Yamaha F25ELHZ 25 HP four stroke timing belt

[oceancpt]

Hello all,<br />What is the reccomended time/hours interval for timing belt change on these motors? <br />Thanks.

 

[rodbolt]

Re: Yamaha F25ELHZ 25 HP four stroke timing belt

its inspection evey 200 hours or 1 year and replacement at 1000 hours or 5 years. you really really need a service manual. skip an oil change and buy the manual. the inspection procedure is in the manual as is the valve lash checking procedure.<br /> that motor is refered to as a non interference motor so if the belt does break no engine damage should occur due to valve to piston interference.<br /> the service intravels are in both the service manual and the marine tech guide but the service procedures are only in the service manual.

 

[oceancpt]

Re: Yamaha F25ELHZ 25 HP four stroke timing belt

Thank you again rodbolt! After spending sometime on the site I see that you are a legend here. I will ask that the belt gets a detailed inspection during its 200 hour service, as the engine will be 5 years old in June. I will leave it to the professionals to change it. I only do my best to keep the motor well oiled, cooled, and clean to prevent corosion. The rest is best left to the people who work on engines all the time. Thanks again

 

[rodbolt]

Re: Yamaha F25ELHZ 25 HP four stroke timing belt

no worries, the 5 year intraval is a guidline. if your belt slack is in acceptable limits and not fraying nor craking odds are it will live. and as that motor is a non interference motor if it breaks it will stop running but wont wipe the engine. but do ask for the pages I posted. makes both feel better about the work performed.<br /> I am NOT a legend, I apperantly have no life

 

[oceancpt]

Re: Yamaha F25ELHZ 25 HP four stroke timing belt

If you enjoy what you do with your time then you do have a life. It's a BAD! feeling when your engine quits on you. No matter what boat you are on. In 03 I crossed san pablo bay in not so good set of conditions. Then onto the petaluma river WOT, she quit.Gas coming out of the carb. I was thankfull she did not quit in the bay. after draining the curb she started right up. But ever since then the fuel tank gets cleaned right before she goes on the dry. Usually around Thanksgiving. She sometimes ventures passed the Golden Gate bridge. I do all that is required and hope I never loose power again. I am not worried about the T/B breaking though if it looks good and it's tight enough. Thanks again.

 

[rodbolt]

Re: Yamaha F25ELHZ 25 HP four stroke timing belt

if you took away the customer/lack of maint fuel problems and the customer/lack of cooling system maint problems I would be on welfare.<br /> the amount of actual problems with the gear is very minimal, however if the CDI on your 25 says motoraloa its a mercury with a silver/blue paint job and the electronics typically are not as bullet proof as hitachi stuff. however so far I have only seen two motorola CDI units fail and one does not count cause the engine had gone swimming at the inlet.

 

[oceancpt]

Re: Yamaha F25ELHZ 25 HP four stroke timing belt

Aah, good point. I will check into that tomorrow. The CDI I mean.I do know that either the cylinder head or the block is made by Mercury, hence the above than average noise for a 4 stroke. <br />By the way, I 've been using yamaha ring free in the fuel ever since the engine passed it's break in period. Do I need to perform decarbonization once in a while? <br />Also the gear case always gets mercury high performance gear oil, I like the staff. I am not sure about the yamalube 10/30 I use though, that's why the longest I went without an oil change is 50 hours. There is always something better i quess the key is care and maintenance.<br />The other thing is: Is it better to drain the curb or let stabilized fuel in it? When I do drain the carb, I turn the engine over with the drain screw removed in hopes that any residual fuel gets pushed out of the curb. I do that after I spray fogging oil into the cylinders. Ah, all these questions, no wonder you feel like you have no life.

 

[rodbolt]

Re: Yamaha F25ELHZ 25 HP four stroke timing belt

the oil change cycle may be excessive but at less than 2qts its dirt cheap. tipping the engine may be a bit overboard as it will drain anyway. the HP gear lube is a tad pricy for the application but is a superior oil. in anycase seems what your doing is working so keep it up.<br /> the reason for the noise is that motor has 2 firing pistons and 1 balance piston and adjustable overhead valve rocker arms.<br /> all in all a decent engine though.<br /> 90% of the problems trace back to contaminated/old fuel.