P.S. V-belt question

DaveG55 · Aug 12, 2012

'94 Monterey 206SCR
5.0L / Alpha I, Gen II , Engine SN OF157289, Drive SN OF317617

Time to change the alternator belt so I'm going to replace the P.S. belt at the same time since it has to come off anyway. Today I took the numbers for both belts directly off the belts. The numbers are; Alt #57-816295 DF, P.S. #57-46120 DF. I can find the alt belt, no problem but I've been unable to find a belt that matches the ps belt #. I have the manual for the engine as well as a complete parts list and they indicate that there are 2 types of mountaing brackets, stamped and cast. I'm 95% positive I've got the cast mount but, since I did not know to speciffically check that, I'm not 100% on that. In any case neither belt number listed matches what I have off the belt in the boat. The number listed for the cast mount is 57-37619Q, a 52" belt. If I have the stamped mount then 2 belts are listed, 57-81295Q (52'5") and 57-37619Q depending on pully diameter - something else I did not know to check...
Anyway, I can find the alt belt but I'm unsure why I cannot locate the belt to match the number of the belt that is currently on it. Can anyone shed some light on this for me?
Also, is there any automotive equivilent for these belts? At $30 - $50/ belt (depending on the on-line shop) I'm wondering what is so special about these v-belts and would a Gates belt work just as well? If so, does anyone have Gates, or some other brands, numbers for the 2 belts?

Failproof · Aug 12, 2012

Re: P.S. V-belt question

Take it to a GOOD parts store, and have them measure it. They should be able to cross reference it. They are automotive belts. Make sure its the correct width, pitch, and lenght. Bout it

NHGuy · Aug 12, 2012

Re: P.S. V-belt question

The Merc belts on my motor say Dayco so sure it's ok to use Gates or any brand. And yes, a good parts guy can match by part #s, by eye, or by measuring with a belt measuring tool.

DaveG55 · Aug 12, 2012

Re: P.S. V-belt question

Yeah, I can do that and have done it for other belts before.
But, the boat's about 70 miles from home, at the lake house, and I'd like to have the new belts in hand so I can do a quick swap. I really don't want to waste time pulling them off, finding an auto parts store in the little town near the lake and hoping that the counter guy has enough sense to match the belts properly.
That's why I'm hoping someone has got parts numbers or know some way to cross reference them...

DaveG55 · Aug 13, 2012

Re: P.S. V-belt question

bump

04fxdwgi · Aug 14, 2012

Re: P.S. V-belt question

DaveG55 said:
'94 Monterey 206SCR
5.0L / Alpha I, Gen II , Engine SN OF157289, Drive SN OF317617

Time to change the alternator belt so I'm going to replace the P.S. belt at the same time since it has to come off anyway. Today I took the numbers for both belts directly off the belts. The numbers are; Alt #57-816295 DF, P.S. #57-46120 DF. I can find the alt belt, no problem but I've been unable to find a belt that matches the ps belt #. I have the manual for the engine as well as a complete parts list and they indicate that there are 2 types of mountaing brackets, stamped and cast. I'm 95% positive I've got the cast mount but, since I did not know to speciffically check that, I'm not 100% on that. In any case neither belt number listed matches what I have off the belt in the boat. The number listed for the cast mount is 57-37619Q, a 52" belt. If I have the stamped mount then 2 belts are listed, 57-81295Q (52'5") and 57-37619Q depending on pully diameter - something else I did not know to check...
Anyway, I can find the alt belt but I'm unsure why I cannot locate the belt to match the number of the belt that is currently on it. Can anyone shed some light on this for me?
Also, is there any automotive equivilent for these belts? At $30 - $50/ belt (depending on the on-line shop) I'm wondering what is so special about these v-belts and would a Gates belt work just as well? If so, does anyone have Gates, or some other brands, numbers for the 2 belts?

The Alternator belt should be a Gates 7*** series belt. I believe you PS pump uses a smaller (1/2" diameter belt that the rest). A 52" belt would likely convert to 7520 Gates number. The differance between the 52 and 52.5 seems kind of minimal and may be able to be taken up in the adjustment, as it would only 1/4" of pulley movement to compensate.

Here's what Gates says http://www.gates.com/part_locator/index.cfm?location_id=3002

Mercruiser 5.0 L Mercruiser V-8 305

Application

Product Type

Part #

Comments

Belt Drive System

Front End Accessory Drive Components

W.P. & Alt.; W/45 3/8" Belt O.C.