Hard stop when the engine is rotated by hand, I need some advice.

Several of you know that my daughters 01 Bug quit while she was driving. It restarted and sounded terrible. After troubleshooting I found the engine was in time and the turbo seemed good. I found the clutch had broken. The pics and story are here.

http://forums.tdiclub.com/showthread.php?t=506276

I got it all back together rechecked the timing and started it. It still sounds terrible. I began troubleshooting again. IQ, jumping around, cylinders at -1.88 or + 1.88 at the limit. Random misfire codes.

I checked the timing, it’s right against the upper line. I finally got the IQ around 4.5 but it is not steady. I checked for injector leaks, none. I swapped out a couple of injectors, they made no difference in either cylinder. I checked the #3 cylinder wiring and one of the injectors I swapped was the #3.

I shut it off rotated the engine to check the timing again and now I have a hard stop. So I loosened the belt, removed the cam to check the lifters smooth and shiny, some wear but no domes or spider cracks. The last three lobes of the cam closest to the vacuum pump show some chamfer wear so a new cam should probably be considered.

I reassembled and reset everything to TDC rotating the crank 1/2 a turn to lower the pistons and moved the cam and pump then I locked them and put the crank back to TDC also. After all this I tried turning the engine by hand and it still is up against a hard stop.

Have I forgotten something or do I have a valve in a cylinder? Before I pulled the head I thought I would ask and see if anyone had a similar experience. If I have a valve in a cylinder how did that happen when I have no evidence of valve piston contact in the cam?

someone could have replaced lifters after a TB incident and valve head may have finally broken off.

While it was purchased, that was two years and 40k miles ago.

Have you tried rotating just the pump? Remove the pulley and put a couple bolts in the coupler and use a short bar so you aren’t torqueing the nut

Remove the belt, pull the cam and remove the GP’s.
Then bar the engine over using the crank shaft bolt.
If it still locks up then I’m afraid your gonna have to pull the head and possible the oil pan and play detective...... sorry.....

Tdijarhead said:

While it was purchased, that was two years and 40k miles ago.

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what do you mean by this ?

jimbote said:

what do you mean by this ?

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Sorry, I need to learn to be less brief on occasion. She bought her car 2 years ago and has put about 40 thousand miles on it since. One of the things I did immediately after purchase was to put a new Timing belt with all the associated rollers, water pump and tensioner on it.

I would have thought that a valve would have dropped long ago if that is indeed what has happened.

I throw out this possibility only because I did this just recently (and likewise figured something severe had happened): Any chance you replaced one or more bolts on the IP sprocket?

I decided to use the new IP bolts that were (surprisingly) included with my TB kit - oddly only two of them were in the package, though. Oh well, I'll just use one of the old ones and the two nice, pretty new ones.

Well, turns out those two bolts from the TB kit were NOT IP bolts, but rather, the short bolts that hold down the mount-to-body steel plate. Which look EXACTLY the same, except maybe 2-3mm longer, which is probably ~1mm too long. (smh)



I didn't get to the point of my engine running - I stopped at turning the engine over by hand when I hit the hard stop. And then puzzled over it for the better part of a day (plenty of other things to do on the car at that point) before I decided I'd take the IP sprocket right off and one of the bolts came out and looked....wrong.

Tdijarhead said:

Sorry, I need to learn to be less brief on occasion. She bought her car 2 years ago and has put about 40 thousand miles on it since. One of the things I did immediately after purchase was to put a new Timing belt with all the associated rollers, water pump and tensioner on it.
I would have thought that a valve would have dropped long ago if that is indeed what has happened.

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thanks for clarifying...they can drop a valve at any mileage after the incident occurred...not saying this is your issue but bad noises + #3 misfire point in that direction...you could pull #3 glow plug and injector to check for damage.

Possible that some part or debris got overlooked in the clutch end of the prior repair??

I’m going to pull the other two injectors and glow plugs and see if there is any damage to the tips of any of them.

However I had one more thought, I just replaced the clutch. The transmission is in neutral is there anything I could have done that is causing the flywheel not to rotate. I did find a chunk of the friction disk had broken off, which was the reason for the replacement.





The thread on these pics is here.

http://forums.tdiclub.com/showthread.php?t=506276

Thanks Jettawreck and Nuje I’m certainly looking for a simple solution, however I just pulled all of the glow plugs and injectors none of them seem to be damaged but the number three glow plug is very wet.

For Christmas this year I ask my girls for a bore scope and they got me one. It doesn’t quite fit into the injector hole but with it I can see some shiny metal down in the number three cylinder. Looks like the next step is to pop the head.

I guess at this point I’m wondering if it’s just valve piston contact or a dropped valve head. I’m leaning in the valve head direction.

Of course I know you guys will want to see carnage pictures if that’s the case.

Tdijarhead said:

I just replaced the clutch. The transmission is in neutral is there anything I could have done that is causing the flywheel not to rotate.

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Random possibility, but: all the original pressure plate bolts were used? No chance a longer one snuck in there by mistake?

Stranger things have happened, and when it comes to mechanical devices if something was working, and then some work was done. and then something stopped working... there can be surprising linkages.

Well gentlemen I wish it had been simple. Apparently sometime in the past valve/piston contact was made, probably not to bad maybe even at idle or some other unusual happening. My daughter has driven this car to Boston several times and to Texas once, no issues purred like a kitten.

Fortunately she was fairly close to home when the blessed event occurred.

Carnage pics for your inspection, number three cylinder.

Yep, unfortunately a victim of a previously compressed valve stem during the long since "event". Too bad when that happens.

Tdijarhead, sorry for the problem.
The silver bug I’ve been working on had a similar issue.
Originally bought it for my daughter as a grad present but found out it had more damage than was expected. That’s when I bought the yellow TDI from James.
PO,s mechanic botched TB job and bent a valve......didn’t tell owners, said a valve broke 10,000 miles later......puts a newer head on and doesn’t say anything to PO , he decides to sell it. I come and pick it up.
I do my normal routine and I’m not liking the cam so I pull the head....what the hell its only 10 bolts and a head gasket......well the under side of the head was pristine.....2 of the pistons look like someone beat it with a chisel and hammer.
I do a height check and find two of the pistons are bent.

I call frank , I send him all 4 pistons and connecting rods an a blank check....
He confirms two rods bent and rods weight are all off.

He matches weight , length , replaces two pistons with used ones , sends me new rings, bolts, main crank bearings and new connecting rod bearings for under $500.00.

I replace everything he sends me and car is running very nicely now.
I did ball the cylinders to clean them up.

Ouch. That sucks, especially if you just went through the work of putting a new clutch on it.


Double ouch if that valve really did last 40k miles before giving up the ghost. Makes one think real hard about buying any car if the owner can throw in a new set of lifters and it hides this kind of carnage for that long.


Although the skeptic in me wonders if this is somehow tied to that clutch failing. I find it hard to believe that two very strange occurences would happen so close together and not be in someway related. Could the clutch locking up have caused the valve to drop or timing to skip a short time ago? Or did the valve dropping cause the clutch to break? Or did you just get a bum valve and it had no previous incident? 40k miles seems a long time for a fractured valve to hang on as I thought they gave up around 10k miles usually.

Thanks guys, now that I think back when I put the new belt on after she bought this car I thought that the belt I took off looked really good. Of course I had no insight as to when the belt had been changed previously and of course we all know that most timing belts look pretty good still when their recommended change interval comes around.

I now think the clutch issue was a minor one I’m not even sure I would have found it if it wasn’t for the engine making all that noise. I was turning the engine by hand laying underneath the car. Not something we tend to do everyday. That’s when I heard the scraping noise coming from the bell housing, so naturally I thought I had the culprit, especially when I found the piece broke off the clutch disk.

Unfortunately this is extremely common after a timing belt incident if you don't pull the head and have it gone through. Usually it comes somewhere around 10k miles later, but one never knows exactly when it will happen.