603, won't start, horrible squeaking noise
 

The SDL died while my wife was driving it. She was slowing to a stop sign when it quit running and would not start. We towed it home, and it would only crank very very slowly, not enough to get going. There is smoke coming out the tailpipe when cranking. Inside the car I could hear a faint squeaky noise. When I stood outside and she cranked it it was ear piercing.

I took the serpentine belt off, hoping that it was a siezed alternator or AC compressor. No such luck. It still cranks really slow, but the squeak is not as loud as it was in december.

I know I have to take it apart and find out what is going on, what I want to know is where to start. My plan is to just start at the top and go down. Valve cover, head if needed, and keep going till I find something.

Does anyone have a better plan? any guesses as to what/where I should look for? 240,000 on the car, no signs of anything wrong till it quit.

any help appreciated. -Andy

Did your wife notice if it had lost oil pressure, either a drop in the gauge, or a red light?

For the heck of it, I'll suggest that you check the oil level, since one possibility is an oil leak, un-noticed, with resulting loss of oil pressure :( followed by dry or seized bearings. Siezed bearings could account for really slow cranking with an othewise good battery and starter, produce an ear-piercing squeaky noise while cranking. :eek:

BTW, I hope you can eliminate this nasty possibility... :rolleyes:

Does the engine still have the original Vac pump? The cover on the old style was crimped on while new ones have four torx head bolts on it. Bad vac pumps have probably destroyed more 603's than the cracked #14 heads I think! At least a cracked head is not in itself a complete disaster unless you let it go too far maybe.
The first thing to remove is the vac pump. If its ok, no little bits and pieces falling all over the ground, then I'd start looking at the timing gear, and that means the both manifolds and then the head can come off (be aware of the proper sequence for loosening head bolts!)
I don't envy you, I just tore down the top end of the engine in my '87 300D last Fall. I did not have to remove the front timing cover, as there were no problems with it turning over (it had a cracked head!:eek: )
I saw a bad vac pump and what it did! it locked the engine up AFTER the owner's daughter drove it several (many?) miles while it was making a loud clicking noise. No squealing, just clicking then Kraby Kaputskie, the ball bearings jammed the IP timing ramp and the the vac pump cracked up in parts and the engine locked up because the timing chain was held frozen. Your sounds like it may be a spun bearing though hard to tell at this point.

Oh my that sounds like a vac pump. Before pulling anything else apart remove the vac pump and inspect it. They come right off, hopefully yours is still fine.

If it was the vac pump and the engine still turns over you got real lucky. That means the timing chain didn't snap so no valve job. But you are probably still going to have to pull the head to get the front cover off. All those rails will need to be inspected or replaced.

Seems we have a rash of 603's loosing oil pumps :confused:

well......the last one I fixed did.


.

I put in a new vac pump 18 months ago, so I doubt that is the trouble, but I will start with checking it.
I did not have any oil pressure or loss issues, but I will check the oil level too. thanks for the suggestions. -Andy

Just for information........can you put a 27mm socket on the crankshaft bolt and attempt to rotate the engine by hand?

You should just be able to turn it with some muscle on a 1/2" ratchet wrench.

You should easily be able to turn it with a 18" breaker bar.

This would provide some insight as to whether the engine is free to rotate............or not.:(

Well of the vac pump is recent then you can probably rule that out. I'd still check it, simple enough and would rule one thing out.

I'd try and turn it over by hand like Brian suggested.

I will check the vac pump, then pull the injectors and try to turn it. Is it correct to assume that if it is a bearing it will give even resistance as I try to turn it? -Andy

Well bearings just don't go bad all of a sudden. There would have to have been a sudden lose of oil pressure.


With the injectors out and an 18in breaker bar they turn over pretty easy for a 6 cylinder diesel.

If there is an internal engine problem causing the starter motor to slow down dramatically, you'll never turn it by hand.

I can turn my engine over by hand with a wrench on the power steering pump pulley nut. Easier to reach than the crankshaft.

then I would focus on the starter.
 

good luck!

Actually, wheelguru (thread originator) has not yet said whether he can turn the engine by hand...

We do wish wheelguru the best of luck too, of course... ;)

No offense but their are very large bold letters in the FSM that say don't do that.