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Engine Specific Info and Questions => IDI Engine => Topic started by: boxer246 on March 10, 2008, 05:42:29 pm
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Ok so I finally got my freshly rebuilt 1.6TD into my Caddy hoping for a nice improvement over the NA. When I finally got it started, which took forever, it only wanted to run on like 1/2 to full throttle. Lots of black smoke, and hardly any power. Of course I only took it around the block because I dont have a downpipe on it yet and had the hood off....but it was a turd.
Some details about the motor before it was taken apart and rebuilt:
It was sitting for ten years and had no compression....totally wore out. When I got the engine running the thing wanted to run-away, so I had to shut it down...I tried it several times, always the same thing....seemed like a sticky injection pump. I figured...no big deal, its gonna be taken apart anyway.
Some details about the rebuild:
All new everything, of course. ist oversize pistons, new valves, valve job, resealed turbo, injection pump cleaned, checked and re-sealed. Timing checked, double checked triple checked, pump timing set to 1.00mm with proper tools, new injector nozzles.
At first thought, it kindof seems like I got the throttle lever off one notch. But before i took it apart, I drew a picture, and marked the shaft and lever and put it back exactly as it was, so that is unlikely, unless it was a tooth off before I got my hands on it. I suppose its possible the pump needs a new feed pump and rotor and head....it does have some mileage on it and I imagine the internals are original. When I resealed the pump it looked good, there was no obvious wear. I havent checked the internal pump pressure....I need to make a setup for that yet.
Tomorrow I will run it some more, see if I can figure anything else out. Maybe re-clock the throttle lever on the shaft....who knows.
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did you just throw new nozzles in the old injector bodies or did you have them pop tested?
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No I did not pop test them. And at some point maybe I should. But I really do not think thats whats causing this problem.
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well if they are all opening at different pressures then it is throwing off the timing of each individual cylinder and will certainly cause lots of black smoke, which we all know is unburnt fuel, or wasted power
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have you re-checked compression after rebuild? might not be a bad idea. too much black smoke can be bad compression as well... but usually the compression needs to be really really bad to do that.
any head work done?
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Yeah new valves, guides, valve job, re-shimmed,
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Over on another diesel forum i ran across some comments about a pump being 180 deg out of time (happening during a rebuild). I guess this can happen if one doesn't mark the indexing between the drive shaft and the camplate in the IP? I never even thought about it.....you know one of those critical little details!!!
Could this maybe be my problem? Should the motor even run at all if the IP is timed 180deg out?
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Yeah new valves, guides, valve job, re-shimmed,
oops missed that in your orig post... and about the 180 deg out, it is possible.. never experienced it personally but from what others say, it will run, but run like shiite.
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So i went out and turned the IP sprocket 180 deg and that fixed the problem. But now the thing seems like it doesn't want to do anything from idle to half throttle. Like theres nothing there. I was very careful during IP disassembly to mark and take notes on the throttle arm to shaft positioning but it runs like its off one tooth.
At least now there's no smoke, (at least until I get on it) and seems to run right.
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You probably need to move the arm on the throttle shaft then. Or did you remove the fuel screw? It might not be in the right place as well. If so, you might try adjusting it a little at a time first, and see if that makes a difference.
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Yeah I'm probably gonna try to move the throttle lever on the shaft and see what that does. Damn I hate fighting with those throttle arm springs!
I did not remove the fuel screw. In fact, it is still wired in place with the lead anti-tamper seal from the factory or prior rebuild shop. Anyways, doesn't this screw only affect the total throttle control of the fuel collar at full throttle only? I dont think it would affect idle to part throttle at all. Maybe i'm totally off on that though.
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yes that was me on Jack's forum Andrew...figured i would post both places to get some more ideas.
Jimfoo....you were right...I needed to adjust the max fuel screw. I still have some fiddling to do as it is blowing a bit too much smoke at higher revs, but since this is a fresh engine I am being ginger with it so I cant accurately judge top end power and smoke yet. I seem to have it where it doesnt hang up on the revs after I let off the throttle, yet it idles decent.
Andrew, yeah I was thinking about if I had the aneroid lever on the wrong side of the control lever....wasnt sure if that was physically possible. I guess I can take the top off the diaphragm and look down and see what the pin does vs. what position the throttle arm is.
At least I'm pretty confident the throttle lever is located properly on the throttle shaft.
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If it's blowing too much at higher revs, try turning the boost pin to a less aggressive part of the slope.