need advice with diagnosis - engine failure
 

A little history first. Purchased my '83 SD a few years back. 310K miles on a broken odometer. No real idea how many miles on car. Always smoked some on start up and engine shakes at idle. However it has always run really well and uses no oil. Now for the problem. A few weeks ago she was purring along and suddenly developed a pronounced clatter in the engine compartment. Ran poorly also - like it was not firing on all cylinders. I had my wife and grandson in the car so I just limped it on home and parked it. A couple of days later I had time to start it up and see if I could identify the problem. It fired right up and ran smoothly. Drove it to town and after about 30 minutes of driving, the problem showed up again. I think the clatter was coming from the left side (injector pump?). When I got home I popped the hood, but she was purring smoothly again by that time. :confused: I knew I had better call in more competent help for this one, so I drove it to a local diesel mechanic for a diagnosis. He didn't have time to investigate at that moment, so I made an appointment for later in the week. On the way home I heard the dreaded clatter again (seemed to be a rythymic double clatter). By the time I neared my driveway the engine died completely and the car did a bit of a nose dive. Kinda like the engine reversed itself. I hit the key and it started again, ran a few seconds, and did the die / nosedive thing again. I coasted into my drive (thank the Lord) and tried once again to start it. Engine would not turn over (battery is good). I pulled it to my garage with the tractor and waited a couple of days. Tried to start it again and the engine turned freely and sort of tried to run on a few (not all) cylinders. :confused::( Although I intend to trailer it to the mechanic before too long, I would like to have some idea what to expect. Given that long story, do any of you seasoned MB folks have any good advice?

What was the oil level when all of this was happening?

that's a tough one since it's probably a mechanical failure with the IP or the chain (i'm thinking something with the chain drive of the IP or possibly just a failing timing chain tensioner) and these kind of issues don't come up very often on that engine. your engine could have very high (500K+) mileage and the IP is just done for or it could just be the tensioner. maybe someone with knowledge of very high mileage OM617's can chime in to verify. in the meantime i would not try to start it again since the timing chain might break (if it breaks the engine is pretty much toast). hope someone with more knowledge can chime in

Answer
 

I am seriously concerned from your description.

Pull the valve cover.
Crank the engine around until the camshaft timing mark is aligned.
Now take pictures of the harmonic balancer, we need to see the timing numbers.

If the base timing is good, it may be a bad timing device, fuel or fuel system issue.


For the moment the possible list is to large.
Brief Example:

* Extreme bad fuel and/or infestation.

* The vacuum pump came apart, dropping pieces between the chain and crankshaft sprocket?

* The timing chain tensioner failed, allowing the chain to skip teeth - loose timing?

* Broken valve guides?

* Failed - damaged timing device?

* Head gasket failure?

.

Some good advice as always from Roy. If you've never done the timing chain stretch measurement, here is a link to the DIY article.

Begin with step 10 of the DIY. Align the #1 lobe as shown, so the notch on the cam tower and timing chain are aligned. Then take a photo of the harmonic balancer.

Here are the pertinent photos from the DIY, so you know what to photograph.

http://www.peachparts.com/diy/om617t...ain/cs_10a.jpg

http://www.peachparts.com/diy/om617t...ain/cs_10b.jpg

Many thanks for the good advice. I will follow through and report my findings soon. Always appreciative for to generous help of the forum members. If the engine is history, my two '83s will merge into one fine car.:)

Hey John,
Sad to hear of your trouble.
I think Roy has given you some good leads.
Getting the rocker cover off is a worthwhile exercise before going any deeper.
The clatter going away & then returning may be a worry to some. Makes me think its not totaled.
Depending on the noise, it could be a fuel delivery problem (IP, timing device).
I definitely agree you should not run it again until the timing chain & cam are checked.
Good Luck !!!!!

Hey John - sorry to hear about your woes. If there is anything I can do to help, let me know. My F250 was going through about the same thing last week. It is a completetly different animal though. The daggone electrical fuel pump was intermittantly getting power and is now running fine.

Again - let me know if you need help.

I'm slowly checking this thing out. Pretty soon I will have a bit more free time to follow all the good advice (and learn a bit in the process). I removed the valve cover and don't see any obvious damage. In the past I have performed several valve adjustments and, best I can recall, turned the crank by wrenching on the power steering pump nut. I gently tried that last night but it did not move freely. Rather than trust my memory and put a little more muscle into it, I will reread the thread on turning the engine by hand. Then will follow the good advice and get lined up and snap photos. Also, I have to learn how to reduce the size of the photos to get them onto this forum. Boy, do I have a lot to learn. :D Thank goodness for spare cars and helpful forum members.

Hey John if you want to turn that engine the best way is with a 22mm or a 15/16 deep socket in the center of the front hub is really the way to go, especially with a 1/2 ratchet and a piece of pipe for a cheater. Don't push to hard, if it is stuck you will just break more stuff.

um, that's 27mm, or 1-1/16" socket with an extension.:D

This sounds very much like how my '83 300sd, which fits the description of yours very well actually, behaved many years back -- though it never got to the nosedive stage, only horrible sounds as you described.

I tried to limp home but lost my nerve and had it towed. In my case I had had enough of the car at that point, it had numerous other issues, and I called a friend who wanted it. (I simply assumed the behaviour was a major engine mechanical failure.)

He listened to it further and diagnosed the noise as coming from the injection pump. He installed a rebuilt pump and the car runs and drives today. He is trying to sell it back to me, actually.

So hang in there.

One thing to look at, might be the A/C compressor clutch. I had something similar happen once and had to cut the A/C belt to get car home. Turned out teh clutch and compressor had seized up. In the end, the engine would not turn at all.

Your problem could of course be entirely different.

Thanks so much, probably today I'll try to further diagnose. Just had new AC compressor installed, but will looking into failure in that dept.