Merc/Indmar 5,7 - rattling noise after starup from the pulleys side of engine (video)

[ditri]

Hallo. Our Indmar 5,7 (year 2006) engine make rattling noise after cold startup. If the engine is warm, there is no noise. The noise is comming from the pulleys on the rear side of engine. Please can you help me identify the problem? Here is the video with the sound and noisy part of the engine...https://www.youtube.com/watch?v=HUwzjmvqxwc

 

[Bt Doctur]

I`ll take a guess either the water pump bearing or the idler pully bearing

 

[ditri]

Thank you so much for the info!!! One car mechanic tell us that is the timing chain. Can be this true? I think that the bearing as you said is more likely than the chain...

 

[Bt Doctur]

remove the belt and test for the noise

 

[ditri]

Thank you Bt Doctur. We will try it.

 

[Bt Doctur]

If you remove the belt you isolate the problem. noise still there= motor issues. noise gone=a rotating part issue water pump, idler pully, alt, ps pump.

 

[NHGuy]

With the belts removed spin the pulleys by hand. Butter smooth is good. Grainy and loud = bad.

 

[ditri]

Thank you guys. The probl?m was the belt. It was not tight. If we put some soap on it - the engine is quiet. I can trust - how many strange sound can do the not tight belt. Thank you so much!