|
|
|
|
| Author |
|
|
Registered
|
Smoke
I'm trying to bring a 72 911E back to life after 17 years of sleep. Followed all the steps (compression, spark, timing, filter, fuel pump etc) and renewed some bits and pieces. At idle she runs fine now. But at higher revs, lot's of (blue) smoke. Any thoughts what causes this?
Ed |
||
12-07-2009, 06:43 AM
|
|
|
Woodland Hills, CA
Join Date: Dec 2008
Location: Southern, CA
Posts: 634
|
Sounds like rings. Smoke on decel would be valve guides. You might get away with re-ringing the cylinders as long as the barrels aren't too egg shaped or deeply scored. Perform a valve job while your at it. Good Luck
|
||
|
12-07-2009, 07:16 AM
|
|
|
83 CHECKER
Join Date: Jun 2008
Location: Saratoga N.Y.
Posts: 611
|
Blue smoke generally means burinig oil, perhaps crap stuck in a valve or worn or stuck rings. On the flip side, change the oil, adjust the valves, get her good and warm then run the snot out of her, clear her out and quite often the problem goes away. That cars been sitting 17 years, very well may have been put away tired at 21 years old, amazing you got it running as easily as you did. Best of luck, great car!
__________________
'83 911SC CAB '90 ZR-1 '68 TR-250 |
||
|
12-07-2009, 07:17 AM
|
|
|
Registered
|
Believe me, it was not easy. Had to replace many things like hoses, ignition cables, filter, solenoid, spark plugs, alternator etc etc. But at least she's running at idle. Recalibrated MFI is on the way so hopefully that will improve her even further.
About the rings, leakage test was good. Doesn't that exclude the rings (but leave the valve seals in)? |
||
|
12-07-2009, 07:35 AM
|
|
|
83 CHECKER
Join Date: Jun 2008
Location: Saratoga N.Y.
Posts: 611
|
Do a leakdown and compression test. That will point you in a direction. Be it valves or rings.
__________________
'83 911SC CAB '90 ZR-1 '68 TR-250 |
||
|
12-07-2009, 08:13 AM
|
|
|
Registered
|
Thanks, smoke much less after a 20 min test drive. Hope rest will go away after more driving.
Merry Christmas, Ed |
||
|
12-24-2009, 07:47 AM
|
|
|
|
Friend of Warren
Join Date: Oct 2000
Location: Lincoln, NE
Posts: 16,497
|
Good chance that over the years oil just leaked past the rings and into the cylinders. I agree that you should take it on a good long drive and see if it burns off.
__________________
Kurt V No more Porsches, but a revolving number of motorcycles. |
||
|
12-24-2009, 10:16 AM
|
|
|
GAFB
Join Date: Dec 1999
Location: Raleigh, NC, USA
Posts: 7,842
|
You may just be burning residual oil in the heat exchangers. That can take a loooong time. I'd run some Techron through the fuel system, drive the snot out of it for a few weeks, then do a plug cut and leakdown test. Sort of the 'crystal balls' of engine health - see what those tests tell you after a few weeks of exercising the motor.
__________________
Several BMWs |
||
|
12-24-2009, 10:20 AM
|
|
|
Registered
|
Thanks, also have some smoke/oil smell in the cabin so suspect the heat exchanger.
Merry Christmas! Ed |
||
|
12-24-2009, 11:44 AM
|
|
|
Registered
|
What weight oil did you use?
|
||
|
12-24-2009, 12:20 PM
|
|
|
Registered
|
The one exactly on Porsche specification.
What do you mean with weight? |
||
|
12-24-2009, 01:15 PM
|
|
|
Mike Holbrook
|
Marvel Mystery Oil in the fuel. Rings are probably gunked up too. Drive it and when going down hill, drop down a gear and coast to let the engine vacuum help clean it up.
__________________
Mike Holbrook Meridian, ID 1979 911SC Targa |
||
|
12-24-2009, 04:24 PM
|
|
|
|
Registered
|
Thanks all. Smoke is gone after a long test drive (and a bit of an Italian tune up).
Saturday some fine tuning is needed because the car backfires a bit and is loosing power after cruising a couple of minutes. Ed |
||
|
01-01-2010, 03:24 AM
|
|
|
sancho
Join Date: Sep 2008
Posts: 129
|
try tuning the ignition up to the factory specs,
__________________
1980 SC targa blue-SOLD 1986 Carrera wide body white |
||
|
01-01-2010, 04:05 AM
|
|
Kermit
Rust Rocket
Madone
Rowdy
