New World Datsuns...

Well it doesn't work, the valve will not release the vacuum in the system, there is not enough vacuum to make it work.
So now I have been playing around with a spring that will help it open, I am able to hold the spring in position where I want it and then suck on the hose where the vacuum is supposed to open it, it is a lot easier to open the valve with the spring helping, somewhere there should be a happy place.
I am thinking that if I get it just right, the spring will help it open, but when the turbo kicks in it will not be strong enough to keep the valve from closing.
I will think about it some more tonight.

This is what I came up with over the last hour, kinda primitive, but it will likely tell me if I am going the right direction.


I can easily open it by just sucking on the end of the hose, it was very hard to open it before
I will try it out tomorrow.
I don't see how that spring could get out of there and into the intake system, I don't think there is enough room for it to get by the valve, but there is nothing holding it there except the spring tension, I might use a zip tie as a safety.

Well I could not help myself, I took it for a drive, i believe I need to put some washers between the mount and spring to help it open easier, I still have the boost I had before, but it seems I have slightly less vacuum, when I rev it the hose doesn't collapse anymore, but it does flatten a little, so I need to keep adjusting till I go past where I want to be, or till I get to where I want to be if it is possible with this particular spring, I am making this shit up as I go.
I just had a thought, I wonder if I can hook this line up to the venturi that pulls the rack back to idle, I wonder how much vacuum is in that line, I will think about that if the way I am doing it will not work.

That thought I had last night worked, I connected the part of the valve that is supposed to open when is sees a vacuum to the venturi that controls the throttle/injection pump rack, but there isn't enough vacuum there to work the valve like I was hoping, so I still had to modify the blow off valve to make it work.

Well I worked on this most the day, I think I am making progress, I made another taller one of those spring holders so it would be adjustable, I adjusted on that thing all day, I think I have it close now, but it is blowing off boost at 7/8psi which is annoying, if I set it to not blow till 10psi, it will not open when vacuum is created, but at 7/8psi it opens and doesn't create but 1 or 2psi vacuum, so for now I will drive it this way and fine tune it if I can.
I also had to remove the smog/smoke screw, I wasn't getting enough fuel, and when I went to adjust it I found out it was already open as far as it could be without removing it, so I removed it, it made a noticeable difference on the hiway.
I have run into a wall now, I believe that I am hitting the governor, I thing this injection pump might be from a forklift, or the guy that owned this engine before me had the governor set for a low rpm because he didn't plan on revving it that high, I need it to rev to 3000rpms just like my 521 kingcab diesel does, not 2500rpms like this one does, the stock automotive governor is 4000rpms, forklifts are generally around 2800rpms, I really have to put my foot in it to get it over 2500rpms.
Here is the air filter to throttle body

Throttle body to turbocharger

Turbocharger compressor to blow off valve to intake

Little farther back

Waste gate is locked shut, it is so tight it cannot move

Modified blow off valve, but this modification is to help it release the vacuum created when I let off the pedal

It's adjustable now

I need a smaller battery, this one doesn't fit very well

Remote oil filter, I will likely put the oil filter back where it belongs, as why I did this remote didn't work.

I now am in the process of getting everything working in the cab, I fixed the heater blower motor, it has one speed right now, HIGH.
I cannot figure out why the radio will not come on, maybe it got damp inside and that ruined it, I will try to see if it has power tomorrow.

I know this thread is pretty one-sided but I just wanted to let you know I'm watching.
Carry on .

DRIVEN » Thu Mar 03, 2016 10:46 pm wrote:I know this thread is pretty one-sided but I just wanted to let you know I'm watching.
Carry on .

Thankyou, I don't expect many to be interested in diesel engines, I write all this for others that have diesels that may read this in the future, but I also put it all down so if I have to I can come back here to remember what I did and have tried to do so I don't repeat mistakes I have already made.

I read it all too. Im always trying to think of something to help you, but never do...

What about using an aluminum elbow instead of silicone, then it wouldnt collapse.

Laecaon » Fri Mar 04, 2016 5:01 am wrote:I read it all too. Im always trying to think of something to help you, but never do...

What about using an aluminum elbow instead of silicone, then it wouldnt collapse.

The problem isn't the rubber hoses, it's the fact that there is enough vacuum in there to collapse the hose in the first place.
That vacuum pulls oil thru the seal of the turbocharger into the system/charge and feeds it into the engine the way I have it set up, there is not enough making it into the engine to make it smoke right now, but one day it will flow thru the seal fast enough to empty the oil pan, like in a pass when I am coasting down hill for a long time, and have vacuum for a long period of time, in theory it could empty the oil pan, and if it happened at night, I would not be able to see the smoke till it was over with.
I did consider using metal or ABS piping, elbows and only using rubber to make the short connections, but I pulled it apart to change something and seen all that oil in the tubes and realized I had another issue.
I remembered hearing about TDI engines in the past feeding off the engine oil causing a run away, the engine would just scream until it ran out of oil or blew up, I seen videos of it, I don't want or need them types of headaches.
It's the design of the throttle system that makes it a pain to turbocharge these engines, the throttle is run by vacuum and a butterfly valve with a venturi right nect to it that creates vacuum to control a very sensitive injection pump rack, butterfly closed creates a lot of vacuum and pulls the rack to the idle position, if I put my foot on the pedal and open the butterfly I have less vacuum because the butterfly is open, so the rack moves to a more rich position, when the engine is off(not running), the injection pump rack is in the floored position because it has no vacuum, if I could have thought of an easy way I would have just modified the injection pump to control the throttle with a traditional cable, others have done it, but they said that the engine is basically either floored or at an idle, there was no middle ground, but they didn't care as they were racing them, not trying to drive on the roads with other folks.
So for a couple photos
See the butterfly is closed in this photo below, if the engine is running all the air goes thru that little venturi/hole next to the butteryfly creating a vacuum signal thru that hose connection on the outside of the throttle body that goes to the injection pump rack.

In the next photo the butteryfly is open so there is less air going thru that venturi/hole so there is less vacuum in the hose going to the injection pump rack, this creates a richer fuel situation.

So vacuum pulls the rack to an idle position.
So if you put a turbocharger in front of the throttle body that venturi/hole hardly ever sees a vacuum signal because it is always pressurized, so the injection pump rack thinks it is floored most the time, so it runs rich all the time and exhaust gas temps rise dramatically, the only time it sees a vacuum signal is when the butterfly is closed and a lot of air is rushing thru that small venturi/hole, it is pressurized air, but it's not pressurized on the otherside of the hole because the butterfly is closed.
So I put the throttle body in front of the turbocharger this time, this creates another issue, when the butterfly is closed that turbocharger is still spinning, it's trying to pull air from somewhere, since the butterfly is closed it sucks the rubber hoses flat and also pulls oil thru the turbo seal, but the throttle body venturi signal is a clean signal now, the rack is only floored when my foot is floored, so the injection pump rack is not running rich all the time, so the EGTs(exhaust gas temps) are reasonable, this is why I bought that particular blow off valve, it is supposed to see vacuum and open when it does see vacuum to let air in and not let oil get pulled thru the turbo seal, and the turbo itself is close enough to the throttle body to pull enough air thru the venturi/hole to create a vacuum signal there to pull the injection pump rack to the idle position even though air is being let into the system ahead of it.
It's all a balancing act, I am trying to do something that very few have ever succeeded in doing without major issues, lots of threads get started about this, but there is never a happy ending, the threads just die like all them VG30/V8 conversions in our little trucks started by newbies.

Well I did some other stuff to the truck today, I figured out the reason the radio wasn't working was because the battery power wire wasn't connected, so that is working now.
I also got the engine cut off/start working, I was a little surprised as it had not been working for me before, well it only worked for a little while and then quit working again, this issue kinda bugs me, it works fine when not connected to the injection pump, but when I connect it to the injection pump either it will not start, or it will not turn off, I guess it's better if it starts, I can always kill it by putting it in gear and letting out the clutch.
I went out and played with it again, I found a spot were it would barely shut down and it would barely start, it was then I realized that maybe this pump will not work with this engine as the injection pump controller doesn't seem have enough throw, I don't get it, seems like they would all be the same.


An hour later below

So I modified the injection pump controller arm and gained an eighth inch throw, that will give me a quarter inch longer throw total, I will install it tomorrow and see if it will work.
Stock arm shape

Stock arm with stock rod going to injection pump

Modified arm shape

Modified arm with modified rod going to the injection pump.

I hope this works, otherwise I will have to use a choke cable to shut the engine off, I hate shit like that.

Well the modified arm didn't work, it's like the arm isn't long enough and jams, so I gave up and removed the arm, unplugged the controller and put in a hood release cable with a few home made parts to shut it down, it works great.
I might be re-timing the injection pump tomorrow, I have been talking about how the engine acts on the diesel forum and how my 521 diesel engine acts way better, a couple of them suggested that I might try that since I have tried a bunch of other stuff without any positive results, I can always put it back.
Middle lever is the kill cable, to its left is the fast idle cable, and to the right is the propane injection switch which I have not gotten to yet, it is still all hooked up, but I want everything else to work correctly before I focus on that.

Connection to the injection pump.

Looking down on the connection, I made that piece from scratch.

It is really easy to use, pull it out and it dies, let go and it automatically goes back to the run position all by itself which is an unrealized bonus.
I need to make my own vacuum release valve, I thought about trying some PVC pipe, a spring and a ping pong ball, but I could not find a ping pong ball around here so I moved on to something else and will think about it some more.

wayno » Thu Mar 03, 2016 10:08 pm wrote:

DRIVEN » Thu Mar 03, 2016 10:46 pm wrote:I know this thread is pretty one-sided but I just wanted to let you know I'm watching.
Carry on .

Thankyou, I don't expect many to be interested in diesel engines, I write all this for others that have diesels that may read this in the future, but I also put it all down so if I have to I can come back here to remember what I did and have tried to do so I don't repeat mistakes I have already made.

I find this really interesting actually....and I do like diesels. Please keep up the good work.

OK, so I was standing there looking at my engine bay trying to figure out what I can make to fix the vacuum issue that still exists, but it isn't as big of an issue as it was, it was 10psi vacuum, now it is 1 or 2psi unless I am in first or second and under compression, then it goes to 5 briefly, I am looking at all my vacuum or pressure hoses when I look at the only hose/line that I don't have connected, it's the one that comes from the injection pump that is supposed to be connected to the fitting on the throttle body cover that goes to the air filter from the throttle body in stock configuration, I cannot use that fitting anymore because it is under boost a lot which would try to force the injection pump diaphragm and rack to the idle position.
So I am wondering where to put this line when it dawned on me that if this hose were to go to the air filter itself two things would happen, one is that it would be filtered air going in and out like the stock configuration, and the other thing that occurred to me was that it would actually have a slight vacuum because of the turbocharger sucking air from in there, especially at higher rpms, the dirtier the air filter, the more vacuum, the more it would help pull the diaphragm/rack to a richer position.
So I pulled the propane injection hose off the air filter fitting as the propane is turned off anyway(tank valve is closed), and I connected that injection pump line to the air filter fitting, then I started it up, it ran normal, so I took it for a drive, on the freeway I noticed something right away, the wall I keep harping about was much softer, it doesn't go any faster, but it is a smoother transition, it doesn't get to a certain rpm and fall on its face now, before I used the top third of the pedal and when I came to the wall I had to just put my foot in it to get to higher rpms, now I am using more of the pedal/deeper into the pedal to get to the same rpms, I suspect I would get better freeway fuel mileage if I disconnect this line.
Another thing I noticed was that the EGTs were running a little hotter, it's the first time I have seen it above 1200 degrees since I changed things, but I was floored when it happened, I was trying to get up to top speed on the freeway.
When I returned home I pulled the line off the air filter to see what would happen and noticed an rpm change, at idle the rpms were higher when I disconnected this line, and they lowered when I connected it, I don't know what this means for sure, as I don't have gauges on these lines telling me what it is going on in each line at different rpms.
I am making this up as I go, it runs real good considering what I have done over the last few days, all in all I consider this a positive result so far, wait till you see what I have in mind to fix the vacuum issue, if it works you will likely laugh.
I could likely go faster on the freeway if I didn't have so much stuff stored in the back of the truck, there is a lot of shit back there.

So today I made a valve of sorts, it didn't work as good as I was hoping, it did work, just not as good as the valve I have been using which only works OK.
Here are the valve parts.

Here it is without the spring installed.

Here it is with the spring installed.

Here it is put together.

And here is the tube I mounted it to, I removed the blow off valve and mounted it.

The reason I made this was to test if I could get rid of all the vacuum in the system when I let off the pedal and am under compression in first, second, and third, fourth and fifth are not an issue, I don't know why.
What happened with this valve was that the ping pong ball was just a little to big for the tube it is in, the vacuum from the engine pulled the ball all the way to the "T" and it tried blocking that hole, it is real close top that hole, to close.
It did work though, the moment I pushed on the pedal it went back to where it was supposed to go and allowed the turbocharger to build up 10psi boost, but when I let off, it would build 5psi of vacuum, the valve I have now only has 2 or 3psi vacuum, my goal is for 1psi vacuum.
I have put together another valve using the next size larger fittings, but I didn't have the parts to complete it, I will buy them tomorrow, this one has more room on the sides of the ball to let the air past so the ball doesn't get sucked all the way to the outlet even though it is still close.


This is just a temporary valve, if I can get one to work the way I want it to work, I will make one out of metal tubing and a hollow metal ball, it will also likely be a straight tube instead of a Tee, I just want to see if I can do it.
The truck runs alright now other than the slight vacuum issue, I also need to find the correct speedo drive gear so I can tell how fast I am really driving down the freeway instead of guessing, I might be going over 80mph, but I cannot tell as I normally drive a 521, this 720 is longer and heavier.

So I was looking at what you bought...

You got a really really nice Blow Off Valve.

If you ever think you might get rid of it, I may want to buy it from you...

Or I could make your valve at work out of whatever metal you wanted...


Also, on your valve, could you just put a hard stop for the ball so it doesnt cover the port? Is the spring really necessary then? Probably for that transition from vacuum to boost...

Laecaon » Tue Mar 08, 2016 5:29 am wrote:So I was looking at what you bought...

You got a really really nice Blow Off Valve.

If you ever think you might get rid of it, I may want to buy it from you...

Or I could make your valve at work out of whatever metal you wanted...


Also, on your valve, could you just put a hard stop for the ball so it doesnt cover the port? Is the spring really necessary then? Probably for that transition from vacuum to boost...

Your right Jacob, it works a lot better without the spring, it was either open or closed, the first one worked nice except the ball fit the pipe to tight, about a 16th of an inch gap all the way around the ball, wasn't enough, more air needed to get by.
The second one has not been tested yet, it has slightly more than an 8th inch gap around the ball all the way around.
The reason for the spring was to keep the ball from making it to the side hole, I never thought about making a stop for it, that is a good idea, but I think the spring also plays another function, it keeps the ball from rattling around bouncing off the sides of the tube it is in, it really does rattle violently around in there without a spring.
The one I want to make in the end would just be a straight tube with a hole on each end, one end is the vent, the other end connects to the system, I just don't have the fittings to make that one, I have a lot of tees left over from the fish room I had, just working with what I have.
There has to be something out there that does what I need, but I have not found it yet, the turbocharger guys say I already bought it, but that it doesn't work on diesel engines, they are right, it only sorta works, but it is definitely better than nothing, I just want something that works better.
I did notice something though, when I let off the pedal there is a spike in Vacuum, I am not sure I will be able to remedy this spike unless something opens before it occurs, I have thought about making something that opens mechanically in unison with letting off the pedal, like another smaller throttle body or valve that is connected to the existing throttle body bellcrank, maybe that is the way to go, when I let off the pedal I do decelerate, but if I don't let off that last eighth inch I don't create vacuum either even though I continue to decelerate, but it don't idle properly either in that position, I just need something that works off a vacuum signal.
I wonder if the fitting that operates the waste gate on the compressor side sees vacuum, I never thought about that till just now.

So I made another valve, this one works the best so far, but it also didn't fix the issue, I still have 5psi steady vacuum when under compression while the other valve I paid for only spikes to 5psi vacuum and then drops to maybe 2psi max, but this one held boost real good, I accidentally went over 10psi for a second.
I will try to fine tune it some more, I went to loose already once, and the ball was violently bouncing around in the tube, this time it stayed closed at an idle.
I also fueled it up today and had a couple guys come over and ask what I had in it, we talked for maybe 10 minutes and they were amazed how well it ran.
When I mentioned the vacuum issue and the oil in the system, they told me all diesels did that, so maybe I am over reacting about this oil thing and have it good enough now.
I can say this, I was very happy that this valve doesn't make a hissing sound because this one isn't blowing off after 6psi like the one I bought does, I will work on it some more, this time it seemed predictable, as you can see it is a straight one, but it is harder to adjust.




I should have taken a photo of it installed, I will tomorrow.

So after making that slight modification last night I installed it this morning and went to the wrecking yard to look at brake booster check valves, I brought 3 different types home, I will make a plate and install them to see if any will work better than what I made.
Fact is this last one works great so far, on the way to the wrecking yard I had to keep letting off the pedal because I was going over 10psi boost, on the way home I adjusted the waste gate and did it perfect the first time, if I floor the pedal it creeps up to 10psi and goes no farther now, but when I let off it still gets to 4psi vacuum, but it is quiet the way it is now, so I will start to fine tune what I have made now, what I am trying to do is not have the ball open at an idle, but open during any other higher vacuum situation, I will loosen the valve a sixteenth inch at a time now until I get where I want, or till I go to far, then I will add a washer, this one works good so far.
I don't like hearing the boost blow off, and now that the waste gate is functioning I don't have to hear it anymore, so this is better than that $200.00 valve I bought.
Here is the valve installed.

I need a yellow speedo gear now to make my speedometer show the correct speed and mileage, here is a photo about what I am talking about.

YELLOW is the 16 tooth for the 3.36
BLACK is the 17 tooth for the 3.54
BLUE is the 18 tooth for the 3.70
WHITE is the 19 tooth for the 3.90
RED is the 20 tooth for the 4.11
PURPLE is the 21 tooth for the 4.38
This is what the Zcar.com said above, so either they are wrong, or the gears in the photo are marked wrong, right now I believe I need a yellow gear.
Well I guess I don't know which size I need now, I thought they were all the same, I will have to pull the speedo cog Friday, I am working tomorrow.

So all that fighting trying to get the damned thing to start and shut off with the key was the freaking oil pressure switch, the freaking switch that works the oil light, no oil pressure the thing will not start.
I sold a DPC module a couple days ago to a guy that knows electronics, he was saying that his points were fried in his, and when we put one of mine in it worked great again, so while talking to the guy I told him that my other engine overheated one night and ruined it just because my dash lights didn't work that night as we were talking about white smoke and the causes(mine overheated), he then said that the oil pressure is wired in to the DPC module but the water temp was not even though it has the wires.
So I had been thinking about that, and I decided to hook everything up to the injection pump and disconnect that oil sensor wire to see if it would start and shut off, and it now works great.
But now I have another thought, if the light did work but it took a few seconds after it was running to go out, then do I have low oil pressure, or is it just a finicky switch/sensor, now I need a oil pressure gauge to know if the engine is just wore out, or if the switch is going bad.
This was driving me crazy at one point, now after making all them little mount parts and putting the shut down cable in, I don't need it anymore, but it is funny to watch the knob move all by itself in and out now, I can see it move to the start, then run position, and when I turn it off it pops out at me like I was pulling on it.

Always fun to see what you come up with man. And honestly, you have to be the only person I know with a turbo that hates the sound of boost being let off lol