Mariner 225 EFI burning belts

[bltnme]

1996 Mariner EFIIMG_7216.JPGI have owned this engine for 3 years and maybe have put 50 hours on it.
I just toasted my 4th alternator belt. This time is jammed in the throttle body and she was stuck at 4000 RPM's to the ramp, thank god for kill switches.
The wheel on top of the motor is a little rusty, not bad. The wheel on top of the alternator is very rusty. The last time I had it replaced, it was done proffesionaly by a reputable shop, nothing was said about the corrosion or any other issues. My bigger concern is that there are both junks an dust inside the cowling and the throttle body shows signs of ingesting dust and junks.
Thoughts appreciated.

[Savage]

Rust kills belts......Pulleys shouldn't be rusting, possibly an aftermarket alternator.

[SilverFox579]

Need to remove ALL the rust on the alternator pulley and flywheel then repaint both. Unless you have access to a blast cabinet and have ability to spray 2 component paints, it might be easier to just replace the alternator pulley with OEM new.

[bltnme]

Thanks for responding. The pulley is replaceable? Assuming so, excellent. What kind of pint on the motor side?

[SilverFox579]

Yes, see the nut above the pulley? For the flywheel, stop by Mercury dealer and get a can of primer and black. Make sure all the rust is removed first.

[lpugh]

A slipping belt will make pulleys look like that in short order

[bltnme]

Thanks again everyone. Back on the water by Saturday ��

[lpugh]

After to replace the belt. Take a 15/16 socket (most alternators) and breaker bar and rotate the alternator in a clockwise direction. The belt should be tight enough to turn flywheel without the belt slipping, just don't over do it as that would be hard on the alternator bearings. scothbrite pads on the rust and a couple of light coat of rustoleom primer is all you need, don't paint the surface area where the belt runs as this would give you a false feel on getting belt tight enough. Recheck after your first trip out
99 % sure that is the result of a badly slipping belt

[JOE54]

QUESTION: any cowl mods done to this mtr, letting water inside cowl area on top flywheel area ???????

[bltnme]

No mods. Called dealer and was told the pulley is not replaceable. New alternator is $700 and not oem. Merc not making it any more. It sure looks replaceable. I’m going to see how smooth I can get it and take lpoug’s Advice.

[lpugh]

It is replaceable for sure, easily found at alternator/starter rebuilders, just provide shaft size and diameter as well as offset if applicable or manufacture of alternator and OE number not mercury number, Quite sure this will be a very common pulley that fits many different units, That pulley will clean up be fine, seen many far worse than that

[SilverFox579]

It is replaceable for sure, easily found at alternator/starter rebuilders, just provide shaft size and diameter as well as offset if applicable or manufacture of alternator and OE number not mercury number, Quite sure this will be a very common pulley that fits many different units, That pulley will clean up be fine, seen many far worse than that

+1. Better yet, remove the alternator and take to a local rebuilder for replacement, they might even do it while you wait.

[EuropeanAM]

Replacement pulley is not available through Mercury, but you likely CAN locate a replacement through an Alternator Shop.