Serpentine kit for Ample Power alternator

Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
I have an Ample Power 105A alternator on my M25XP with the stock 3/8" v-belt and I would like to upgrade the belt to serpentine with the 48-USP-M25 Balmar kit. Anyone know if the alternator pully in this kit will work on my Amply Power or will I need to get a different pulley?
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
I have an Ample Power 105A alternator on my M25XP with the stock 3/8" v-belt and I would like to upgrade the belt to serpentine with the 48-USP-M25 Balmar kit. Anyone know if the alternator pully in this kit will work on my Amply Power or will I need to get a different pulley?
M-25’s can be problematic to fit as there were different configurations. Can you post a pic of the crank pulley? There are J-10 pulleys that will fit the Ample alt but you’ll need to do some alignment work..
 
Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
M-25’s can be problematic to fit as there were different configurations. Can you post a pic of the crank pulley? There are J-10 pulleys that will fit the Ample alt but you’ll need to do some alignment work..
Thanks. I will be down at the boat in a few days and will take some photos and measurements. I have been working my poor old 3/8" belts too hard. Do i need to pull the alt pulley an get some photos and measurements from the shaft?
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
Thanks. I will be down at the boat in a few days and will take some photos and measurements. I have been working my poor old 3/8" belts too hard. Do i need to pull the alt pulley an get some photos and measurements from the shaft?
Just the crank is what is important. We currently build a beefed up up version of the old Ample small frame alternators so know what fits.

 
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Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
Just the crank is what is important. We currently build a beefed up up version of the old Ample small frame alternators so know what fits.

I am pretty sure that i have the crank on the right with the 3-holes but will check this weekend. I have the upgraded alt bracket.
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
I am pretty sure that i have the crank on the right with the 3-holes but will check this weekend. I have the upgraded alt bracket.
We can get you the right package so long as the crank pulley has the holes. Belts may need to be swapped, and alignment done, but otherwise pretty much straight forward. Alt pulley needs to be installed for 70 ft. pounds, and without the correct tools, this can be pretty tough.
 
Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
What are the "correct tools"? Is there a way to lock the stator and use a torque wrench or do you use an impact wrench?
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
What are the "correct tools"? Is there a way to lock the stator and use a torque wrench or do you use an impact wrench?
We use a special pass through socket and a torque wrench. Impact drivers typically under or over-torque. With the HP these are driving we only torque manually.
 
Feb 26, 2004
22,759
Catalina 34 224 Maple Bay, BC, Canada
Hayden, if you can't get a serpentine kit on your engine, consider using Small Engine Mode on an external regulator. I've posted about it here many times, so an advanced search should find them. I run a 100A alternator on my M25 (not an XP).

Here are links from our C34 site about SEM:

Alternator heat, Regulator Controls, Small Engine Mode

Alternator heat, Regulator Controls, Small Engine Mode

Small Engine Mode - discussion with link to the picture of the toggle switch: Alternator heat, Regulator Controls, Small Engine Mode

Small Engine Mode - the picture of the toggle switch Alternator Output Management with External Regulators [Small Engine Mode]

Good luck.
 
Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
Just the crank is what is important. We currently build a beefed up up version of the old Ample small frame alternators so know what fits.

Good day Rod. I finally got around to looking at this and verified that my crank does have the 3-holes shown on the right. I just finished cleaning and installing full sound insulation to the engine compartment and am not looking forward to turning all of that wonderful shinnyness black with belt dust.