The message to which you are about to reply is shown first. GO TO REPLY FORM



 VIEW    REPLY TO THIS MESSAGE    PRINT   SAVE 

Knock by front exhaust cam during warm up

posted by  Dave Stevens on  Sat Oct 7 16:31 CST 2023
Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
last visit: Sun Jan 1 02:36 CST 2012
[RELATED]

Check timing belt tension. Timing belts can harmonically flutter on the long span after the crank pulley on the exhaust side, make noise and even touch the cover. Belt length affecting tension and belt flexibility will vary by temp, which would change the flutter. The DOHC B234F (for example) has a small stainless steel wear plate on the inside of the cover at the mid-span point for that reason. If you've got an automatic hydraulic tensioner then it may be slowly failing (I didn't check, but I'm guessing you do, especially if it's an interference engine). Inspect carefully at the base of the pulley arm to see if there's any hint oil residue indicating a leak. Other than measuring belt tension. there is no good test of hydraulic tensioners that have only started to go. They are considered a wear item and need occasional replacement.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now






USERNAME
Use "claim to be" below if you don't want to log in.
PASSWORD
I don't have an account. Sign me up.
CLAIM TO BE
Use only if you don't want to login (post anonymously).
ENTER CAPTCHA CODE
This is required for posting anonymously.
OPTIONS notify by email
Available only to user accounts.
SUBJECT
MODEL/YEAR
MESSAGE

DICTIONARY
LABEL(S) +
IMAGE URL *
[IMAGE LIBRARY (UPLOAD/SELECT)]

* = Field is optional.

+ = Enter space delimited labels for this post. An example entry: 240 muffler


©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.