My 1969 Datsun 521 kingcab diesel

[wayno]

Here is my 1969 Datsun 521 kingcab, I never started a build on this truck as it was basically done when I joined NWD.



Here is the SD25 diesel engine it has in it.

The front with tri-pole headlights.

At one time it looked like this, but I didn't like it, and I didn't think the engine could move it down the freeway at hiway speeds, so I made it the 2wd it is today.

I hauled it to blue lake before converting it to 2wd with the 720 diesel dually.

So why I started this thread on this truck is because of this, on August 28th, 2013 I bought an H190 LSD from the wrecking yard along with some other stuff I have used already, well today I installed it in the diesel kingcab, I didn't finish everything yet, but I did drive it down the block.
It's not as tight as I remember, I am hoping it don't howl or anything like that, it sounded alright, but I only got into second once, I have to put the park brake cables in it tomorrow.

[Justinberni]

I wanna find a h190 LSD for mine, but anyone who has one wants a fortune, you got lucky with that one Wayne!

[wayno]

I know I got lucky, I actually had to convince myself it was a H190 LSD, I just thought to myself it wasn't what it seemed to be, but it was, I was very lucky.
Someone had dropped the rear part of the suspension and took the shackles, but left the 3rd member there, I was real lucky.

I wanna find a h190 LSD for mine, but anyone who has one wants a fortune, you got lucky with that one Wayne!

[Indy510]

The cab extension is really impressive ... Do you have any tips for welding a roof without warping it from the heat?

[Taterhead]

^^^ I think I have read somewhere Wayne said he did it by welding a lot of spot welds 3-4 inches apart. I'm sure he'll chime in.

[wayno]

The cab extension is really impressive ... Do you have any tips for welding a roof without warping it from the heat?

Taterhead is correct, it is done with a lot of tack welds(spot welds) that are done about 4 inches apart, so you tack the middle on the front and back once aligned, then I do all 4 corners so it is held in position, then I tack it every 4 inches all the way around, once around I tack it in between each tack weld which is still 4 inches apart until I get all the way around, then I start skipping welds/tacks making sure I am at least 4 inches ahead of the last tack/spot weld, I do this till the welds have no room between them for a tack weld, then I am done.

The point is to be able to touch the spot you are going to tack with your bare hand, if you cannot touch it, then it is to hot and will eventually warp, this technique works good on a large area like the top of a truck like in the photo above, but it doesn't work if your just doing a small repair like filling in a marker light hole, a door handle hole, or an antenna hole, them size repairs need to cool off between a couple tacks, you have to be able to touch the metal your working on with your bare hand, small holes you do a couple tacks and then walk away for a while.
Another thing is that the metal has to be clean of all paint, bondo, primer, dirt, it needs to be clean bare metal on both sides(top and bottom), otherwise it will make holes or not bond.
The photo above was done with gas, so it looks cleaner although it might not have been quite hot enough, but I have had no issues with that truck roof so far(the 520KC), but the red 521 kingcab with the stepside box was tack welded together with flux-core wire, almost all my welding is done outside with flux-core wire, that whole truck was done with a cheap Harbor Freight mig welder.
I did forget to mention that the pieces of metal I tack into place are other 520/521 tops, it takes pieces of 3 cabs to make one extended cab, I tried to use a flat piece of metal on the red 521 kingcab, and I could not bend the metal at the sides above the doors, it kept caving in the top trying to bend it to the correct shape, so I covered the damage with a bigger piece of top from another 521, if you use a flat piece of metal, it will need to be bent/shaped before attaching it to the top of the project cab.

[wayno]

Well I have been driving it around for a while now with the LSD, I have noticed one thing, every time I make a right or left turn at an intersection, the whole truck vibrates if I am accelerating, the inside wheel is basically burning out, but it doesn't do this if I am coasting or light on the pedal, only when I put my foot in it.
I also have had it on the freeway also, it makes no noise.
The truck looks better with the wider 1985 axle under it, the wheel/tire are not sunk in 3+ inches now, at least I think it looks better.

In all the photos in the post before this one you can see the rear wheel is fairly deep into the fender.
I think the next thing I need to do to this truck is to notch the rear frame and put 720 4X4 leafs on the back and then lower the front to match, right now if I hit a speed bump to fast, the axle hits the frame, I have no bump stops back there.
Not a lot of clearance, been this way for a few years now.

[draker]

That's the same behavior of a welded diff when turning.

[wayno]

That's the same behavior of a welded diff when turning.

I don't know, I never been in a car/truck with a welded diff, but it only happens when my foot is in the pedal, if I just lightly give it pedal there is no vibration.
I like driving this truck, it has enough power to make me happy around town, but on the hiway it lacks power when I come to a long up hill grade, anything more than a mile and it starts to heat up and lose speed, otherwise it is a great truck except for the rear axle clearance and the engine noise, I suppose I could sound deaden the interior also, lots of stuff to do that I never seem to get too, I should make a list.

[yello620]

Did you put LSD friction modifier in when you filled the rearend? I don't actually know if it needed in a H190, but EVERY other LSD I have ever worked on needed it or it would have issues like you described.

Nice score finding a H190 LSD

[wayno]

Did you put LSD friction modifier in when you filled the rearend? I don't actually know if it needed in a H190, but EVERY other LSD I have ever worked on needed it or it would have issues like you described.

Nice score finding a H190 LSD

Yes I did if LSD friction modifier is oil made for LSD rearends, every Nissan LSD I ever seen was marked with a orange sicker saying to use LSD gear oil except this one, so I went to the parts store and asked them, I just used Valvoline limited slip gear oil, maybe I should have bought more expensive gear oil, but that was what the guy grabbed and showed me.
I suspect that this LSD was put into that truck by someone that had found it like I did, it's hard to say what oil was in it before I found it.
It doesn't vibrate any other time except when making a sharp turn when my foot is in the pedal, otherwise it is smooth and quiet, a long time ago I had a Triumph Spitfire that did this, that one had a chunk of metal that had got stuck in the spider gears and jammed them up, that one I could hear the squeal of the inside tire when making turns, the car itself didn't vibrate.

[wayno]

Well I decided to turbocharge this diesel truck also, it just needs more power.
So this is where I started.

This is where I was a couple days ago.







I started with this.



I used this Subie turbocharger.



I made this adapter.





Today I piped the oil and water to and from the turbocharger, I then started it and warmed it up, the intake is not piped yet, I was just running it like normal, but the air was really coming out of the turbine, especially when I revved it, I hope it is enough to build boost.
Tomorrow I will install the pyro probe in the head pipe and then install the boost gauge so I know what is going on.
I am happy how things are going so far, it will be interesting to see if cutting a hole in the side of the exhaust manifold really works, I really didn't like that setup when I first got it on the SD25 engine that is in this truck, I thought it looked like a backyard job, and in reality that is exactly what it is, but when I removed the turbocharger that was on it and looked at it, I thought this actually might work without that huge turbocharger that was on it, I seriously doubt that it actually built any boost the way it was as the waste gate was wired shut, so I assumed that they were having boost issues(like barely getting any), in my opinion the turbocharger was to big, I put a Subie 1600cc turbocharger on it that is about the same size as the one in my 720 turbodiesel.

[noflers]

Now that's a unique manifold. One day I'll have enough spare parts to just decide one of my rigs needs a turbo. haha

[wayno]

I got a lot done today, I started by installing the bung for the ETG gauge probe, then I installed the boost gauge, I then took the 720 turbodiesel and started trying to find parts to pipe the turbo to the intake, I found all that piping at the hardware store.
I put it all together and then started it, it seemed to idle and rev in the driveway alright, so I took it down the block, the waste gate was not piped yet and I seen 15psi briefly, I turned around and went back home, I then proceeded to pipe the waste gate to the turbine compressor along with the boost gauge, I then took it for a drive again, I didn't see much more than 7/8psi after that, but the first thing I noticed was that when I pushed the pedal down part way, it would pick up speed and start building boost, the more boost the faster it accelerated, I would have to let off the pedal as it was acting like it wanted to run away, is that what they call surging?
Anyway it felt weird so I went to the parts store and bought another tee fitting, drove home and put that tee into the compressor line that controlled the waste gate and boost gauge, I piped that tee to the vent line for the injection pump, so my thinking is that when it builds boost the injection pump sees the boost and floors the injection pump, the more boost the richer it is, the richer it is the hotter it runs, this is the issue I had with the 720 turbodiesel, it ran so hot I thought I would smoke the engine, when I pipe boost to the vent line the injection pump has boost on both sides now.
So I took it for a drive again, it had more power and the surging was gone, but it doesn't have the power it had on the first drive, so now I need to buy two controller valves, one to control how much boost the vent line sees, this should get me more power by letting the injection pump be richer, but not as rich as it was on that first drive that it was surging, the other control valve is for the waste gate control, I want a little more than 7/8psi, I can close it and get at least 15psi like I seen earlier.
After I did all this and drove it around without valve control, started to clean things up, I re-did the piping for the injection pump control lines as they were just lying around on things, then I started thinking about an air filter, there is not a lot of room left in the engine compartment, so I decided to move the battery back a few inches, I cut a hole in the inner fender to make room for the stock diesel air filter housing, I mounted it and was going to use ABS pipe across the front of the engine between the compressor inlet and the air filter neck, that was when I realized that I might be able to use 2 stock rubber inlet hoses as each end had an angle, I could hardly believe it worked so well, and I can close the hood.
So here are the photos.































I need to get the control valves and I also need an exhaust system, right now the exhaust is pointed at the ground right next to the starter.

[wayno]

I made a simple exhaust system that dumps just below my seat then took it for two drives.
The first drive went alright till the pre-filter(fuel filter between the tank and fuel pump), luckily I had another fuel filter in the glove compartment and the tools needed to change that filter, I drove back home, it would blow black smoke when accelerating in 1st thru 4th gears, it was too rich.
The next drive I disabled the waste gate and took it for a drive, I had way more power, but I could not hold a steady speed on the hiway, it was either accelerating or decelerating, there was no middle, I drove it back home and put the waste gate back in the loop.
I am waiting for the control valves now, it likely will do no good to change anything till I have them installed.
I think the waste gate acts as a buffer, it is not something I planned on or actually want, but I might not have a choice in this.
I did notice that once up to a steady speed I have no boost, it only creates boost when accelerating, my 720 has boost all the time, that is likely why I don't get that good of mileage in the 720, I only have the 720 to gauge how this 521 engine runs, this one is different, the 720s intake turbine was modified to except a larger intake vane to build up boost at lower rpms, this 521 turbo has the stock Subie intake vane, it doesn't build up boost the same, it is something I will have to get used to.

[wayno]

So I have been driving this around town for a few days now, I put a boost control valve in between the turbine outlet and the waste gate this morning, I can get almost 10psi now and I have not even tried adjusting it yet, I pulled it apart to understand how it worked, and I guess I was close when I put it back together.
I also added to the exhaust pipe to have it exit closer to the rear axle, it is a LOT quieter now.
I have come to the conclusion that I might not need a control valve between the boost source and the vent line on the injection pump, I have not seen any black smoke behind me while accelerating since configuring it the way it is right now, this truck is running real good right now.
I am thinking about driving to Jrocks shop get together in the morning as a 220 mile test drive, hell I got this kingcab diesel going 5 years ago and within a week of getting it going I drove it to Orange CA to pick up a bunch of windshields without hesitation, I think differently now, how sad is that.

[DRIVEN]

That install is packaged very nicely. If the PVC wasn't PVC it would easily pass for factory. Great job!

[Laecaon]

The turbo to brake MC clearance is a tad scary to me. Too much heat possibly.

[DRIVEN]

I noticed that as well but figured he was already taking care of it.

[wayno]

I have been thinking about a heat shield for that area, I also should re-route the brake lines to the other side of the master as they are really close to the turbocharger, but I just wanted to see if this was even going to work, well now I know.

I drove this truck to the Jrock shop get together today, it was around a 220 mile round trip, the engine ran flawlessly, I should have done this years ago, but I only learned how to do it the way I did it in the last year.
This thing ran awesome, I mostly went 75mph, I was turning 2800rpms, my exhaust gas temps were at 700 degrees, and I was at 5psi boost on level ground, if I slowed down to 65/70mph the EGTs went down to 650 degrees, and I had 3psi boost, if I wanted 80mph I had to start putting my foot into it and the EGTs went up to 800/900 degrees and I had around 8/9psi boost, at the faster speeds my water temp went up a little, almost 3/4 of the way up the gauge when normally it is just past half way, but when I backed off it slowly dropped to normal.
What was really awesome was how it drove, where ever my foot was is how fast I was going, if I was going 75mph at 5psi boost and I came to a hill, I just kept my foot right there, and as I started up the hill the boost would slowly climb higher depending on how steep the hill was, but it kept up 75mph no matter how steep the hill was without even moving my foot a little, but the EGTs raised when going up the hill and they never got above 1000 degrees, when I went down hill I had to keep my foot still also, it kept going 75mph, but the boost dropped to 3psi and the EGTs also dropped, but it kept going 75mph down the hill, a cruise control would work great on this truck now, normally when I would come to a hill I would have to start getting deep into the pedal to try and keep my speed up, most the time I would end up being floored and slowing down, but when the EGTs got to 1300 degrees I would start letting up, and when it got to 1400 degrees I would let way up, to go 75/80mph in this truck I was almost floored all the time and it was hot all the time.

This thing is awesome, I could even speed up going up hills, I had it at 90mph once, but backed off because this was a test drive and I wanted to get there and back without breaking down, I forgot to write my mileage down when I filled it up yesterday, but I think I used around a half tank, maybe slightly more, I believe I got real good mileage, 6/7 gallons for 250 miles of driving between yesterday and today, I will fill it tomorrow to check, even if I used 8 gallons I still got over 30mpg going 75mph.

I will drive it a little more before making my decision on the 720 turbodiesel that has the draw thru setup instead of the blow thru like the 521 above has, but I am pretty sure that one is going to get changed back to the way it was and I will pipe it like this 521, I didn't know 6 months ago what I know now, otherwise the 720 would never have become a draw thru even though it helped me learn what works and what doesn't work.

This thing drove awesome today, I don't believe I am going to change anything on it, sure I can turn the waste gate control valve to give it more boost, but right now I don't want to screw up a good thing.