Burning Oil & Smoking

[John Camp]

Hello,

I am inquiring about a 1961 356B Super 90 engine. It is consuming a good bit of oil and smokes (especially under hard acceleration). I was thinking that replacing the valve stem seals might help the situation, but after reading through some posts related to this I am more confused than anything. I have read that the intake shouldn't have seals at all and it is debatable if the exhaust should. I am hoping someone has the knowledge to steer me in the right direction of how to alleviate the smoking and if it is valve seal related, I would love some insight and/or a reference to some information on whether and how to replace the valve stem seals.

Thanks for any help!

-John

[Thomas Sottile]

Get a compression test could be a bad ring drain the oil check for metal

[Jay Darlington]

Sounds like it needs to be torn down for an inspection In today environment those valves need all the lube they can get. if they are in good condition they don't need seals.
Jay D.

[Jules Dielen]

+1 do a.compression test, then a leakdown test and listen where it hisses. Exhaust, oil filler or carbs... none of the 3 is cheap

[Al Zim]

Ask people in your area where they are getting their AIR COOOLED Porsche's serviced. Take time to look at as many shops as you can. Talk to the owner and talk to his customers. If your car was a person it would be eligible for retirement and Medicare! Remember that when it comes to parts and labor!
Pay someone to help you ascertain the worth of your Porsche when it is done. Value for your investment should be paramount. al zim

[Martin Benade]

Some American cars are greatly improved by a set of valve stem seals, but that won’t fix a 356.

A leak down test would be informative, but it’s probably best to take it apart and start measuring and checking things. And split the case too unless you know a lot about its history and mileage.

[Al Zim]

Taking the engine apart usually takes the better part of 3 days which includes cleaning and correctly disposing of the oil. You will also have to dispose of the GASOLINE which is already trying to eat a hole in the tank. Get some trays to keep the hardware sorted. You will also need an engine stand VW (cheap) can be attached to one of the large (HEAVY DUTY) tables necessary for parts to be sorted properly. MOST IMPORTANT! See what fun it is to remove the flywheel! Take pictures. As you visit shops in your area you will realize what the necessities are.
EVERYONE: Finding lost or defective parts can be an overwhelming task. You do not just pick a camshaft design you tailor the correct one for your engine configuration. al

[George Hussey]

usually acceleration oil smoke is caused by piston rings, valve seal smoke or valve guide oil smoke happens when the downhill is pushing the engine. Chuck Allard could rebuild your engine for you or we do 356 engines here as you are close to Marietta relatively speaking. We have two 356 engines under reconstruction now

[Doug McDonnell]

Ray Morgan in Jasper might be able to help you also. VMRcars.

[Al Zim]

Mr. Camp: If wherever you are going is nearby stop by. We have engine restoration in process. al
I did not realize you were so far away!

[Harlan Halsey]

How many miles on that S90? S90s had iron coated aluminum barrels. At some point the upper compression ring wears through the coating into the aluminum. If your mileage is much over 40,000 I would suggest a leak down test and a bore scope look into the cylinders. Should a cylinder be worn out I think LN Engineering can renew the cylinders with a modern Nickasil coating. (Aluminum barrels are one of the neat features of the more expensive 356 engines. Something to retain.)

[Jay Darlington]

if its consuming a good bit of oil and smoking it needs taken apart, this will tell all. they aren't that hard to disassemble other than getting the flywheel off. if you have a shop near you they should be able to do it. once you get it apart and all the parts cleaned find someone or a machine shop near you and have all the parts inspected and measured. only then will you know the real damage. assembly is not difficult, IF you don't know something ASK HERE. many really knowledgeable people here can help you. Maybe not you, but i find it rewarding to do it myself.
Jay D.

[Chuck Allard]

Don't go taking it apart yet. Get someone to do a leak down test on the engine and a thorough inspection looking for signs of a prior rebuild (there are a few telltales). It might have been apart in the not too distant past and might not need a total rebuild. As others have pointed out, rings and cylinder head issues can account for a lot of smoke.

[Jay Darlington]

Don't go taking it apart yet. Get someone to do a leak down test on the engine and a thorough inspection looking for signs of a prior rebuild (there are a few telltales). It might have been apart in the not too distant past and might not need a total rebuild. As others have pointed out, rings and cylinder head issues can account for a lot of smoke.

so what would be the fix maybe a can of STP oil additive? i needs to come apart and fixed right. its most likely worn out, worn rings, worn valve guides, worn valve stems.
Jay D.

[Wes Bender]

Jay, that may very well be true but a leak down test first is still a good idea.