Fan belt

[Sailfree]

Yanmar 75HP engine finding fan belt loose after say every 20hrs running.

No signs of distress, nor shedding powder and bolts are definitely not slipping. Original Yanmar replacement belt.

Thinking of adjusting it again and if loose after another 20hrs running replace.

Any opinions, have you had similar problems?

 

[RichardS]

I had similar problems with my Yanmars until I ditched the belt fitted and replaced with a Gates cogged belt of the exact right size, i.e. the outside of the belt is flush with the circumference of the pulleys.

I fitted the belt, adjusted it once after a few hours running which was 3 years ago and that was the first and last time it needed adjustment.

Richard

 

[pvb]

Over the years, there's been countless mentions of Yanmar belt problems. The usual advice is to replace with a Gates belt.

 

[dom]

Agree with above, I also had endless probs with the original v-belt, so switched to Gates cogged which sorted it. I also found Yanmar OEM belts a tad small to easily fit so I specced replacement 5-10mm longer which sorted that too.

 

[Sailfree]

Thanks. Never heard of problems with Yanmar belts.

Every day is an education!

Thanks will source a gates belt when in UK.

 

[cloud7]

Had same problem got pulleys polished was corrosion on pulley wheels

 

[fisherman]

When this happened to me it was Multiflex v belts, which failed after only a few hundred hours. Replaced with Fenner, IMO the best. I would change them usually every year, regardless, which would have been 1200-odd hours. Never had a failure.

 

[gus]

It is often well worth checking that the pulleys are exactly in line. The slightest misalignment will wear the belt and cause it to slacken.