Yamaha F75 Timing Belt Replacement

[ggray]

2003 motor (bought "new in the box" in '07) with light usage, maybe 500 hours.

Timing belt looks virtually new, but I know the consequences of failure, so think I should replace it.

I have changed these on automobile engines; is this much more difficult? It looks like the flywheel needs to be removed, so that's one extra step.

I've seen a pdf file on this forum from a service manual for larger Yamahas, but not for the 75.

Does anyone know where that might be found?

Thanks!

 

[alldodge]

Not a Yam guy but since no one has commented I say this. I'm not sure it has a timing belt which controls the valves, only the spark. With that look here and use the search function to bring up the belt

http://boatinfo.no/lib/yamaha/manuals/1997-2003yamaha.html#/0

 

[ggray]

Thanks for chiming in, but this is a four stroke engine with a cogged belt that rotates the camshafts.

 

[ggray]

The link is for a manual covering only 2 strokes, but I was able to use it to find one for a Yamaha 100 hp 4 stroke This gave some info, but I think I better get the manual for a 75 hp.

 

[tommarvin]

I agree, better get the manual for a 75 hp, and all the torque settings, HF has a 20-200 inch pound torque wrench about 15 bucks

 

[dingbat]

Never fix anything that isn't broken.

Change interval for timing belt is 1000 hours

 

[ggray]

Yeah, but if that belt breaks, lots more to fix!!

 

[tommarvin]

If you have injectors, there's diagnostic software on E-Bay for 65 bucks, includes the cable, to diagnose problems,log all maintance. You need a laptop or tablet to run it.

 

[lakensea]

If you have injectors, there's diagnostic software on E-Bay for 65 bucks, includes the cable, to diagnose problems,log all maintance. You need a laptop or tablet to run it.

If you knew anything about Yamaha's you would know if it was EFI. And what does that have to do with a timing belt anyways?

 

[Seahawk170]

Intersting question. My F90 (new to me) is the same block, so I'll be interested to hear the answer.
Personally, I'd like to know if this engine has a valve interference designed head on it. If interference designed, then a major repairs if it breaks while running.
Since you mentioned that it still looks new, then I'd just keep an eye on it for every couple hundred hours of use.