Builds LJ78 Build: "The Space Whale" (1 Viewer)

[gannex]

made a little more progress today...

• head is on
• some of the wiring done
• timing kit installed
• intake manifold re-installed

I suppose I should've painted the rear timing belt cover, but I guess I'll get to that next time I change the timing belt!

I'm still not sure whether the obstruction was due to the glowplug piece (which I never did find) or the poorly seating valves, but the engine seems to crank around nicely now!

 

[gannex]

@GTSSportCoupe

I'm almost finished!
I just have two quick questions:

Any idea what this bracket is for? I can't remember where it came from.

Unfortunately the gasket kit I got from 4wheelauto doesn't seem to have a gasket for the top part of the throttle body. It just came with this paper one, which seems to go between the intake manifold and the throttle body, but I already have a metal one for that, so I'm using that instead. For the time being, I'm just going to make a paper gasket for this spot.

As you can see, the second valve in the throttle body has been removed by the previous owner. This valve is associated with the EGR, right? The way it's set up now, this means air can just flow through into the intake even when the main throttle body valve is closed. Should I leave it like this, or should I block off the smaller hole?

 

[gannex]

So it turns out a small part of the glowplug casing that was stuck in the hole for cylinder #2 was still there even after all this!!! I definitely should've test-installed the glowplugs before putting the cylinder head back on. Anyways, calamity was narrowly avoided as we were able to get it out with one of those tapered, square screw extractors.

For the first time ever, all 4 functional glowplugs are installed (as well as 4 correctly spraying injectors)!

Almost there!

 

[AirheadNut]

Looking great! While you’re in there I would strongly recommend drilling out the two little screws that hold in the large butterfly valve in the intake and removing that as well. Without an EGR system it’s redundant and your engine will perform better without it.

 

[gannex]

Looking great! While you’re in there I would strongly recommend drilling out the two little screws that hold in the large butterfly valve in the intake and removing that as well. Without an EGR system it’s redundant and your engine will perform better without it.

OK so neither butterfly valve is important at all?

 

[AirheadNut]

Nope. They’re just intake restrictions at anything but WOT. Just make sure you don’t mess up the TPS.

 

[gannex]

@GTSSportCoupe @AirheadNut
Hey guys, so I've got everything hooked up and I've been trying to start it up. I don't think the glowplugs are coming on for very long, so I've just been hardwiring them for 8 seconds or so and trying to start up. It almost got going once, but it won't start. I'm wondering if the fuel pump might be the problem. I tested the plug on the top of the fuel pump and there doesn't seem to be any signal. When I disconnect the injectors and turn it over, fuel spews out of the lines, but it doesn't seem to be under very high pressure. Should I be seeing a great mist of fuel coming straight out from the lines of I turn it over with the injectors disconnected?

 

[coldtaco]

Careful with direct glowing your glow plugs, it doesn’t take much 12V to burn them up. 8 seconds might be enough to burn them up. Maybe timing somewhere is off?

 

[Dprio34]

Probably the fuel lines just not bled. Just loosen all 4 lines and crank starter, until you see fuel coming out. As fuel comes out of each line, tighten the respective line up. Loosen, not disconnect, or otherwise, yes, fuel be spraying everywhere. That would be an unnecessary mess.

 

[gannex]

Careful with direct glowing your glow plugs, it doesn’t take much 12V to burn them up. 8 seconds might be enough to burn them up. Maybe timing somewhere is off?

Glowplugs are fine.

I'm pretty sure I did the timing correctly. I didn't adjust the timing of the fuel pump though, because I don't have the tools, but it should still run if it is close to correct, right? My plan was to get it running and then drive it to a diesel shop to do the precise timing adjustments

Probably the fuel lines just not bleed. Just loosen all 4 lines and crank starter, until you see fuel coming out. As fuel comes out of each line, tighten the respective line up. Loosen, not disconnect, or otherwise, yes, fuel be spraying everywhere. That would be an unnecessary mess.

I primed the hell out of it and turned it over until diesel seeped out of the fuel lines before tightening their connections to the injectors. Is this correct? I made sure quite a lot of diesel spewed out before tightening the nuts.

One thing is, it doesn't seem like a high pressure of diesel is pumped out of the fuel lines when I turn it over with the lines disconnected. Could it be that there is an issue with the electrical connections to the pump?

 

[Dprio34]

If you totally loosened the lines, it would be spraying all over the place, yes. If you just cracked them loose, probably just a trickle of diesel coming out.

Just to confirm, you bled all 4 lines? Not just 1 or 2 of the 4 lines?

You have the injection pump aligned correctly? There is an alignment mark on the outer ear.

 

[gannex]

If you totally loosened the lines, it would be spraying all over the place, yes. If you just cracked them loose, probably just a trickle of diesel coming out.

Just to confirm, you bled all 4 lines? Not just 1 or 2 of the 4 lines?

I did bleed all 4 lines.
If totally open then, it does not spray all over the place. Quite a large volume of fuel comes out, and it looks like it comes with the correct timing, but it does not seem to be under very high pressure. I've seen some YouTube videos where they turn it over with the lines completely disconnected, and a huge jet of diesel most sprays out. I don't seem to be getting that. I also don't see any signal from the plug on the top of the fuel pump. Could it be that the pump is being run purely off the timing belt and not getting any electrical power st all, so it's not pressurizing the fuel?

 

[Dprio34]

ok, you bled all the lines,
did you turn the crank pulley by hand several times / rotations prior to cranking the motor with the starter?
just ensure the marks on the injection pump and timing case are aligned as well.

this pic is out of spec.

 

[gannex]

ok, you bled all the lines,
did you turn the crank pulley by hand several times / rotations prior to cranking the motor with the starter?
just ensure the marks on the injection pump and timing case are aligned as well.

this pic is out of spec.

View attachment 2702110

I just figured this out. I thought it was just the timing marks on the cog that mattered. I didn't know about the marks on the injection pump/timing belt housing. My pump was retarded. I've adjusted it correctly now.

I also tried bleeding the return line via the banjo bolt on top of the pump. Unfortunately, I over tightened the bolt that goes in the top and broke it, so the project is dead in the water until I get that bolt.

 

[gannex]

ok, you bled all the lines,
did you turn the crank pulley by hand several times / rotations prior to cranking the motor with the starter?
just ensure the marks on the injection pump and timing case are aligned as well.

When I did the timing belt, I cranked it by hand 4 times and all the cogs lined up with their marks.

 

[GTSSportCoupe]

@gannex ; sorry I did not reply earlier. Was tied up all weekend with work/family. I see you've had some good advice above in the meantime anyhow. Where are things at right now with your engine?

When the fuel delivery lines have been off, it can take quite a bit to get things going again. I've done this a few times on mine over the years, and have never disconnected the fuel lines from the injectors to get the fuel moving again. So I can't really comment on how much fuel sprays out, or how the pressure looks etc. I would not expect much pressure, as there is no resistance of course. An open pipe won't have much pressure.

What I usually do is push the fuel primer pump for what seems an eternity until it gets hard. After that I crank the engine quite a lot before it starts to catch. Be sure to 'rest' the starter in-between tries to keep it from overheating. Also, keep the accelerator pedal MASHED while cranking. This helps move more fuel through the lines and push out the air faster.

If none of that works, try checking the connector at the spill valve. Remember, it is a solenoid that is PULSED, not on constantly like a mechanical diesel would be. So you can't measure voltage there with a regular voltmeter. The best way to check it is test the resistance. Also, be sure the wiring to it has not been damaged.

You can check the codes from your ECU to see if it is detecting any issues as well. This might identify other things that could be contributing to a real problem.

 

[gannex]

I finally got the part made. It was a little difficult to find a metric bolt with such a fine thread, and the head is a different size, but this one seems to fit well and depresses the spring.

@gannex ; sorry I did not reply earlier. Was tied up all weekend with work/family. I see you've had some good advice above in the meantime anyhow. Where are things at right now with your engine?

When the fuel delivery lines have been off, it can take quite a bit to get things going again. I've done this a few times on mine over the years, and have never disconnected the fuel lines from the injectors to get the fuel moving again. So I can't really comment on how much fuel sprays out, or how the pressure looks etc. I would not expect much pressure, as there is no resistance of course. An open pipe won't have much pressure.

What I usually do is push the fuel primer pump for what seems an eternity until it gets hard. After that I crank the engine quite a lot before it starts to catch. Be sure to 'rest' the starter in-between tries to keep it from overheating. Also, keep the accelerator pedal MASHED while cranking. This helps move more fuel through the lines and push out the air faster.

If none of that works, try checking the connector at the spill valve. Remember, it is a solenoid that is PULSED, not on constantly like a mechanical diesel would be. So you can't measure voltage there with a regular voltmeter. The best way to check it is test the resistance. Also, be sure the wiring to it has not been damaged.

You can check the codes from your ECU to see if it is detecting any issues as well. This might identify other things that could be contributing to a real problem.

Hi @GTSSportCoupe!
No problem!

I think I was having two problems last week: The timing degree of the diesel pump (as @Dprio34 pointed out!) and incompletely bled fuel lines.
I am going to start by priming the hell out of the pump and then draining from the banjo bolt I broke last time, then I'll bleed the fuel lines themselves, one at a time, and with the accelerator mashed, as you pointed out.

 

[gannex]

OK so I got the new bolt on and bled the return line, but I've ran into a new issue.

As instructed here

ok, you bled all the lines,
did you turn the crank pulley by hand several times / rotations prior to cranking the motor with the starter?
just ensure the marks on the injection pump and timing case are aligned as well.

this pic is out of spec.

I clocked the timing pump after my last attempt to start it up (before I broke the fuel return line bolt). Before that, I had the mark on the pump slightly below the mark on the timing belt housing, so I undid the three bolts and rotated the pump clockwise to line it up with the mark. Before doing this, I recall that fuel was coming out of all 4 fuel lines when I tried to bleed the lines the first time. As I cranked the engine, I would see fuel come out in the order 1-3-2-4, but now fuel is only coming out of lines 1 and 2, and it seems like it comes out at the same time. No fuel (or very little fuel) comes out of lines 3 and 4 at all. Needless to say, the engine wouldn't start.

This seems like something timing-related. I am sure fuel was coming out of all 4 lines before I rotated the pump. I took the fan off and double checked that the timing marks on the pump/crank/cam sprockets are lining up correctly and they seem to be fine. No idea what I did.

 

[Dprio34]

@gannex , with all 4 fuel lines loose, how many times did you crank the starter to get them to bleed? I would try it again, with all 4 fuel lines loosened until you get fuel coming out of all four lines. 10-15 cranking attempts may be Necessar.y. Make sure to give the starter a rest between 2-3 attempts. I think you are almost there.

 

[gannex]

@gannex , with all 4 fuel lines loose, how many times did you crank the starter to get them to bleed? I would try it again, with all 4 fuel lines loosened until you get fuel coming out of all four lines. 10-15 cranking attempts may be Necessar.y. Make sure to give the starter a rest between 2-3 attempts. I think you are almost there.

Hmm. I cranked for about 10 seconds at least 10 times. I think there may be a little girl coming from line 3, but line 4 still has nothing.