Silly Q's about P's and C's

[t951]

So, I have an 83 SC Cab. (Not a fan of Cabs, but I love the car). Anyway, I had the top end all redone. (PMO's, Oil tensioners, etc). Now, my car leaks like a sieve. It also burns a lot of oil. (A sort of batmobile smoke screen when I pull away from a light).

When I say it leaks alot, I mean that when I pull the car out the garage there is about a half quart to 3/4 quart of oil on the rubber matt. I haven't had a chance to see where it is pouring out of. I am asking the other questions due to the burning, not the leaking, unless, of course they are related.

My questions are:

If I replace the pistons, do I have to replace the cylinders (like a matched set)?

How can I tell if I need to replace them?

I am guessing that I need new rings. Is it smart to just replace the rings, or is this being penny smart, pound foolish?

Thanks for assist.

The other option of course is seeing if Wayne wants to swap 959 engine for mine, or just a total car swap......

t.

[cnavarro]

With the volume of oil you are reporting, I would check the source of your leaks - I had a 911T that had a lot of smoke and 99% of it was from oil leaking onto the exhaust - a leakdown showed 1% all the way around, so it wan't smoke from the guides or rings! Your engine might be fine, just that you need to reseal it :-)

[BURN-BROS]

here is a post you may be interested in

Re-ring Alusils?

[MKEDF]

I just bought a 78 SC 3.0...

I was told the engine was okay and that it could make it okay to San Diego this from Sparks, NV..

I did al the driving and everything was okay until coming close to LA..

Heavy traffic found on the way (4 hours almost) Until i got to San Diego the car started smoking..

I was really scared, then got the car to the Shop and as they brought down the engine, everything looked fine (83K miles on the engine), as taking out the p&c found one broken Piston, no scratches on the Cyls, they measure perfect, as i took other piston out, it looked perfect, but noticed a smal crack on the piston as i started handling it, rings began to disintegrate on my hands, next the slots also disintegrated on my hands I was told this happened because of low octane fuel, the thing is that the engine seemed perfect, but pistons started to disintegrate..then as teared down, there was more damage a broken head spring..worn out valve..conditioned the heads and now looking forward to finish the rebuild.....

[Steve@Rennsport]

TK:

The VERY first thing I would is perform a leakdown test to help find out the source of the oil consumption whether its leaking or burning.

A proper top end overhaul should have addressed the majority of oil leaks although you didn't mention how many miles are on your engine.

[Rich76_911s]

Inspect where the oil leak is comming from first. Couldn't the oil be leaking onto the heat exchangers causing all the smoke you are talking about.

[gigem75]

Silly answer, you haven't overfilled it have you. you wouldn't be the first.

[t951]

Wow, thanks for the info and ideas.

The easy stuff first. I did not overfill it. Actually, when I fill it so that the oil level in the gauge reads in the middle, the car leaves a lot. I fill it, go for a drive, and park it. When I take it out a couple of days later a lot oil is on the rubber matt.

I think there is something not tight enough or a missing gasket. I haven't had a chance to look deeply because florida in the summer is too hot.

How expensive is it too re-ring?

The car has 126k miles.

[TibetanT]

Subscribing for information purposes.

[cnavarro]

My first 911 did the same thing because it was overfilled, even though the gauge read in the middle.

My current 911, was bone dry, and I switched to M1 when I got it (don't use Mobil 1 anymore), and it started to leak badly. The oil return tubes, valve covers, cam towers, and something else also was leaking. All together, the cost to have a local shop fix all the leaks was somewhere around $2000 if memory serves me. There were other things done at the same time, like brakes, the front diff was also leaking so it got a complete reseal too (also because I switched to syn), etc. Now a year later, the 911 is bone dry.

I still think it's not the rings and oil leaking out onto the exhaust/heat exchangers.

[lindemans]

Originally Posted by cnavarro

With the volume of oil you are reporting, I would check the source of your leaks - I had a 911T that had a lot of smoke and 99% of it was from oil leaking onto the exhaust - a leakdown showed 1% all the way around, so it wan't smoke from the guides or rings! Your engine might be fine, just that you need to reseal it :-)

Reminds me of the penguin who went to the garage with car problems.
"You've blown a seal" the mechanic said.
"No", the penguin said, "I just finished my vanilla shake".

[304065]

Stay classy Haarlem!

[lindemans]

Originally Posted by john_cramer

Stay classy Haarlem!

I got this one from a very classy Australian lady colleague of mine; I appeared to be the only non-native speaker to get it...couldn't resist sharing it here.