Shredded serp belt, ext lifters damaged but good compression

Shredded serp belt caused timing jump. I am hoping to replace lifters and get the golf running again but cannot locate 2011 tdi cjaa lifters...any ideas??

peaceodarock said:

Shredded serp belt caused timing jump. I am hoping to replace lifters and get the golf running again but cannot locate 2011 tdi cjaa lifters...any ideas??

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I am an EXPERT in this topic. First what happened? So the serp belt (alternator) jammed up the timing cog belt (cams/water pump/HPFP) by getting under timing belt cover? right?

OK one thing at a time. If you can un-jam the timing belt and rotate engine with socket on crank, care not to force anything, can you get timing marks to line up? Remove the timing belt. Install the new belt with timing marks aligned. Don't worry about idler bearing or water pump for now. Can you turn the engine over by hand with socket wrench on crank shaft? Again don't force it. Are the timing marks aligned? If not reset the belt. Next do compression test. Leak down testing is best. If the compression test good on all 4 cylinders, try and start it. If it runs you lucked out. You can go back and change the water pump and idler bearing and call it a new belt job. If you are not getting compression leak down can tell you if it is the exhaust or intake side (by hearing air leak out). So now to fix.....

Valve can hit the piston causing valve damage (bending), piston damage (marks), lifter damage and CAM damage. The lobes on the hollow cam shaft are pressed on, and they can get twisted out of alignment on the cam shaft.

One "simple" fix or at least straight forward, is find a used engine in a salvage yard, install that and part out the original engine. That worked well for me.

The fix? Take the head off and inspect and replace parts as needed. You may or may not be able to see witness mark of valve hitting top pf piston. The piston top and valve faces are parallel, hit flat face to face, not at angle. However part of valve would be unsupported as the piston has a cup in middle. The valve contact may leave mark in the soot on piston top. However I noticed that normal combustion leaves a light outline of the valve from normal combustion patterns. Hard to tell if they hit, but if there is metal moved in piston (dent) than they hit.

If you did damage, it may be (likely) to only one jug. Once timing slips engine stops when a cylinder piston valve hit... That is why it is critical you don't try and crank it over. So it's not like you will all new valves and lifters. It is so hard to tell until you take it apart. Again remember cam lobes can rotate on the cam shaft since it's not made as a one piece.

The bottom end and piston should be OK even if piston touched valve. If you moved metal on the piston you may be able to blend a small dent out? I doubt you are going to hurt the stout rods and bottom end.

Mine stopped at idle and did no damage. The dealer said engine was bad. I replaced the engine on my own with almost new salvaged engine. Once I had original engine out I realized they were wrong, the engine was fine. Compression was good. I pulled head and sent it to shop. It was fine. I had to "work it out" with VW and dealer. I ended up coming out whole. Have a 2013 engine in my 2010 with 50K less miles than the car.

Jumped timing means you have to pull the head to inspect for collateral damage. Shattered lifters just verify that recommendation. If you have valve to piston contact hard enough to shatter lifters, you may have bent connecting rods and have valves that will fail even if you can get the engine to run smoothly right now.

TDI valves are straight up and down instead of angles like a gasser and impact damage will cause a stress point that will cause the valve head to drop off a few thousand miles later even though the engine seems to run just fine now.