I pulled the engine from my 1983-300D after the timing chain broke at 60MPH, braking the cam in four places and two of the cam towers. The good news is that when I partialy disassembled the engine I found that the pistons are OK. I found some white ash like deposit on the number 5 injector "nipple" on the bottom of the head. Any idea what caused that? Is that the prechamber? Also number 1and5 pistons where carboned up. I'm planning on disassembling the head this week and also pull some of the bearings and check them. All help apreciated.

Make sure none of the valves were bent when the chain broke. Bill Lewallen Lex. Ky.

The "nipple" you see protruding from the head is indeed the pre-chamber. The ends will usually have a greyish color, which is normal.The pistons will have carbon deposits on the tops because of the burning of the diesel fuel. If I can be of more help, let me know. Bill Lewallen Lex. Ky.

Thank you Bill. I will be disassembling the head to check every valve.