Water Pump Pulley swap, 2000 3.0L

[RaceCarRich]

New boater, shredded an alternator belt today. Thanks to the search function and iboats, I know how to replace it. Also read a bunch on rusty pulleys. The only pulley that I have rust in the groove is the pump. All pulleys lined up nicely. And yes, I will be zip tying a spare belt in place. I plan on getting a 40" x 3/8" v-belt from Napa which I believe is roughly the size of the OEM part # 57-862054Q used in my application.

So here is my question... My motor has no power steering and only uses 1 groove of the 3 groove water pump pulley. I'm leery about how good sanding and refinishing would work since there is some decent pitting plus it doesn't sound like fun. So a new 3-groove pulley is $130-$165 range, ouch. Now I see some of the older 3.0L's used a single groove pulley 3927797af that was also used in a number of GM applications. This pulley is a dime a dozen. I saw a new one sell on ebay for $8 +s/h recently. Has anyone every replaced the 3 groove with the single groove and will it bolt up and more importantly line up with the crank and alternator?

Thanks

 

[alldodge]

New boater, shredded an alternator belt today. Thanks to the search function and iboats, I know how to replace it. Also read a bunch on rusty pulleys. The only pulley that I have rust in the groove is the pump. All pulleys lined up nicely. And yes, I will be zip tying a spare belt in place. I plan on getting a 40" x 3/8" v-belt from Napa which I believe is roughly the size of the OEM part # 57-862054Q used in my application.

So here is my question... My motor has no power steering and only uses 1 groove of the 3 groove water pump pulley. I'm leery about how good sanding and refinishing would work since there is some decent pitting plus it doesn't sound like fun. So a new 3-groove pulley is $130-$165 range, ouch. Now I see some of the older 3.0L's used a single groove pulley 3927797af that was also used in a number of GM applications. This pulley is a dime a dozen. I saw a new one sell on ebay for $8 +s/h recently. Has anyone every replaced the 3 groove with the single groove and will it bolt up and more importantly line up with the crank and alternator?

Thanks

Haven't done it but don't see an issue so long as it lines up and bolts on. For $8 I would think about buying one just to find out. Either that or go to a junk yard with your current one and see if they match up

 

[RaceCarRich]

Figured I'd share what I learned. The older single groove pulley used by Mercruiser (3927797af) is 7.2" diameter vs 6.25" for my 3-groove (73483T).

I looked through my car buddy's pulley bin and found a GM-367161BM. Its a 2 groove pulley that matched exactly with the two rear grooves of the 3-groove pulley that came stock on my boat and was same diameter and bolt pattern (and free).

Anyone needing a replacement pulley for a three-groover where the outer groove isn't used should keep this part number handy for the following reasons:

• Easier to find used in good condition (auto pulleys usually acquire less rust/pitting unless the motor was sitting outside). This was a very common GM pulley from late '70's.
• Cheaper
• Much easier to install / service. The outer groove on the stock pulley had to be pried over the motor mount stud and the nut had to be removed in order to clear it. The GM part does not have the outer pulley to deal with.
• Lighter for what its worth.

 

[alldodge]

Great info many thanks for sharing, will try to put this info in the file system