squeaking engine when throttling up. Stops when up to speed

[bufcopper]

I have a Volvo Penta 431 and when I start it, There is a squeaking noise coming from engine. Also same noise when revving or throttling. The noise stops when I get up to speed. How do I tell if it is loose belt or water pump bearings?

 

[sandkicker]

Check belt tension/tighten belt... still have problem, either water pump or alternator bearing... or an idler pulley if you have one.

Or... you could open hatch and carefully watch/listen front of engine while someone else plays with throttle. Sometimes with belt slip you can see one or more pulleys briefly not turning at normal speed.

 

[kimcrwbr1]

How old are the belts? If unknown start with preventive maint first replace the belts and go from there.

 

[bufcopper]

Checked and replaced power steering belt and all is well. Thanks all for the responses.