Show full size
Discussion Forum of
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
 Technical FAQ924 FAQ (Technical)   Technical924 Technical Section   Jump to   Jump to PCA 924 Registry924 Registry

931 oil consumption

Post new topic   Reply to topic Forum Index -> 931 Tech.
View previous topic :: View next topic  
Author Message

PostPosted: Tue Apr 02, 2002 8:25 am    Post subject: Reply with quote

I haven't seen this topic mentioned lately, I apologize if it's been covered in the past. I've noticed my recently acquired 931 seems to consume what I'd consider a larger than normal amount of motor oil, like one quart per 200 miles or so. There is no puddle of oil in the driveway so I can only assume that it is being burnt somehow; there is no smoke that I can see coming from the tail pipe, but I do detect a little bit of an odor, not strong, just a 'trace'. My questions are: Is the quantity consumed normal? Are there any easy/cheap fixes? Am I ruining my engine if I leave it as is and just keep adding oil?

By normal consumption I meant for a 20+ year old car, I do realize the Haynes manual indicates oil consumption of approx. 1 quart per 400 miles, but that's when it's new.

Thanks for the help
Back to top

PostPosted: Tue Apr 02, 2002 9:16 am    Post subject: Reply with quote

I use about a quart every two tanks of gas in my '80 931. But, some of that is going on the ground. The most common place to loose/use oil is through the seals in the turbo charger. You will notice a puff of smoke on start-up after a hot run, and that is normal. However, if you seem some smoke under excelleration, it is probably time for a turbocharger rebuild. Another common place to use oil is around the valve guides. The valve guide seals tend to go rather early. You can check them by backing off in gear as you go down a hill. After a hundred yards floor it, and if the guides are bad, you will see a large puff of smoke. Hope this helps.
Back to top

PostPosted: Thu Apr 04, 2002 1:02 pm    Post subject: Reply with quote

I need about a quart every 1000 miles. Then again, I just rebuilt the turbo and don't have any leaks.
Back to top

PostPosted: Fri Apr 05, 2002 11:11 pm    Post subject: Reply with quote

My 931 uses about 1/2 litre in 5000 miles, but it's only got 30,000 on the engine and Turbo. However a single day of hard use on a track uses about the same amount of oil as 5000 miles on the road. I guess driving style has some effect on consumption then ?

Back to top

PostPosted: Sat Apr 06, 2002 6:38 am    Post subject: Reply with quote

Hey Tom, it's probably your turbo seals leaking. My '82 is also. I don't think it's hurting the motor though. I put some fuel injector cleaner/decarbonizer in my gas once in a while to keep the oil deposits out of my combustion chambers. From what I can see looking through the spark plug holes, it is pretty clean. I intend to rebuild the turbo as soon as I can afford to.

One thing you do have to do though is remove the catalytic converter. The oil in the exhaust plugs them up in no time. I'm assuming that you have a working cat since you are in CA. Pull it off and save it for the next smog test. -Troy
Back to top
Display posts from previous:   
Post new topic   Reply to topic Forum Index -> 931 Tech. All times are GMT + 11 Hours
Page 1 of 1

Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

Powered by phpBB © 2001, 2005 phpBB Group