Volvo AWD V70-XC70 Forum

INDEX FOR 1/2026(CURRENT) INDEX FOR 10/2002 V70-XC70 INDEX

[<<]  [>>]


 VIEW    REPLY TO THIS MESSAGE Replies to this message will be emailed.    PRINT   SAVE 

Testing for vacuum V70-XC70

posted by  KlausC on  Sun Jun 24 18:22 CST 2012
Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
last visit: Fri Oct 24 10:15 CST 2014
[RELATED]

Darn, hit return rather than tab...

There should be a small amount of negative pressure at the oil fill cap and the oil dipstick. It is not possible to get a negative reading on either one of those openings, but it should not be positive - meaning air blowing out.

The natural vacuum inside the intake manifold will draw a small amount of pressure from the crankcase, by design. If there were a large hose to the intake, the additional air would push the revs to breaking point.

So not having positive pressure is about the best you are going to get. A plugged PCT or vacuum line will cause the crank pressure to go positive. Same for a clogged oil separator.

On the older cars, the oil separator usually needed replacing by about 150K miles, mainly because the hoses degraded and cracked.





THREADED THREADED EXPANDED FLAT PRINT ALL
MESSAGES IN THIS THREAD

New Failed lower right motor mount.... oil leaking..... oh-oh [V70-XC70]
posted by  Hovonogila  on Wed Jun 20 18:42 CST 2012 >


<< < > >>



©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.