Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > 911 Engine Rebuilding Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered
 
Join Date: Oct 2005
Location: Western Massachusetts
Posts: 214
How do these compression numbers look?

Hi, I initially posted this question on the technical forum, but have not had much feedback yet. My apologies for posting here also.

My 66 2.0 is leaking oil out the breather vent after running the car for a while. It did not leak after a 10 minute idle, but it did after a 10 minute drive. At that point the oil seems to be blowing out the vent.

At the suggestion of John C. I did a compression check. Here are my compression numbers.
130
121
118
110
111
120
Would these explain the oil blow-by? I was expecting the compression to be lower. While I am sure that the engine could benefit from a top end rebuild, I would rather not start it at this time. I am in the middle of a 2.2 teardown and would rather get that one finished if possible. Another friend suggested that since it only seems to leak when hot, that maybe the oil thermostat is not working, or possibly the oil cooler is blocked. Anyone have any ideas?
Thank You,
John

__________________
1965 911 #301069 Light Ivory, 1965 911 #301983 Silver
1966 911 #302963 Polo Red, 1966 911 #302222 Irish Green
1967s, 1968 912 ,1969t, 1970s, 1970t, 1970 914-6, 1971e, 1972t, 1973.5t, 1976 914, 1987 911 Targa, 1991 Cabriolet
Old 02-22-2010, 12:53 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered
 
E Sully's Avatar
 
Join Date: Nov 2008
Location: NY
Posts: 3,977
Garage
Your numbers are low. I would say it could be worn or broken rings, causing the crakcase to be pressurized. If you can do a leak down test you will have a better idea. I wouldn't drive it till you have a better idea.
Old 02-22-2010, 12:59 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered
 
Join Date: Sep 2008
Location: Rio Rancho, New Mexico
Posts: 200
Yes, your 2.0 engine is tired and in need of some top end work.
A leakdown test will likely tell you what you already know, lots of byass from worn rings/pistons/cylinders from this 44 year old engine.
Time to get busy with the 2.2.

__________________
Doug
Was 2.7racer.
'76, 2.7 w/Webers, JE pistons, Solex cams. Elephant bushings front & rear, 23mm & 28mm torsion bars, big brakes front & rear, Pertronix. Track car.
'85 3.2 stock, Orient red, comfy street car.
Old 02-22-2010, 03:18 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Reply


 


All times are GMT -8. The time now is 11:24 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.