Backing Plate To Housing Bolt Pattern

[620slodat]

First, I have done some searching (without success), and I will continue searching as time permits. But, I have some questions about a 1982 720 rear axle brake system that I need answers for.

 

I have been told that up to the end of 1982 the rear brakes were manually adjusted, 1983 and after the rear brakes had self adjusters. What I am wondering is if they had different backing plates, and if so will the newer self adjusting backing plates bolt on in place of the older manually adjusting plates? I have a 1982 rear axle that I am assuming were manually adjustable brakes, and I am wanting to change to self adjusting brakes.

 

I'm trying to plan ahead and give myself time to find what I will need.

Edited February 8, 2019 by 620slodat
preparing for merging this thread with the thread in the 620 forum

[datzenmike]

Self adjusters were introduced on build dates starting 12/81 or approximately half way through the '82 model year which starts in June of the previous year. Confused yet?

 

2wd and 4wd backing plates are different part numbers and self adjusting brake backing plates are totally different from the manual ones.

[620slodat]

Thank you for the reply DM. It is a 2wd diesel frame, but I don't know when it was manufactured. Only know that it was licensed as an 82. So, what I understand is that I MAY be in luck and have self adjusters on that rear axle, or I MAY be out of luck and have the manual adjusters. The only way to know for sure is to pull the wheels and drums and look. I'm not really ready yet to pull anything, but in order to satisfy my curiosity I'm going to have to bite the bullet and pull things. Thanks for the info!!

[datzenmike]

If you have the manual adjusting brakes there will be a large oval rubber cover over the clips that hold the adjuster on from the back of the backing plate. And enough room to slip a screwdriver in from the back to lever the star wheel and adjust the brakes. On the self adjusting ones this isn't the case

[620slodat]

Thank you for this info DM. I will go out there and see what I have. It will be good to know and not have to tear things down.

[620slodat]

I couldn't take the suspense, I had to brave the cold and possibly rainy weather and see what I have (snow above 500 feet and we are at just over 200 feet. there was icy snow on the windshield, roof, and rear window of the car this morning). What I saw on the axle is just like the pictures I've seen of the manual adjusters for the brakes. So, I guess it is safe to say that I have the manual adjusters. This frame apparently is from early 82. The question then is, will I have to change the complete axle housing, or just the backing plate, if I decide I want self adjusting brakes? 

[wayno]

I would not worry about it, my brakes work fine on all my trucks and as I recall only 2 have the self adjusting type rear axle, I only adjust mine when the pedal gets too close to the floor which is years on most my vehicles.

Also as I recall the self adjusting axles have rear drums without the sunken section in them, I would likely have never let an axle like that go as I also would rather have self adjusting brakes, but to tell the truth once these axles get to a certain age I doubt the self adjusting part even works anymore.

That frame has had nothing exchanged from it except the front hubs I used to make it a roller, I did remove a couple parts(brake line stuff mostly), but I didn't replace them, they just are not there anymore.
This is the type of brake drum you likely have.

I believe this is the type of brake drum on self adjusting axles.

I suspect you can remove the backing plates from a newer axle and put them on your axle, but that would require removing the axle from the backing plates as the newer axles are wider, and it would require setting the rearend end play and other such stuff, it's easier to just put a complete axle in.

I have never seen an 82 or even an 83 with self adjusting rear brakes, and I have only seen one 84 with them at a wrecking yard.

A 1985/86 axle is wider, they will likely fit in your 620 box fender wells, but the size of the tires will come into play, you will not be able to use large/fat tires as they will rub the fenders, also you will not likely be able to use aftermarket rims as they will stick out of the fender wells front and rear.

Edited February 4, 2019 by wayno

[datzenmike]

wayno, I also heard that the self adjusting axles are wider or overall the rear end is wider. 

[wayno]

Yes, I believe the 1985 and I know the 1986 is wider, I have 1986 axles in the 520 and the 521 kingcab and the 1980 dually now, the work truck has a real Nissan dually axle in it, I cannot use the real dully axle in any of my diesels because I need 3.5, or 3.3 gears in the rear, while the best the C200 had was 4.1, that just doesn't work with low RPM diesel engines.

It took me years to find three 1986 truck axles as I didn't want to pay wrecking yard prices for them, I only bought one dually axle at a wrecking yard(first one), all the rest of the ones I have came from craigslist or that guy I got the 1986 Nissan 720 cab/chassis frame from under the work truck now, that truck came with an extra dually axle, I believe I have six of them now and 2 are toast/broken in some way, that total includes the one under the 521 work truck.

Edited February 5, 2019 by wayno

[620slodat]

Wayno, I do have the brake drum that you show in your first pic, not the drum shown in your second pic. I would like to have self adjusting brakes, but that doesn't mean I can afford to do the swap. If I find something that I can afford I will swap, if it is physically possible. I will leave the brake rebuild until the last in case something affordable comes up. In the meantime I will continue to look and search to see if the swap to self adjusters is possible.

 

In the meantime, I have found a 1978 King Cab, but it has rust through in the rockers and floorboard. So I will repair the rust in the rocker part of the King Cab, and combine the standard cab and King Cab. The process I will use is to be determined yet. I'm doing a lot of thinking about this, and since I live next door to a professional body guy who apparently knows the older cars real well I'm going to see what he says is the best way. 

[wayno]

Making an extended kingcab to fill the gap between the cab and the box is not easy, it would be much easier to extend the box, but we work with what we have available.

It's a lot of work to do what you just mentioned, it took me over a year to make my first 521 kingcab and I didn't do a lot of the body and paint, I just put the cab shell together and tried to do the body filler.

Having a rear axle with self adjusters is nice, but they don't always do what you want them to do, fact is I rarely hit the brakes when I am backing out of my driveway, I just put it in first and let out the clutch even though I am coasting backwards, you have to use the brakes going backwards for them to work/self adjust, not many go backwards that fast to actually make them work.

 

 

 

 

Edited February 7, 2019 by wayno

[620slodat]

I realize that doing bodywork might take some time, however I have lots of that. It's been 10 years now since I had to go on disability, and sometimes I go stir crazy. Often I don't have the funds to do what I really want, so I usually make do with what I can afford. That doesn't stop me from wanting certain things though, and sometimes I can find a way to finagle a way around some of the larger costs. Knowing the information is very cheap, and having the correct information can help greatly when something wanted comes up at a real good price. That's the ratsun way isn't it? 

[wayno]

You just need to understand how long this will take you, it takes time to make a kingcab, especially if you want to do it right, it would be much easier to extend the box to fill the gap.

 

[620slodat]

I understand that it is much easier to build a longer bed, and that modifying the cab could possibly take longer. I am definitely going to put a canopy on the bed (I am a canopy user), and I already have one. So, this knowledge dictates everything that I do. All the parameters for bed size have to be within sizes available in canopies. Also, the extra space available in the King Cab is needed for me to be able to stretch out (I need to be able to stretch my legs occasionally because of my disability). Being able to stretch out was a big concern for me with the single cab.

[wayno]

Legroom is the very reason I have kingcabs.

Anyway you look at it, you have a lot of work ahead of you.

I would be also be looking for a non-tilt steering column out of a Datsun/Nissan 720, your going to need it, it likely will a little loose in your 620 column bracket, but you can use rubber strips/sheeting cut into a strip to snug it up, I have tilt columns in my 520 and 521s, but it is way more complicated to install, cutting of the mount bracket and certain compromises have to be made to get it in there while the non-tilt column basically bolts into the dash existing mount.

Also if done right the existing 720 firewall steering column mount plate can be cut down(not cut off) and used to stabilize the column base at the firewall and make a decent seal, I cut that plate off all my columns because I didn't know any better and the 521 pedals made it difficult to deal with that plate.

 

[620slodat]

Thank you for the info about the 720 steering column. I definitely am going to get rid of the "spear". What I end up using depends on what I find. I've looked at a 720 tilt column, and have a question for you. Under the hood of the 720 is what is supposed to be a collapsible portion of the column. It looks like it is built to collapse, but it is tight enough that just casually trying I couldn't get it to collapse. Will that section collapse? Can the power steering collapsible section be extended any if I end up going with the power steering column and use the manual box? The manual box is shorter than the power box, and has a smaller input shaft also.

 

Currently I am thinking that the manual box is what I will use, but I am looking at all options. Maybe manual box and electric power steering at a later date? The space on the motor for a pump is limited, it probably can be done but could possibly take up valuable space needed for something else (maybe AC?). The manual steering gear box is on the frame I got from you, but the bearings feel rough. If I end up going with rebuilding the manual box and using the power steering column I have a way to address the two sizes of shafts. If I use the power steering box instead can the power box be used as a manual? If it works to use the power box as a manual box I am considering looping the inlet and outlet hose to keep dirt out and lubricant in. If I don't have a power steering pump to work against can the power box be easier to use than if the pump is in the equation?

 

I need information, whether I go with tilt or not, power box or not. More information will help me make informed decisions. There will be more questions as I think of them, but for now this is enough. These questions are not just for Wayne. If somebody else has some pertinent information by all means please chime in.

[620slodat]

Mods, I am considering making this into a build thread since I know I will have so many questions about other areas besides just backing plates. The big reason why I haven't made a build thread yet is that I expect this thread to be very slow at times. But, I just finally got to the end of Charlie69's thread about his 521, and it spanned many years. So I need opinions. I am putting a 620 cab and bed onto a 720 frame, and the SD-22 diesel motor in also, but because I am on a very limited income things may get very slow at times due to lack of money at the moment. Do I make this into a build thread, and if so should it be in the 620 forum or 720 forum?

Edited February 8, 2019 by 620slodat
added info

[datzenmike]

 I think 620 would be fine. You can start one with a new title and I can move this post into it... or not and start fresh. OR you can change the tile of this post and I'll move it to 620.

[wayno]

I wondered why you didn't use your original thread for all these questions and as a build thread, you can always change the title of that thread.

https://ratsun.net/topic/74805-introduction-for-620slodat/?do=findComment&comment=1592892

 

The columns do expand and collapse in the engine compartment, but they need to be convinced to move sometimes as they are 30 something years old and don't like change.

As for steering columns, I do not know if the power steering column will stretch far enough to connect to a manual steering gear as I don't recall ever trying, but there is one benefit/plus to using the tilt column, I believe all your column electrical stuff like turn signal assemblies and whatever else the 620 has will bolt right on to the tilt column like it was made for it, as I recall the tilt column tube and the stock 620 steering column tube are the same size, this is true for the 320/520/521 columns, I do not know about the 620 column as I have never owned one, but I suspect they are all the same sized tube.

The drawback for tilt column is that it doesn't bolt into the existing 521 or likely the 620 steering column bracket, it has it's own mount assembly bracket which also includes the tilt adjustment mechanism, at that time I seen no way to mount it to my 521 column bracket, that was 8/9 years ago, I have not looked into it since.

Also the columns are made different, the power steering columns have the rag joint near the firewall, while the manual steering columns have the rag joint at the manual steering gear itself, I tried using a manual column on a power steering gear once, the rag joint hit the upper control arm, it didn't work, that is why the rag joint is near the firewall, also you will need all the power steering stuff to have power steering, all my engines right now have home made power steering assemblies that I believe I showed you while you were here.

For now if you want to keep it cheap just stick with manual steering, I believe I have another manual steering gear if you need it, there is not much to a non-tilt column, but your 620 column hardware like the turn signal assembly and other such stuff will not likely bolt onto that column as it is too small around, but I am pretty sure it will bolt right into the 620 steering column mount bracket.

 

 

 

[620slodat]

Wayne, this thread was meant to be specific to the 720 rear brakes. But, it morphed into what it is now. That is why I'm looking at making changes. If I use the thread in the 620 forum as a build thread it will make for a better fit as I will be asking many and diverse questions. 

 

DM, can you merge this thread into the existing thread in the 620 forum? I'm not sure how to make a thread title change, but this thread title can be dropped. I don't know how to change titles, but "and his diesel build" can be added to the existing thread title. I have made changes to the first post in this thread to explain that it deals with the 720 rear axle brakes.

 

 

[620slodat]

Wayne, there are not very many 720's in the local wrecking yards. The only ones I can remember are 4 X 4's with tilt columns, so I will pick up a complete tilt column and steering box. Needing to possibly modify mounts for the column doesn't bother me. I will have to see if that section of column can move/expand, and if so by how much before I pick whether I use the manual box or power box. It is good news that the part of the column protruding from the dash is the same diameter as the 620 column. I am used to multi-function turn signal stalks so maybe I can find enough parts with the 720 column to use the 720 multi-function stalk parts. If not, I have all the parts needed to put the 620 turn signal, key switch, and cover onto the 720 column. 

 

We will see what comes from this.

[wayno]

I cannot remember everything, my posts would be even longer if I could.

As I recall the 4WD 720 trucks are built differently and have the rag joint at the steering gear, that will not work on a 2wd unless you grind upper control arm corner out of the way, this is how I know as I did that, but it still hit as when I hit bumps I could feel it hit the steering shaft, so I found a 2wd column and all was good.

You need a column with the rag joint near the firewall and the knuckle joint at the steering gear.

To go from manual steering to power steering you will need the steering gear, the power steering lines going to the passenger side, the power steering pump and reservoir, the power steering setup that came on diesel engines was right next to the injection pump controller near the oil pan with an adjustable pulley to adjust the belt/keep it tight, the guys on the diesel forums asked me for photos of it to see what it looked like as it is a rare option.

This is why I made my own power steering setups, when you were at my house I believe you looked at my 521 turbodiesel, there was not a lot of room in that engine compartment, you will have the same issue, it will be tight in your engine compartment.

My 521 diesel has a Hardbody pump and reservoir which are separate as I needed everything to be under the hood, maybe I used a Pathfinder pump, all I remember for sure is not all Hardbody/Pathfinder power steering setups will fit the 720 power steering gear, everything has to be the right part for it to work, I made 6/7/8 power steering setups over the years for diesels, and none of them were made the same, the only common part was the steering gear and the power steering lines going to the passenger side, I had to find pumps and reservoirs with the proper fittings to make it work.

When I made all these power steering setups it was when there were sometimes 5/6 Datsun/Nissan 720s in each PNP wrecking yard and there were 7/8 wrecking yards in the Portland/Vancouver area, now there are 3 yards and it is getting rare to see more than one Datsun/Nissan 720 in any of them, as I recall there was one in each of the Vancouver and Foster Rd yards, and I recall both having tilt columns and power steering, but nothing is cheap in them yards anymore, I suggest you get your truck pot together with manual steering and worry about power steering later, perhaps a cheap setup will come along before you can get it on the road.

 

You can change the thread titles on any of your threads by going to your first post and using the full editor.