below.

Making a kingcab is not easy, the easiest thing to do would be to make a flatbed, second would be to lengthen your 620 bed, well that is not true, it would likely be easier to put a stepside bed on it and adjust the fenders to center on the rear wheels, shortening the chassis/frame would also be an option, but other issues arise although they can likely be dealt with easier than when one lengthens the chassis/frame which I have also done.

Dmike has put a 620 cab onto a 720 4wd frame in the past, but I do not know if it ever seen/was driven on the road.

 

My email address is below 620slodat, just email me instead of using the message system here.

 

tmdatsuns@gmail.com

[wayno]

By the way, I like the later rear axles because they have auto brake shoe adjusters on them.

[datzenmike]

They do! From November '82 on same as when the Z24 engine was introduced early in the '83 model year.

[620slodat]

Wayno, put together an e-mail last night, but found it still on the computer this morning, not sent. I guess I got busy last night and forgot to send it. I did send it this morning though.

[wayno]

Message was received and one was sent.