172 Screeching noise

[sand6000]

I have just replaced the cam belt and all the pulleys after collapsing one of the idler pulleys and bending the inlet valves. Have a spare motor so have changed over the complete head. also replaced the aux belt. All back together but after a 5 minute run there is a very loud screeching noise when revved over 2000rpm. Sounds like it is coming from the cam belt area.

I have checked all the relevant threads that I could find but nothing seems to be exactly like this problem.

Any help would be appreciated.

Cheers
Pat (New Zealand)

 

[sand6000]

It appears that I ovetightened the tensioner. Have readjusted and all is quiet except that engine is running pretty rough.

 

[Mr R.]

The auxiliary belt tensioner is spring loaded so you can not over tighten it.

Did you do the cam belt with the correct locking tools?

 

[sand6000]

Overtensioning was the cam belt.
I have the cam locking plate for the flywheel end only so adjust with the crank and cams locked and both pulleys slackened and then adjusted.

 

[craigy2703]

By looks of it these are very easy to get of timing and need to be spot on using the genuine tools your timing is most likely out