When my son was driving from Tucson to Phoenix last weekend, he heard a loud clunk followed by a quick rise in engine temperature and unusual noises. He immediately pulled over and turned off the ignition. When the engine did not shut down, he raised the hood and used the manual shut off.

Attached is a photo of what he saw. The vehicle was towed to a repair shop. After removing the valve cover, they discovered the following:

1. The upper timing chain nylon guide rail was broken and parts of it had apparently lodged under the chain and bent the guide rail attach bolt.
2. The chain had skipped three links although there is no apparent damage to the camshaft or supports.
3. The exhaust valves each measured .018 (loose) but the intake valves indicated normal clearance.
4. The car did not "boil over" and there was plenty of oil showing on the dipstick.

The timing chain did not break. What caused the chain to break through the valve cover is still a mystery, although the timing chain tensioner is suspect. The timing chain and tensioner were replaced about 3 years ago.

If anyone has seen this happen before on a diesel and has clues as to the cause, your input will be appreciated. The car has @240K miles, uses no oil, and is well maintained.

Thanks in advance for your help!

Larry Campbell
1981 300SD (240K)
1979 300SD (325K)
1982 Chevy 1/2 ton P/U 6.2L diesel (202K)

Attached Files

HPIM0791.zip (55.2 KB, 204 views)

could you upload the pic to like photobucket.com or something i dont trust downloading files at all offline

Here's the pic.
People with macs have little to fear.

All I can say man is wow. Can't imagine what would have happened if the chain had broken.

Attached Thumbnails

 

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'84 190d 2.2 - Silver
Converted to 5-Speed
'84 190d 2.2 - Blue
Factory 5-Speed

'76 300D (W115)
Sold, found again in less auspicious circumstances

OW. That looks painful.
Since it still ran after the event, you should be able to save it.

Not exactly the same thing, but this is my saga from a few weeks ago:

Stuck in NE - vacuum pump failed

My friends '85 380SE gasser did the same thing when a chain rail broke. I think that a piece of the chain rail gets between the cam sprocket and chain and doesn't clear the inside of the valve cover as it rotates around. I consider you VERY lucky. My friends 380 skipped more than 3 teeth, took out alot of valves and a piston. To say the least, his wouldn't restart
You WILL have to pull the head and surely replace valves but the fact that it still ran leads me to think that the engine is fully salvageable. Diesel pistons are increadably TOUGH.

In looking at the previous thread where He lost his vacuum pump, With what YOUR car suffered, I would definately check the vacuum pump also.

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My Truck.. 2007 DODGE, 5.9 Cummins, 6spd stick, 4X4. My car..1977 240D, OTHER WHEELS...1955 VW Oval window bug, European Delivery (Holland) with a 1700cc, 2 barrel, Porsche drum brakes. 1939 WILLYS Pick-up. 1967 Triumph 200cc Tiger Cub. 1976 Honda 550F 4cyl Motor Cycle.