myflat6

Let's see if we can get some facts on the table for top end rebuilds
Two groups:
1) No rebuild and how many miles are currently on your car, and
2) Yes you had a rebuild and how many miles were on the car at the time.

KeninBlaine

I voted NO. My car had a top end job done at about 88k, but it did not include valve guides, which is what I think this poll is centering on.

myflat6

Good point. Looking for valve guide wear.

ilko

113K miles on the original engine of my '96 Carrera. Oil consumption is minimal. Last month I drove to Montreal and back followed by Indiana and back (close to 2600 miles altogether) with no oil consumption to speak of. Did pick up a few new rock chips though

bhensarl

134k on my '95 C2 with no rebuild. Still pulls strong, but I do have a small oil leak and add 1 qt every 1k - 1.5k miles.

mpruden

Yep - Previous owner at 110k miles. Poor guy. Cost him over $16k. Car failed smog and the dealership told him a valve job was the fix. As a side benefit, my engine bay looks pretty darn new as they took most the engine apart and resealed it. Have not had a drop of oil hit my floor yet. Kind of makes me think I got cheated out of the true Porsche ownership experience without the oil leaks.

axl911

Yep. Between 90 and 100K on both my 964 and 993. The 964 was valve guides. The 993 was exhaust valve causing a low leakdown.

IainM

Interesting.
I think we need more resolution for no >125kmiles

98k, no rebuild, kicks @$$ and only 1.5 qts between oil changes (5k miles) (I keep it between min an 1/4 on dipstick - barely registers on gauge)

Car25

The car was running fine but At 87K I had the top end done to thoroughly get at the SAI ports, 5 were completely clogged. Replaced valve guides and a bunch of other parts too. One of the cams had significant scoring on a lobe so those were replaced along with lifters.

saneproductions

All of my valve guides needed replacing when we did the rebuild at around 139k.

pp000830

Unfortunately the poll won't give us insight as to if the top end rebuild was necessary in all cases or the diagnosis was due to oil overfill related symptoms. I guess the message here is that if your car is consuming oil and you may also have other OBDC or running symptoms. Reduce your oil fill by a quart or so and see if your oil consumption is reduced. If the consumption subsides you may simply need to fill with a little less oil at your next fill and see if your intake needs a little cleaning from oil ingestion.

Andy

PS, not sure how to measure oil that is below the dip stick. I guess one could fashion a homemade dip stick from a fish tape and calibrate it to their car.

CHJ

This is a pretty big spread (from 50K to 120K). It sure would be nice to know what oil people are using and how long they have been using it.

Chuck

axl911

Oil type and interval got nothing to do with top end rebuild due to valve guides. (ZDDP is another issue.) Porsche 3.6 engine always have the valve guide issue. No pattern, rhyme, or reason when/if they show up. Search around. I believe Steve Weiner has commented on this.

I think the 3.2 Carreras is also prone to the valve guide issue. Remember reading an article somewhere about a 3.2 owner having to do a top end with about 30K miles on the clock.

CHJ

Don't some oils have more zinc than others?

Chuck

axl911

Yep. But from what I understand, the wear will be more at the camshaft and rockers. And the ZDDP issue is recent, several years ago.