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Finn
20-11-13, 10:58
What are the typical causes for a noisy (squeaky) cambelt? The waterpump and alternator are not the culprits. When cold the noise disappears but when run to normal temp the squeak returns.

The cambelt tensioner and the belt itself are new. I'm running without the balancer belt (the shafts are NOT locked).

I've had this noise for a long time but after recent cambelt change I decided to get rid of it once and for all, but not yet successful.
Brul(tm)
20-11-13, 12:01
When cold the noise disappears but when run to normal temp the squeak returns.

Most likely to much tension on the belt!
At least, that was the problem on mine once.
Finn
20-11-13, 13:53
Here's a short video of the noise.

http://youtu.be/4t5cZJUzVqE

I slackened the the belt a tiny bit (twice) as I was sure it was too tight, but maybe I didn't detension enough. The video was shot after de-tensioning. How slack dare I go...
wrinx
20-11-13, 17:24
Not sure it's a tension problem because the belt would be slacker when warm...what about the aircon and power steering pumps?

Are you sure all the idler wheels are good...have you removed the aux belt to confirm it's not that side?

wrinx
Finn
30-11-13, 17:13
The idler was the cause for the whining. I think the tightness of the belt was also contributing to the sound. I'm still uncertain of the correct tightness as the belt feels quite loose.
wrinx: I was reading Guy Croft's Lancia book and he said the belt gets tighter when it warms.
wrinx
30-11-13, 19:25
Ok, GC knows far more than I ever will...but it doesn't make sense to me :lol:

wrinx
jimnielsen
30-11-13, 22:34
It does get tighter as it warms up - this always seemed strange to me too Wrinx, but I can confirm it. I had a racecar version of this engine, and because it had no belt guards I could put my hands on the belts at anytime. You need 90 degrees of twist on the longest section when the belt is cold. From this state, after running the engine at 7000 rpm for a few laps the belt gets VERY tight..
wrinx
30-11-13, 23:31
Ok...a quick google suggests it's caused by the expansion of the whole engine, that's my useless bit of information for the day.

wrinx
Evodelta
05-12-13, 21:11
That's why they're prone to snapping or slipping, slack when cold, tight when hot.