HOT start Blue smoke

aracer · 07-25-2011, 03:17 PM

I'm looking to buy a 81 911 SC, 112000 miles. The car I'm interested in has an oil leak , 1st gear syncro bad, puff of smoke on hot start up. I'm having an inspection done on the car to get an estimate of what it would cost to fix these issues. But I also want to be some what educated first.

My questions are:

1. The oil leak are small drops on the ground. The oil does leak on the exhaust and burn from it. The owner says the leak is getting worse every year. Any ideas?

2. The car shifts into first but does grind a little. This is true when moving and I did not notice the problem when stopped. The owner said it has been an issue for 15 years he's owned the car. Should I replace the syncros or just deal with it?

3. When the car started cold (sitting for about a week) no smoke came from the exhaust. During my test drive there was no evidence of smoke. But after my test drive of 15 minutes the car was shut off. Then about 15 minutes later the car was started and a big puff of blue smoke was present. It was only a puff and did not continue after. I know it's burning oil. Can someone maybe give me some ideas what this symptom might indicate?

This will be my first Porsche so any help would be appreciated.

motogman · 07-25-2011, 05:34 PM

I bought an 81 SC with 58k miles on it about 2 months ago. It had been driven very little in the past few years.

I bought it knowing the 1st syncro was bad which was acknoledged by the PO. He had info on the cost of a rebuild etc. and knocked some $$$ off the price. However, I do not find it to be a big problem and it did not take long to get used to shifting and it is almost never an issue. The 915 (at least this one) is also a little notchy somtimes into second. I am not doing track events but enjoy spirited driving and no issue.

I also have several small leaks which again aren't a big issue but are a bit annoying. I have ventured to do some reconnisonce of the issues but have not undertaken to address them yet. My biggest drips appear to come from the oil lines to and from the oil tank. There may be a small drip from the oil drain cover but I haven't changed the oil yet. Mine also does a drip on the exhaust although small you can sometimes catch the odour if going a short distance. I don't seem to have any leaks about the valve covers or cylinders but this might be a place to look as this vintage can have head studs that break and need replaced.

When I first got this car, it had a cold start puff similar to what you describe. In the first 500 miles of driving the car it went through a quart of oil. I was feeling very bummed. Since adding a quart and driving it frequently and I am sure harder than the PO, it seems to have cured itself. In the past almost 1000 miles it has not used 1/4 a quart. I had a post asking about this but recieved no real insight. However, I do believe that the situation dissapated due to more usage. This was my experience and may be unique or maybe I am crazy....

With a car of this age there will be many things that need some attention but if your are interested in knowing the car you can get a wealth of knowledge and support on this site. Several of the questions I have had, have gotten quick and correct response from those here.

Good luck with your decision.

motogman · 07-25-2011, 05:35 PM

BTW - what body style and what is being asked? Any modifications?

aracer · 07-25-2011, 07:06 PM

Thanks for the info.. It's a Targa. Mostly original. Clutch was replaced with a performance clutch. Does not shift bad, clutch stiff. Car was well cared for with original shiny paint, no rust. $10500.

dhagood · dhagood's Garage

Quote:

Originally Posted by motogman

When I first got this car, it had a cold start puff similar to what you describe. In the first 500 miles of driving the car it went through a quart of oil. I was feeling very bummed. Since adding a quart and driving it frequently and I am sure harder than the PO, it seems to have cured itself. In the past almost 1000 miles it has not used 1/4 a quart. I had a post asking about this but recieved no real insight. However, I do believe that the situation dissapated due to more usage. This was my experience and may be unique or maybe I am crazy....

typical behavior. letting a car sit for years is not good for it at all. the seals harden, take sets, or adhere to things they shouldn't. when you start driving them again, it takes awhile for the seals to regain their functionality. in a lot of cases, the seals are permanently degraded.

the solution is to drive your car. if you do, ferry porsche will smile down upon you.

bkreigsr · 07-26-2011, 07:14 AM

Quote:

Originally Posted by aracer

.....$10500....

wow - nice buy!
Bill K

cgibson67 · cgibson67's Garage

I think its alittle risky to buy the car hoping that by putting some more miles on it and enjoying a couple italian tuneups will cure the problems. True, its happened before, and you could get lucky, but you also could be stuck with a problem costing 5-10k to have a shop fix.

There are some very nice SCs in the low teens that would need little immediate attention for sale now. I'd go for one of those.....or, if you don't mind working on it, try to do alittle better on the price and start chipping away at the issues. Working on these are half the fun for alot of owners.

motogman · 07-26-2011, 04:45 PM

Quote:

Thanks for the info.. It's a Targa. Mostly original. Clutch was replaced with a performance clutch. Does not shift bad, clutch stiff. Car was well cared for with original shiny paint, no rust. $10500.

Back to my experience... The clutch was very stiff and notchy when I bought it... It lossened up with use (as dhagood indicates). I also lubricated the helper spring (not sure this is the right name) and it works very smoothly now.

Quote:

I think its alittle risky to buy the car hoping that by putting some more miles on it and enjoying a couple italian tuneups will cure the problems. True, its happened before, and you could get lucky, but you also could be stuck with a problem costing 5-10k to have a shop fix.

.
As for being risky... any 30 year old car that you can not 100% verify the history on is risky. Although I think PPI is a good idea I did not have one done on my latest purchase. My past experience is that they can be helpful but if you think you are going to find a car with no issues it is highly unlikely and there are many things that may not show up in an inspection that will still bite hard. I think the independent evaluation is a good idea but should be assessed carefully.

It seems to me that SC prices have taken another notch down and the $10-14k range for decent cars is not unusual these days. Somewhat surprising given the capability of these cars and some of the comparisons that exist. I think the 10.5 for a low miles original car is a great buy if it is realitively problem free.