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Need a diesel expert please - LD28 motor

Deuce

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I am building a truck with an LD28 motor and am not super techy with diesels. It will not start when cold without a good glow and a shot of engine start. Starts fine when warm.
Needs a really high idle until up to temp. Then it is fine.
I think the sump is overfilling with diesel thining the oil. But maybe that's because it has been attempted started a dozen times. And actual started about half dozen over the last year.
Without draining I won't know, but my guess on the dipstick is at least a litre up.
Seems to take forever to warm up. But heard that is normal for diesel engines.

Currently it does not have an air filter.
No vacuum lines to/from the auto trans (jatco 4n71b).
And radiator / water in cooling system doesn't make any difference except that I can run it for longer.

Build thread on page with the first drive.

My thoughts are either:
- Leaking injector(s)
- bad cylinder (s) and low on comp.
Although I don't think it sounds funny, and it drives fine / starts fine when warm.
Approx 1985 engine.

Any thoughts or discussion appreciated.
 

Heavy VT

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Put the fuel return line in a bucket with a little diesel. See if it is blowing bubbles when running. If you have bubbles there is an air leak somewhere. Also the front pump seal and shaft could be worn causing a fuel leak into the sump.
This seal can stop leaking when the shaft gets hot and expands. Stopping the leak when hot.
 

Deuce

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Put the fuel return line in a bucket with a little diesel. See if it is blowing bubbles when running. If you have bubbles there is an air leak somewhere. Also the front pump seal and shaft could be worn causing a fuel leak into the sump.
This seal can stop leaking when the shaft gets hot and expands. Stopping the leak when hot.
Thank you.
That gives me 2 things to look out for.
I'll see what comes of it all after some more testing.
 

shane_3800

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First thing would be to comp test it, if it does have a leaky injector all sorts of bad things can happen.
So do a comp test which you'll probably need to hire a diesel on from mechanics tool hire.
Then if that's good do the checks as above.

If it's smokey when driving under load the injectors could be stuffed to check this put it under high load at moderate RPM like a big hill. If it's like a steam train it's getting way to much diesel and is likely worn injectors.

Also I can't remeber if the injector pump on these is chain or belt drive? But it should have adjustment like a dizzy. If the timing is out it will be hard to start.

If it is overfueling it can cause damage to pistons and heads.
 
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