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Introduction for 620slodat and his diesel build


620slodat

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I've been lurking and reading a lot for several months now, so I finally signed up. I have my Dad's 1973 620 that he bought new, manufactured in 7/73. After he passed away I talked Mom into keeping it and having it available for my brothers to use when they needed it. That worked for several years, then something happened to the motor.  It had over 200K on the motor and I was never interested in trying to find out what happened. To me it acted like it jumped time (spendy?), so it sat for several years. 

 

About 3 years ago I found a 1981 SD-22 (diesel), with transmission and radiator. If I read the very faint markings from the wrecking yard the motor has just over 80K miles on it. My plan was to put this SD-22 into the 1973 620. I have had the motor running,  with good oil pressure, while setting on the floor, so I am very slowly moving ahead with the project. I am on a limited income so it has taken me this long to get the motor and transmission temporarily set in place. Summer time I get very little done as I spend most of my time in the garden and on the property, so most of my available time is in the winter. 

 

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. 

 

What I need now is to make contact with Beebani since he lives so close to me. I have watched a bunch of Mike Klotz's (blue hands) videos. I would like to send out a great big thank you to him for the videos as they have helped me out considerably. Well, back to perusing the old threads.

Edited by 620slodat
preparing for merging this thread with the thread in the 720 forum
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Thank you wayno for chiming in. I was hoping for your input. I did meet you at Canby in 2017, and you drove your extra cab pickup there.  

 

Yes, I'm aware of the low HP that the SD-22 has, and also aware that it can be difficult to turbo, although you are the first one I have read about that has successfully turboed them. I do have your explanation printed off about how you did it. Just as a side note, I do have 2 notebooks full of stuff that I printed off over the last three years about the SD-22 and the 620.

 

Because of what I have found online I have been able to understand the IP and get the motor started.I don't have the wire loom and portion of the operating circuit that is in it, although I do have the injection pump controller (looks like a wiper motor). I found an ignition switch that I hope will work. From the off position it has one spring loaded position to the left, which I plan to use for shutting the IP off. To the right of the off position is the run position, and the spring loaded start position. I'm not sure about the over-inject yet (equivalent to a choke in a gasser), but I'm hoping that I can get the over-inject to work with the start position in conjunction with the starter. The glow plugs are going to be hooked up to a relay and a spring loaded switch, like a starter button switch.

 

There is a lot more that I have found/learned about the SD-22, but it is very late for me (early to bed and early to rise) and I need to get to bed.

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I forgot about this thread, I have extra wiring harnesses for sale if you are interested in having it work the way it is supposed to when it came from the factory, PM me about that.

I myself use them in all my builds, I guess I understand them and how to modify them for use in my 521 builds, my last build(the work truck conversion) I even figured out the dash lights so they come on with the switch as intended and they are dimmable also, but I have never done a 620 instrument cluster either, they may be different/easier.

The SD25 diesel engine I have in my 521 kingcab came out of a 620 pickup, I never seen it in that pickup but two crate engines were bought, one went in that 620 and the other went into a 521, the 620 truck rusted away and was scrapped by his family after the owner died, the 521 was crushed when the pole building it was in collapsed from snow buildup on the roof, I was told it was being rebuilt and I have no idea if that diesel engine was turbocharged like mine was even though I believe it was a failure as the boost release/bypass was wired shut, it had a rather large turbocharger, but I never tried to make it work, I went with the mid 90s 1800cc Subie turbocharger I picked up years before, the only thing I can say is I wish I had done the turbocharger thing years before, I would never daily drive one without one now, it would drive me crazy.

There was this guy on the Nissan Diesel forums called Knucklehead I believe that had the "turbo the bomb" thread as I recall, he actually is the first one to succeed in turbocharging an SD22 engine as far as I know(his thread does not have a happy ending), when I talked to him on the phone his explanation was way too complicated for me with a couple expensive devices, but he said something that gave me an idea about how to get more power out of my draw thru setup as 65mph was about it for that way but it got up to 65mph fast, I put in a valve with a line coming from a boost source, I piped that line from the other side of the valve to the vacuum line going from the venturi to to the injection pump, what this did was move the injection pump in a controlled way to a richer position, I took the truck for a drive after making my modification and I likely did a 100mph, I do not know/remember how I made the jump from this semi successful draw thru setup with a vacuum issue to a completely successful blow thru setup like I have now, but that conversation with that guy made me think about the subject in a different way.

 

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I wish I could afford the wire harness out of a diesel pickup, but we are currently paying off several thousand dollars in medical bills which puts us on a tight budget. Maybe in the future I will be able to afford it, but for now every dollar I put into the swap comes from what little I can earn on the side. It would be nice to finish this swap right away because of the potential for fuel savings over what I pay out now for gas, but I'm going to have to be content with putting only a few dollars at a time into it. Fortunately my time is free, and I have lots of it during the winter. This gives me lots of research time.

 

So wayno, you are not the first to turbo an SD-22/25, I was thinking you were. Anyway, yours is the first successful attempt at turbocharging over a long period of time that I have read about. I am on Nissan Diesel under another screen name, so I have been able to gather information from that site also. Lots of good information there, but that site is very slow moving.

 

I recently came across information about the Nissan S15 6 speed transmission (FS6R92A). The gear ratios look like they would come close to fitting the diesel motor, maybe with a few less RPM between gear changes. If I've found the right information the ratios for the diesel transmission are:  1st/3.592,  2nd/2.057,  3rd/1.36,  4th/1.0,  and 5th/0.821. The ratios for the 6 speed are:  1st/3.626,  2nd/2.20,  3rd/1.541,  4th/1.213,  5th/1.0.  and 6th/0.767. Just looking at them 3rd and 4th in the 6 speed are close, but could be good for in town. 4th and 5th in the 6 speed could be good for local roads. 6th in the 6 speed might be a bit high, but then might work good for the freeway once the SD-22 is turboed. I don't know if it can be made to fit the SD-22 since the starter is on the opposite side of the bellhousing, and I don't know if the bellhousing can be changed to one that will fit both the back of the motor and the front of the transmission case, but at least I can dream. Do you, or anybody else for that matter, know anything about this transmission. I don't know how I can afford this considering our financial situation, but dreams start out real cheap.

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Your better off finding a set of 3.50 gears out of a 1986-93 hardbody with a H190 rear axle, if you turbocharge the engine it will likely have the torque and HP to turn them gears, if you do not turbocharge the engine use the 3.89 gears the diesel trucks came with, it will be just fine when driven under 60mph except on the freeway hills, these engines just do not have the HP to keep them moving up the hills unless turbocharged.

All my diesel drivers are turbocharged, I am turning 3.50 gears in my 521 kingcab, and I am turning 3.30 gears in my 1980 Datsun 720, with the turbocharger they have the torque to get the trucks moving, I have actually towed another diesel 720 behind my 720 diesel truck without issues, but it is not just let the clutch out with 3.30 gears to get it going, I have to let the clutch out slowly, my 720 diesel has a shitload of torque as the injection pump has been turned up and the turbocharger has been modified to spin up at lower RPMs, but it doesn't like the freeway as it has too much boost all the time because the turbocharger was modified, I like my 521 turbodiesel a lot, it has good torque, but it also likes the freeway and goes 75mph with just over 5psi boost except on the hills where it can get up to 7/8psi, keep in mind that I have SD25 engines in my trucks, they are rated at 71hp to start with where the SD22 is rated at 61hp, like I said that knucklehead guy on the Nissan Diesel Forums turbocharged SD22 engines, the only reason I talked with him was because he was selling his fresh rebuilt engine on craigslist so I sent him a message and then called him, that is how I found out who he was, I suggested he update his "This is the Bomb with turbo" thread, but he didn't update it, I am so happy I talked to him though, as I would likely never have thought about doing what I did if I had not talked to him.

I would sell a diesel harness for fairly cheap as I have a few extras, PM me if your interested, most of the harnesses have every single component on them except for horns, lights, exterior stuff like that is not diesel specific.

 

The only 6 speed I have seen was huge and I didn't look at it that close, it would take a fabricator to even try to mate it to a diesel engine, almost anything is possible if you throw enough time and money at it.

Edited by wayno
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I don't have any machining experience, or know anybody with machining equipment (I'm a retired custom cabinetmaker so I'm used to quality and working down into less than a 64th of an inch). Anything that requires machining is automatically something I have to really need in order for me to pay somebody else to do the machining. A 6 speed for me is not practical if I can't use wrenches and other parts to make it fit my motor. I will just have to dream I guess. Also, I don't want to do any more body work than is really needed.

 

The first hand experience with rear end ratios is real good information for me. The current ratio in the 620 is 4.375, and I was considering using that and 15 inch (or larger) rims, as I want larger front disc brakes in the future. I will have to modify the rear brakes at the same time, but the jury is still out on disc or drum brakes. I do have extra 15 inch rims for my Toyota FJ40, so I can experiment with size.

 

Currently saving up for and spending money on a turbo is more important to me than wiring. I can get the motor running using my current knowledge about the system, and using the ignition switch I have. I will keep the diesel wire harness in mind for later though.

 

Something I just thought of, I need a bottom tank for a stock 1981 720 diesel radiator in order to get the 620 diesel running. My stock 1981 radiator is good and holds coolant, but I need to move the top hose over to the right about 2 inches, and remove the filler cap and use a remote filler. The filler cap can be removed and just have the location filled in, but I don't think the tank is big enough, or built properly, to allow the hose to be moved. I haven't checked with a radiator shop yet to see what they would say, or a new tank would cost, since Albany no longer has a radiator shop. It would require me to go clear to Salem (20+ miles), or beyond, to find a shop. Sweet Home has a business that builds radiators, but it is 40 miles one way, and I would have to go up there and back twice to get my radiator changed.

 

At Canby I saw a 620 that had a stock Nissan diesel motor and radiator put in it, but they had cut away part of the top plate of the core support to do that, and it looked UGLY (I want a stock look). My radiator will fit in there under the top core support with the filler cap removed. And with the top hose moved over a stock electric fan (which I have) from about a 2000 Nissan Sentra will fit that radiator without doing any modification to the fan frame.

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OK, 4.37 gears are not going to work for a 2wd diesel truck, you will be almost floored to do 55mph, you will have lots of grunt/torque power to pull stumps out of the ground but it will be worthless on the freeway, now if it was a 4wd will 33 inch tires it might work. you need 3.89 gears without a turbocharger, with a turbocharger you will likely be good with 3.5 gears with an SD22, keep in mind that my experience is with SD25 engines, I have never driven/rode in any SD22 powered truck with a turbocharger, I do not know how much less power it will have than an SD25.

I am using a modified Datsun 521 L16 two core radiator in my 521 kingcab diesel powered truck, I had the outlets moved to the opposite sides, that still created radiator hose clearance issues, so what I did was take the 720 diesel fan off the water pump and I made a jig that held the fan blade, I cannot remember how I did it, maybe I used an old water pump off an engine I parted out, anyway I mounted it on my band saw table and cut off each fan blade very slowly while spinning the blade threw the band saw blade, I cut off just enough to clear the lower radiator hose, now I had no issues at all with the truck overheating for the next 6 years except when going up a freeway pass hill, being floored or almost floored for that long the engine got hot, it took a while but it got HOT, since putting the turbocharger on my 521 kingcab I have had issues when it is hot outside, it get a little warmer than I like when above 85 degrees outside.

By the way, they make radiator fillers that fit in the upper radiator hose, I have seen this before but never looked into where to get them.

The 720 diesel radiator will not even fit in my 521, it is too wide, I am thinking about going to the wrecking yards and finding a 3 core radiator out of something and trying that on my truck as I do not want to hurt my engine, it runs so good right now.

Radiators are expensive to have made/rebuilt, if your 720 diesel radiator will fit in the 620 change the stuff around it like I did and make it work.

I paid $50.00 for that Subie turbocharger I have in my 521 kingcab at a wrecking yard, as I recall it was for a 1800cc gas engine, mine is a 2500cc engine, my other SD25 turbodiesel has a 1600cc gas turbocharger out of a BMW I believe, I think that is what you should use with the smaller SD22 engine, but I am just guessing like I was guessing when I bought that Subie turbocharger, it was a great guess, you should not have to save up too much, you just need to find a good used one somewhere, check for play in the shaft and make sure all the fins are good, you will need to spend your money on the hoses and custom exhaust unless you can weld and make your own, I made my down pipe from the turbo to past the torsion bar on that side, I paid a shop to do the rest, I have no muffler, it's a straight 2 1/2 inch pipe all the way to the back of the truck, I made the 720 exhaust from the turbo back to just in front of the back wheels, but I had new pipe to work with that came on the Volvo I bought that had the turbodiesel engine in it that ran way too hot all the time.

I do not remember seeing a 620 with a diesel engine in it, but I forget a lot these days, there was the stock blue I believe 720 diesel there, he was happy with his truck the way it is.

I see a lot of guys with 720 diesel trucks using a choke cable and a button to control their diesel engine, the Volvo I bought with the diesel engine in it was this way, pushed all the way in was the start position, pulled half way out was the run position, and pulled all the way out was the off position, the button was to warm up the glow plugs although I would do that thru a relay myself, it is the simplest way to do it if you do not have a diesel wiring harness and all the diesel components.

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Initially I'm going to use the 4.375 gears and the extra 15 inch wheels/tires for the Toyota FJ40. Not the ideal set up, but the larger tires will make things better than the 4.375 and the stock 14 inch tires, and cheaper also. This will give me a chance to work the bugs out and give me a feel for what the motor and transmission will do. I'm not 100% sure what I will end up with, but I'm leaning towards the 15 inch rim size, a little bit wider than stock, and disc brakes up front. And if I go to 15 inch rims I might go 2 inches lower than stock, if it will help with the fuel mileage a little bit. Fuel mileage is the most important thing I'm after.

 

I've read where a proper size turbo, and carefully driven, can help with fuel mileage. Hopefully so, and I can afford to get a turbo soon after getting all the bugs worked out after getting it running initially. I haven't even considered sizing for a turbo yet though. I'm somewhat familiar with what to look for in a turbo as I have a 3/4 ton 4 WD 94 Chevy with the 6.5 diesel and turbo (12 to 14 MPG, expensive). In the meantime I will take all the advice I get.

 

The diesel radiator didn't originally fit in the 620 radiator opening, but it does now. I had to open up the 620 radiator opening to fit the diesel radiator in. I opened it up a little more hoping that in the future I can fit a condenser in there. I got a used condenser from the wrecking yard for sizing purposes, but the input line was too tall for the core support. I tried to find a tubing bender locally the right size for 1/2 or 9/16 inch tube. But everything was for 7/16 or 1 1/2 electrical conduit, not what I needed.

 

I'm aware that remote radiator fillers are available, just don't have one yet, I've found them online. I'm going to wait until the radiator situation is taken care of, whatever way it happens, so that I know what to get.

 

I just looked back in my phone pictures, and it may not have been a diesel that the larger radiator was meant for. I don't have much in the way of pictures for the motor, mainly the radiator. But it was a 620. I don't know how to put pictures on ratsun, otherwise I would do so of that radiator swap.

 

I'm really counting on not having to use a choke cable for the IP start, run, stop features. I really want to get the motor running with the start, run, stop all on the ignition switch.

 

Got to go back out to the canning kitchen now. Getting it ready for next summer. Nothing like fresh picked, or home canned goods, for flavor and cheaper than buying them also.

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I am getting better fuel mileage with the turbocharger, keep in mind that before the turbo I was getting around 25 in the city and 27 on the freeway as I was going 70/75mph and was almost floored all the time, now I do not know what I am getting in the city as I have not checked, but on the freeway on my first trip with the turbo I got almost 31mpg going 75/80mph, but the big difference was I was not frustrated when I came to a hill anymore, it just went right up the hill without me changing anything, my foot stayed in the exact same spot, when I hit the hill the boost went up a little(7/8psi), and the EGTs went up a little, maybe 900 degrees at the top of the hill, but my foot did not move, no downshifting, no having to floor it, up the hill it went, and strangely it went down the other side of the hill exactly the same way, I did not move my foot, but the boost went down to 3/4psi and so did the EGTs.

Before the turbocharger was installed I would be floored in 4th gear on that hill trying to keep it at 60mph and my EGTs would be at 1400 degrees and I would be letting off the pedal trying not to go over 1400 degrees.

I have said this before and will say it again, I will never drive a diesel without a turbocharger again except maybe around town, on the freeway it will have a turbocharger or I will drive something else, the SD22 is even worse on the freeway, my first SD22 powered 720 would barely do 70mph on the freeway and when I came to a hill I would sometimes be in 3rd gear depending on how steep the hill was, I remember being in 2nd gear on freeway 101(coast freeway) in northern CA one time on a steep hill.

I have never turbocharged an SD22(3 main bearings), you need a boost gauge and an EGT gauge, these are must have things, you will likely blow it up eventually without them.

 

The DPC module(black box) is a complicated device, it controls a lot of things, even oil pressure on start up, the engine will not start without oil pressure unless one removes the wire from the oil sender/sensor, the DPC module controls start, run, off positions on the IP controller, if you are smart about electronics you might be able to set something up that will work without smoking the IP controller, but I have never heard of anyone succeeding, I have heard of a guy that used solenoids for the off and run positions.

The guy that had the Volvo with the SD25 turbodiesel engine in it that ran so hot(EGTs) when I drove it I stopped driving it for a year, that guy claimed to have got 48mpg on the freeway, but he drove 50/55mph and he used that choke cable to lean out the injection pump by pulling on it till the engine would barely run on that much fuel, it could not get hot as it was hardly getting any fuel, when I test drove the Volvo before buying it it ran hot, and he told me I drove it wrong when we finished the test drive, I fixed it so I could drive it and it has power though out it's whole operating envelope without running hot.

Edited by wayno
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Getting better mileage with a turbo is something I've heard about, but never have known someone who actually did better. This is real good news and gives me a lot more hope that a turbo will do more than increase HP. The 620 is a little bit lighter than a 720, and I am hoping that will be in my favor also. An SD-22 in an NA mode I'm hoping will be only for a short time, but money for a complete turbo set up will dictate. Depends on what I find and the cost.

 

I currently have a large diesel pickup, but it doesn't do much for me mileage wise and I can't afford to drive it very much. The best mileage I ever got with it is 15.5 MPG, and that was on a summer time freeway run keeping it at 2KRPM (it is really disconcerting to have an 18 wheeler pass me). It is about three times bigger, including the motor, than the SD-22 and the mileage shows it, but it is a real workhorse and I love it. I just wish it got better MPG.

 

I'm not any good with electronics, but given a bit of time and a good schematic I can do OK with wiring. I have plans for an alarm for the oil pressure that will let me know if the pressure drops too low. I would have to go back and re-read my notes to know for sure what oil pressure the alarm goes off at, but my memory tells me it is around 5 to 7 lbs. Not as good as the DPC as it relies on the driver knowing what the alarm is for and shutting things down ASAP (or faster), but less expensive to start with. 

 

The IP controller (looks like a wiper motor) is 12V DC isn't it? Anyway, 12V is what I've used so far and it seems to be OK and I've got the controller figured out with a special ignition switch. I also successfully tried about 9V through a resistor like is found on older vehicles.

 

I plan to get EGT and boost gauges. I put five Glowshift gauges in my Chevy pickup, and only the boost (mechanical) is still working. I used Glowshift because of price, but I will NEVER recommend them for anything now. What brand would you recommended as being the most reliable?

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I buy the Autometer gauges, the extra Pyrometer I have is part #2654 with a black face, but all my other gauges have white faces, I do not recall their part number, they are expensive gauges, I paid close to $200.00 each for both the pyro gauges I have, I got a deal on the black faced one.

My boost gauges are also Autometer, but they were cheap, when I go to swap meets and car shows I was always looking for a deal on complete pyro gauges and any gauges I might need in general, now that I have an extra pyro gauge I have not been looking anymore.

Mike you need to understand the inline injection pump the SD22/25 came with, they are vacuum controlled and when floored they all blow black smoke when stock as they are rich unless someone has messed with a smoke screw and forced them lean, under normal driving around town they normally do not blow black smoke, but when you come to a hill or try driving up a mountain pass either you down shift or you floor it and hope to not have to down shift, but since putting a pyro meter in my 521 kingcab before it had a turbocharger, I came to realize it is not good to floor them for long as the EGTs can easily go over 1400 degrees, and from what I have read 1400 degrees or more is bad, it is not a matter of if it will melt down, it's a matter of when it will melt down, a couple times in the past my diesel engine started to lose power and the water temp got very high while being floored for an extended period of time trying to get to the top of a pass, I was very lucky I didn't smoke the engine, I did not have a pyro gauge back then and the engine still runs great to this day, I am so lucky and Nissan must have built these SD25 engines to take punishment, I did the same thing to my SD22 a couple times, but nothing like what I did to that SD25 on that trip over the Grapevine in southern Ca.

 

I get better mileage with the turbocharger because I am not floored, I have got around 35mpg with both my SD22 and my SD25 engines when I drove 55/60mph, but I do not like driving that slow, on a trip if I drive 70/75mph I will get to where I am going and back home way sooner.

When driving my SD22 powered 720 on the hiways, I had semi trucks passing me all the time, it drove me crazy, that is why I found SD25 engines for all my diesel trucks.

I do not believe the DPC Module will shut a running engine down once running but I do not know for sure, but it will not let the engine start till it shows oil pressure unless one removes the wire from the oil sender/sensor.

 

I also use an RPM gauge(diesel tach), but after driving my diesel trucks all these years I could likely do without it, in 1st thru 4th gears the engine starts to sound over revved at 2600rpms, but the engine still sounds fine at 3000rpms in 5th gear, but one is close to being floored at 3200rpms in 5th gear even with a turbocharger with 3.50 gears in the rear with P195/75R14 tires, keeping in mind that I have SD25 engines, I have not drove an SD22 powered anything since around 2010/11 when I finished the 521 kingcab.

 

I know I talk too much, but because I do I hope that others learn and do not make the same mistakes I have made.

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Thank you wayno. I think it is safe to assume that Autometer has worked without any malfunctions for you. The EGT gauge I had in my big pickup was a real eye opener while it worked. The EGT temps went up really fast, and could under the right conditions come down almost as fast. The big thing I remember was how really really fast they could go up.

 

I have a Tiny Tach in my Chevy pickup. For the 6.2 and 6.5 2000 RPM seems to be the best, and I'm assuming the SD 22 is the same.

 

As far as I'm concerned it is people like you wayno that I can learn a lot from. First hand experience is the best teacher, and the next best comes from those who share their experiences.

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I have owned 2 tinytachs for my diesel engines, the first one worked great, the second one is a piece of shit and they(the tinytach place that sold it to me) do not want to fix the issue, I talked to them on the phone and they sent the piece that connects onto the injection line but that is not the issue, it's the main assembly that is not working correctly and they would not send another one of them to me, when I let off the pedal instead of the tach showing the lowering RPMs, it shuts down and goes to total hours till I step on the pedal again and start picking up speed, it is very annoying. 

My 521 kingcab diesel has an Isspro tach, it is the type that I had to glue magnets to the harmonic balancer/front pulley and then mount a sensor, that tach is great, it has been on that engine for years without a hiccup.

My Autometer EGT gauges work great also, never had an issue with any of them, but they are hard to get parts for, I tried to get another piece to weld into the exhaust manifold when I changed exhaust manifolds(when I put the turbo exhaust manifold on), in the end I had to make my own bung/mount for the sensor.

Yes the EGT temps rise fast, when I first got the 720 turbodiesel in the Volvo I could not even get up to 50mph without the EGTs going over 1400 degrees, that engine setup was a failure, but if you talk to the guy that sold it to me he would say I drove it wrong, I finally figured it out a year later after trying 3 different injection pumps, I went back to the injection pump it had on it and I went a different direction, I plumbed it differently, I went to a draw thru, it ran great except for the vacuum issue/oil sucking thru the seal issue when I let off the pedal, I kinda fixed that issue and then seen that ad for a SD22 turbodiesel engine for sale on Craigslist which turned out to be that knuclehead guy on the Nissan Diesel forums, I talked to him and figured out what my lean running issue was on the draw thru setup I had, after talking to that guy I thought about everything differently, I plumbed the 521 kingcab turbodiesel as a blow thru and piped it differently than I ever had before and it worked great, so then I took the 720 apart and copied what I had done to the 521 kingcab and it worked exactly the same, what I did was repeatable,  that is when I started telling everyone how to do it, and it is so simple, only one vacuum line changes from the stock configuration.  

What is great is that the EGTs do not run very hot on my 521 kingcab turbodiesel engine, but that may have something to do with what I have for componets, and where I put the EGT sensor, I messed up and put it right after the turbocharger when it should be before the turbocharger, but my 720 runs way cooler than it did before also and it has the sensor in the proper spot.

The 720 was/is my test rig, I ran it with and without the innercooler and it maybe made a 100 degree difference, so my 521 kingcab has no innercooler, until I take my intake system apart again on my 521 kingcab I will live with the EGT sensor mounted where it is, the engine runs great, it runs better than the 720 engine, but that engine is set up way differently and has mods I am so happy that my 521 kingcab does not have.

I am not a search the internet guy to figure out my issues normally, I figure them out by asking other diesel guys questions, or I just keep trying different things till it works, nothing I have done is original except how I may do it.

I normally am somewhere around 1700 to 2400rpms around town(city driving), but on the freeway in 5th gear I am between 2500 and 3000rpms, the 521 turbo really kicks in above 2000rpms, while the 720 power kicks in way below 2000rpms, but that engine does not operate properly above 2200rpms, well that is not true, I have to have the boost set at 7psi because if it is set at 15psi that is what I have on the freeway as a larger compressor vane/blade was installed in the turbocharger, it is pumping air into the engine at all times, even at an idle, and it spins up fast, I would never suggest doing that, the injection pump was turned up also, my 521 kingcab runs so much better without either of them mods.

Edited by wayno
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1/ Try hitting the reply button and scroll down several lines using the enter button then put a period in and add your quote one line above it. This will leave room at the top to add your own text before it.

 

2/ Or hit the + sign to the left of the quote. This will hold the quote while you add your text. Then hit the 'quote one post' flagged in the lower right. You can stack several quotes together with this.

 

3/ Start with your text then find the quote you want and click it. Not very good if on the previous page.

 

 

Place your icon above the quote on the far left and a flashing square with a cross inside it will appear. Place your icon on it and hit your delete button to remove the quote

 

 

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Thanks Mike, I edited the post using the last suggestion and it worked, I would never have figured that out on my own, I seen that box but never would hve thought to click on it and then hit delete to remove a quoted post, normally I would just left click and hold and turn everything blue that I wanted to delete, but that doesn't work here anymore.

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You can post a quote within a quote by 'saving' a quote then move inside the quote you are displaying and hit the quote 1 post button lower right and it inserts it.

 

52 minutes ago, wayno said:

Thanks Mike, I edited the post using the last suggestion and it worked, I would never have figured that out on my own, I seen that box but never would hve thought to click on it and

 

52 minutes ago, wayno said:

Thanks Mike, I edited the post using the last suggestion and it worked, I would never have figured that out on my own, I seen that box but never would hve thought to click on it and then hit delete to remove a quoted post, normally I would just left click and hold and turn everything blue that I wanted to delete, but that doesn't work here anymore.

 

then hit delete to remove a quoted post, normally I would just left click and hold and turn everything blue that I wanted to delete, but that doesn't work here anymore.

 

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Wayno, your problem with the Tiny Tach is the first I've heard of any. I will be watching mine to see if it does that. So far I have had no known problems with mine. I like that it is digital and shows RPM for every 10 RPM of the motor, which is more accurate than any analog tach I've used. Trying to figure accuracy on an analog tach for a needle that is moving between marks, often without numbers, on a background that doesn't have enough numbered divisions isn't accurate.

 

Having to glue magnets on something that spins is something I've been very leery of, centrifugal force can throw things off with a great deal of force. I have not trusted that anything glued on will stay on for a long time, so it is good to hear about your long term success.

 

The turbo exhaust manifold you speak of, is it a stock item, or did you have to make it? My stock exhaust manifold dumps out extremely close to the emergency brake cable and I am concerned that it is so close that exhaust heat will cause problems. I figured I was going to have to make a manifold for the turbo to get heat away from the e-brake cable, and of course to properly set up the turbo. I'm hoping to set up the exhaust so that it won't take much to change from NA to turbo.

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No my turbocharger manifold is not stock, it is a stock manifold that has been modified as you can see in the photos below.

Image

 

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In the center of the photo above where the bump is is where I should have the EGT sensor, but it is located behind the turbo in the photo below.

Image

You can see in the first photo how big the hole is in the manifold and how the stock exit is welded closed, this made it possible to route the turbo exhaust pipe out the stock location, in the photo below you can see the adapter I made to mount the Subie turbo to that giant hole in the manifold, notice how small the hole is, originally I thought this step down into a small hole might effect the turbo performance, but it works great, who knows it might work better if the hole in the exhaust manifold was the same size as the hole in the adapter, but I do not care anymore, it runs great.

Image

 

The adapter above is made from a flat plate matching the exhaust manifold and the mount piece off the Subie exhaust going to the turbo, when I bought the turbo from that wrecking yard I got everything connected to the turbo, the complete exhaust from the engine on both ends although i made the turbo exhaust from the turbo flange back as the stock head pipe was pointed the wrong direction coming out of the turbo.

I suspect that the diesel engine just doesn't move enough air to have the step down into a smaller hole effect the performance, if it was a gas engine I suspect I would have issues.

 

Here is the engine in my 521 kingcab.

 

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There is not a lot of room anywhere in the engine compartment, but the hood closes.

 

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The brake master is real close to the turbo, but I did make a heat shield, I also had to turn the front brake reservoir sideways as there was no room for it in the stock position.

 

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Here is a link to the thread I have about this turbo build.

https://www.nwdatsuns.com/viewtopic.php?f=13&t=1302

And here is a link to the 720 thread about all the stuff I tried to get the engine to run properly the way I drive.

https://www.nwdatsuns.com/viewtopic.php?f=15&p=69188#p69188

 

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I'm reading the thread on  that link you gave, and have some questions (if I don't ask now my memory get lost and forgetfulness will take over). Where did you get the manifold gasket from, local parts store or dealer? The dealer in Albany closed up several years ago so now the closest dealer to me is about 25 miles away. And just out of curiosity, do you remember how big the turbo that you took off was? I've never run into a turbo that needed any water to help cool it as my Chevy 6.5 doesn't have any water cooling passages for the turbo. Everything I read about the Chevy turbo says that water cooling isn't needed, but I'm not highly experienced with turbos either.

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