Large Frame alternator in M25XP

Jan 11, 2014
12,027
Sabre 362 113 Fair Haven, NY
And even prettier when installed. ;)

Did you get the belt buddy too? I found the standard arm could not cope with the increased load from the larger alternator.

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Apr 5, 2009
2,911
Catalina '88 C30 tr/bs Oak Harbor, WA
Well, I started the install today and it defiantly fits. The large frame is only a bit bigger than my old Ample Power 100A that it is replacing. I will need to create a new adjuster arm because the old one is too short.

I found a remote oil kit that works with my XP which will be a nice addition.
Size comparison between new and old. The new sure has a lot more cooling ventilation and the 12-diode rectifier with large heat sink should work cooler than the old 6-diode configuration in the Ample.
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Front view. I will need to lift the engine about 3" to install the crank pulley. I did the motor mounts a couple of years ago so that will not be a challenge.
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Top view. Lots of room for new alternator.
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I am hoping to install an Hiem adjuster as was suggested by Rod Collins but not sure what I could attached to down here. One though is to make an angle bracket that bolts to the top side of both port side engine mounts and use the motor mount bolt to hold it in place. The end would then cantilever out past the front mount to provide an anchor for the Hiem.
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I am installing a forced cool air duct which will bring cool bilge air through the foam insulated firewall and blow it directly into the rear ports into the rectifier heat sink.
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This picture shows the fan mount coming through the foam.
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This is the model of remote oil filter I found. The inner O-ring has an OD of 2.5" and fits the filter flange on the M25XP perfectly.
8 remote filter.jpg
 
Apr 5, 2009
2,911
Catalina '88 C30 tr/bs Oak Harbor, WA
Well, my installation was going swimmingly right up to the point where I tried to install the Balmer drive pulley from my serpentine belt kit. It is 64-thousants less than the original pulley and no amount of lube will get that to fit. :banghead::banghead::banghead:
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
21,845
CAL 35 Cruiser #21 moored EVERETT WA
How is it intended to fit and hold on the shaft? Do you need to heat it and press fit? Does the pulley have set screws?

What have you heard form Balmer?
 
Apr 5, 2009
2,911
Catalina '88 C30 tr/bs Oak Harbor, WA
How is it intended to fit and hold on the shaft? Do you need to heat it and press fit? Does the pulley have set screws?

What have you heard form Balmer?
Phe pulley is intended to mount over the top of the factory drive pulley and be clamped to it by using the three holes in the pulley intended to be used with a puller in removing the pulley. It should be a close fit with a couple of thou clearance. I haven't heard from Balmar because I did not discover it until 6:00pm on Friday. They are based out of Marysville which is only about 55-miles from me but still frustrating.

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jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
21,845
CAL 35 Cruiser #21 moored EVERETT WA
Balmar was a part of PYI. PYI is headquartered in Lynwood.

Balmar was bought by CDI electronics a few years ago and moved to Huntsville Alabama.

CDI Electronics |
353 James Record Rd. SW |
Huntsville, AL 35824
 
Jan 11, 2014
12,027
Sabre 362 113 Fair Haven, NY
Balmar is now owned by Dometic. A machine shop should be able to remedy the problem.
 
Apr 5, 2009
2,911
Catalina '88 C30 tr/bs Oak Harbor, WA
Their web site lists a Marysville address which would be far closer to me than Lynnwood. I do not relish the idea of paying for a machinist to rework a brand-new Item that I paid $450 for which should be built specifically for this engine.
 
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Apr 5, 2009
2,911
Catalina '88 C30 tr/bs Oak Harbor, WA
I ended up needing to pull the front balancer pulley from the engine and take it to a machine shop that cut the edges of the V-bely pulley down to fit the drive wheel. The end result was a perfect fit although I could have done without the $137 in tools and machinist fees.
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I have the alternator installed and needed to fabricate a new adjuster arm because the new large frame is about 1/2" larger diameter and the new belt causes the alternator to rotate farther away from the exhaust manifold which is a good thing. I really did not like the old adjuster given that there was about 150º at the pivot bolt from the adjuster anchor at the mount and the alternator. This creates a lot extra load into the mount which is not needed. I fabricated an angle that bolts to the top of the motor mount flanges and supports a hiem link that has much better geometry and completely removes all loads in the adjuster from the alternator mounting bracket. I used a light perforated angle that I could nibble away at until I was happy with the fit and then had a welder make up the final. Completely thrilled with the final results.
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Here is a Flir shot of the first test run. The alternator had been putting out 100A for about 15-minutes and was at 135ºF with none of the external cooling fans running. once I get everything set up, I plan to increase the output in steps and take Flix photos of the alternator from every angle and also check all wires and connections back to and including the battery. That way I can identify any issues before they become problems.
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Nov 21, 2012
651
Yamaha 33 Port Ludlow, WA
Hayden - how is the alternator project coming along? Did have Tuscon Alternator customize your alternator, or was it an off-the-shelf model?

Thanks,

MG
 
Apr 5, 2009
2,911
Catalina '88 C30 tr/bs Oak Harbor, WA
Hayden - how is the alternator project coming along? Did have Tuscon Alternator customize your alternator, or was it an off-the-shelf model?

Thanks,

MG
I have it installed and it is working very well. I am still in the testing phase so have not yet maxed it out. At first I was having problems with belt slippage but that was due to insufficient belt tension. I now have a tension gage and found that I was way under what it should be and have not had any further issues with that. I built a new adjuster bracket that is made from a piece of angle 2x2x¼ which is perpendicular to the pivot which works great. It is much better than the original adjuster bracket and greatly reduces the loads on the mount even though I am pulling more power from the alternator.
As far as I know, all of the alternators that TEA sells are built to spec. You tell them what you want, and they build it in a couple of days, and it is ready for pickup or shipment. The alternator that I got was specified to be external positive field regulated with a power tap for the tachometer. I could have gotten it with powder coating to my choice of colors, but powder coating is a thermal insulator. This would have made it harder for the alternator to get rid of the heat that is generated when producing high amps for the long periods of time required for charging a large LFP bank.
In testing I have had it set at 150A output with the engine at 1,4000rpm for an hour and the case temp was only about 90º C. This was before I got my forced cool fresh air ducting installed. That should cool things down significantly.
Without the forced air cooling, I was seeing a stator winding temperature of 266ºF (130ºC). My understanding is that the Denso hairpin use class H Armature wire which is rated at 180ºC for 20,000-hours (200ºC for 5,000-hours)
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Here is a document that explains the rating system.
essex-furukawa-technical-guideline-nema-magnet-applications-explained-en.pdf (essexfurukawa.com)

 
Nov 21, 2012
651
Yamaha 33 Port Ludlow, WA
@Hayden Watson, thanks for the write-up. Looking good. I agree with not powder coating anything that needs to shed heat. I'm working up a 225-250A alternator with serpentine for a 3 cyl Perkins. Balmar only has a dual-V and I know how much you love them :biggrin:. I am looking elsewhere for this project. Electromaxx might have a pulley kit and the alternator is TBD.

What did you use for the voltage regulator? Did you go with the Arco Zeus?
 
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