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Engine work (tensioner failure) concerns?? on something I might buy

I'm looking at an 81 that has had a tensioner failure. It didn't have the upgrade
It does now.
Anyway, apparently there were some bent valves due to the failure. The valves were replaced (costing 4K). And supposedly the engine doesn't leak a drop of oil (hard to believe) now. So I'm going to get a ppi on the car and will have compression numbers.

If the numbers are good what else should I be concerned with relating to the failure and repair?

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Old 07-29-2008, 06:51 PM
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Old 07-30-2008, 03:21 PM
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I would be interested to know whether all the valves were replaced, or whether just the bent ones were replaced. Also, while they had the engine apart, did they replace anything else? If the engine had more than 125K miles, then I would expect the rings to be a bit worn. And the valve guides. And that would also be a good time to replace the exhaust-side head studs. If these things were not done, or at least looked at, then I would be disappointed.
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Old 07-30-2008, 03:35 PM
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Quote:
Originally Posted by khamul02 View Post
So I'm going to get a ppi on the car and will have compression numbers.

If the numbers are good what else should I be concerned with relating to the failure and repair?
1. Get leak down numbers instead - compression doesn't tell you as much.

2. Check the repair invoice for "cylinder head studs", they should have replaced the lower 12 studs.

3. With bent valves there is always a small chance that rod bearings have had damage, and that damage might take 1,000 miles after the repair to become obvious. Were the rod bearings replaced and the rods checked by a machine shop?

http://forums.rennlist.com/rennforums/showthread.php?t=189606&highlight=PPI+by+Peter+Zimmermann
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Old 07-30-2008, 03:37 PM
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Quote:
Originally Posted by Superman View Post
I would be interested to know whether all the valves were replaced, or whether just the bent ones were replaced. Also, while they had the engine apart, did they replace anything else? If the engine had more than 125K miles, then I would expect the rings to be a bit worn. And the valve guides. And that would also be a good time to replace the exhaust-side head studs. If these things were not done, or at least looked at, then I would be disappointed.
The engine supposedly has 115K on it. The guy mentioned that he thought only the bent valves had been replaced. And he wasn't sure what else was done at the time. I'll be able to look over the car and receipts Sunday.

I'm hoping that additional work was done while the engine was out but I am in Mississippi and the work was done here which is very scary.
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Old 07-30-2008, 05:23 PM
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Quote:
Originally Posted by Peter Zimmermann View Post
1. Get leak down numbers instead - compression doesn't tell you as much.

2. Check the repair invoice for "cylinder head studs", they should have replaced the lower 12 studs.

3. With bent valves there is always a small chance that rod bearings have had damage, and that damage might take 1,000 miles after the repair to become obvious. Were the rod bearings replaced and the rods checked by a machine shop?

http://forums.rennlist.com/rennforums/showthread.php?t=189606&highlight=PPI+by+Peter+Zimmermann

I'll go with a Leak down and full ppi at the local dealership on Monday. Although my guess would be there is little to no experience with Sc/eighties 911s there.

I hope to find out what was done during the repairs Sunday but I would guess there was no machine shop involved. In fact, I have been told by a local mechanic that the local machine shops are worthless due to their flexibility concerning tolerances.

Hopefully, I'll have time to take a good look at the car, get as good of a ppi as possible here, and have several days to make a decision.

The price is really, really good, which is a bit scary. The interior of the car is suppose to be almost perfect, which hopefully says something about the care of the car.

I relied heavily on your book for my first 911 purchase 3 years ago and things went great with that purchase. I'm still very satisfied with that car. Hopefully I can make a clear decision one way or the other in this case.
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Tom Hutchinson
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"If one does not fail at times, then one has not challenged himself." Ferdinand Porsche
Old 07-30-2008, 05:40 PM
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Quote:
Originally Posted by khamul02 View Post
I'll go with a Leak down and full ppi at the local dealership on Monday. Although my guess would be there is little to no experience with Sc/eighties 911s there.

I hope to find out what was done during the repairs Sunday but I would guess there was no machine shop involved. In fact, I have been told by a local mechanic that the local machine shops are worthless due to their flexibility concerning tolerances.

Hopefully, I'll have time to take a good look at the car, get as good of a ppi as possible here, and have several days to make a decision.

The price is really, really good, which is a bit scary. The interior of the car is suppose to be almost perfect, which hopefully says something about the care of the car.

I relied heavily on your book for my first 911 purchase 3 years ago and things went great with that purchase. I'm still very satisfied with that car. Hopefully I can make a clear decision one way or the other in this case.
Good luck with the car, hopefully the mechanic who did the work was smarter than the average bear and sent out the involved components to a P-car competent machine shop for repair!
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Old 07-31-2008, 07:39 AM
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Hey Tom,

Is this the 'ice cold" white car... Hope the numbers work out for you. If they are good, seems like a pretty good buy...

Shane
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Old 07-31-2008, 07:50 AM
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Shane,
It is, but I'm a bit worried about it. I'll know more after I look at it and get a ppi.

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Tom Hutchinson
80 Targa / 81 Coupe / 71 Targa (in Porsche heaven)
My Garage Build: https://youtu.be/H0n_NwEQVbs
"If one does not fail at times, then one has not challenged himself." Ferdinand Porsche
Old 07-31-2008, 08:51 AM
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