Serpentine Belt replacement....Help!

[tphinney]

Background :

I'm noticing that my belt is starting to flake off some of the rubber pieces and I have loosened the tension pulley and removed it and restored it with no problems. Blets 4 years old now.

I called up Marine Max and gave them my engine serial number OM670xxx and my information ie power steering, Fresh Water cooled etc. and they gave me a replacement belt. mercusier part 57-865615003 ( 106.46" belt)

the problem :

when I go to put on the new belt it seems to be just a hair too short. even with the tension pulley all the way down/loose I can't get the belt over the last pulley.

it almost fits but not quite.

questions :

Do I have the wrong belt? it seems to be the biggest I have been able to find in the online parts searches an other 1/2" would fix my problem.

Are they really this hard to get on the first time?

will it strecth with time on the motor?

any help would be appreaciated.

thanks.

(Do it yourself'er in training)

 

[Turtlesboat]

I just bought a replacement belt online. part #57-863876-4. there were several options like -2 -4 etc... all for the same engine but the last number made it a different length. if you have your engine serial number, you can go to an online place and lookup your belt to see if it matches the one you have. try go2marine.com

 

[StressAweigh]

Tom If you still have the old belt you can put both side by side to check to see if you have the correct one. Also check the new belt and make sure it has the same number of ribs in it as the old one. In addition you may be able to take the old belt to Auto Zone and match it up with one that will fit. Good luck keep us posted.

 

[Dave S]

The belt will not stretch over time and should go on without having to force it. You may have the wrong size belt.

Dave

 

[MC1600]

Yeah, seems like they gave you the wrong size.

Instead of messing w/ MM, see if you can find a local shop that does mercruiser engine repair/replacement. I found out earlier this year that these belts are about 1/2 price ($50-some vs $100+) when they buy them in packages of 2 instead of individually. My local shop will sell me the leftover if they did a single engine swap. Also, make sure the tensioner isn't too tight. There's supposed to be a good bit of slack in that belt (versus what you'd be used to on a car for example). That may have caused the shredding.

 

[skibum]

Go to Mercury's web site and punch your engine serial number in. You will get a listing and diagrams showing all of the proper parts for your engine. There is also an 800# for Merc tech support. If there are any numbers at all still readable on you old belt, they may be able to give you a good part number.

Good luck,
Michael

 

[tphinney]

:smt038Update: Got the Belt on

boat now has 207Hrs on it with a new tank of quicksilver synthetic oil and a brand new serpentine belt. We are ready to get back out on the water (as soon as the thunderstorms stop).

So I contact the local Marine store/repair shop to see if they had a different size belt and they gave me the same size as I already had (which I didn't need since I already had one).

They also offered up some advice which made all the diference in getting the belt on.

1. loosen the tension pully all the way until its almost about to fall off.

and more importantly.

2. make the water pump pulley (large one in the middle ) the last one you try to slip the belt over. then once you have it bearly on tighten everything up and crank the motor over once or twice and watch the belt center it'self on that lest pulley.

Why is it that a job that seem's to be such a Pain in the A$$ is so easy once you have the insider trick :thumbsup:.

 

[Morpheus]

:smt038Update: Got the Belt on

boat now has 207Hrs on it with a new tank of quicksilver synthetic oil and a brand new serpentine belt. We are ready to get back out on the water (as soon as the thunderstorms stop).

So I contact the local Marine store/repair shop to see if they had a different size belt and they gave me the same size as I already had (which I didn't need since I already had one).

They also offered up some advice which made all the diference in getting the belt on.

1. loosen the tension pully all the way until its almost about to fall off.

and more importantly.

2. make the water pump pulley (large one in the middle ) the last one you try to slip the belt over. then once you have it bearly on tighten everything up and crank the motor over once or twice and watch the belt center it'self on that lest pulley.

Why is it that a job that seem's to be such a Pain in the A$$ is so easy once you have the insider trick :thumbsup:.

How do you know how tight to make it? Is there a trick to that as well?

 

[rondds]

i think the general rule with belts is just a bit of deflection (1/8 - 1/4") when you press down on it.

 

[tphinney]

Hey Morph;

Manual calls for about 1/4" deflection. basically since having dropped the belt off last winter to do the water pump impeller replacement; this basicly means get it as tight as you manually can and then check the defection across the widest point with you're finger. For me that is the span between the tensioner pully and the Alternator across the top of the engine.