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304065 304065 is offline
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Join Date: Dec 2001
Posts: 9,502
I don't disagree with that. The only thing I can think of is that it's been sitting for so long that the rings are stuck and could use some Marvel Mystery oil in the sump and in the fuel, and a good high-speed drive (such as the recovery drive back to NY) to loosen things up. This engine was rebuilt like 20 years ago, and has only about 12K since, so that would be about 600 miles or 10 hours of highway run-time per year. . . it wouldn't surprise me at all if that cylinder were carboned up, particularly if the car has been periodically started and NOT run up to operating temperature.

BUT the results are the results, and I'm not about to rationalize away the PPI's findings because I think there's an outside chance things could improve with time. In any case, it's a question of who should bear the RISK, and in this case it's certainly not me. (Do I sound like I'm trying to convince myself? No accident there.)

So what could be causing it? Here's my short-list:

Burned intake or exhaust valve;
Broken ring
Broken piston
Scored Cylinder
Leaking head to cylinder junction
Carbon deposit on valve(s)

That's just for jug #6. The compressions being off on two other cylinders are symptomatic of greater problems.
'66 911 #304065 Irischgruen
Ex-'71 911 PCA C-Stock Club Racer #806 (Sold 5/15/13)
Ex-'88 Carrera (Sold 3/29/02)
Ex-'91 Carrera 2 Cabriolet (Sold 8/20/04)
Old 02-25-2005, 08:39 AM
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