Serpentine Pulley Kit For M-25's - Any Interest?

[mainesail]

Hi All,

I am working with a company called Electromaax to try and source a serpentine belt kit for the Universal M-25 & M-25 XPB diesel's. Electromaax builds high quality heavy duty alternators, wind gens and water makers and also has serpentine kits for many engines, but as of yet, not the M-25 or M-25 XPB.

This kit would drastically limit belt dusting and allow significantly larger alts for those with banks that can take the current, like AGM or GEL battery owners.

As many of you M-25 owners know the factory belt is really limited to 80-85 +/- amps due to the belt size and with a serpentine kit an alt of 160 amps or more is possible. If you have AGM's or a large bank of wets this means a LOT less engine run time to replenish the Ah's used. Even a bank of four flooded T-105's can take more current than you can produce with the stock belt on an M-25.

Electromaax is willing to manufacture this kit, though they are not completely in-expensive, but they are looking for feedback as to who might want one before spending the time to design them and manufacture them..
If you have interest in a serpentine kit for an M-25 please email John at:

jstevens AT electromaax DOT com

http://www.electromaax.com/

Kit would look something like this:

[Ron Hill]

Main : I see that the serpentine belt would have some advantage, but I'm not too sure I'd spring for that modification.
1.  You better get at least 2 belts, because if the belt needed to be replaced (for what ever the reason) I don't believe that you are going to any a local store for a replacement.
2.  Most 3/8"--7/16" belts will handle up to 80 - 90 amps charging.  I'm not too sure that your little 21/ 23hp engines or your batteries should be charging/recharging at a higher amperage than that.
3.  Most of us that have replacement alternators (hi-output) have had the lateral alignment problem and have gotten "close" but not exact - with minimal "belt dust".  Not too sure how close the serpentine belt needs? 

A few things to think about before signing up. 

[mainesail]

Ron,

I install quite a fair number of alternator upgrades and have done a number of serpentine kits. I've done them on Yanmar's and Perkins. There is no comparison between a serp kit and a single belt....

I would just like the option as I have a fair number of M-25/AGM customers who have the field voltage limited to use the stock belt. This is more for the customer with AGM's than wets. An M-25 can easily handle a lot more than 100 amps with the right belt though if in bulk you'd want to have a field cut switch so you'd have more available hp to the prop if needed..

[Ken Juul]

Looking at the web site, some of the kits come with a new water pump, some not. But lets assume no water pump for the M25.  The average price for a ribbed belt in the auto market is $5 a foot.  But most of them are 6 ribs, so lets say $7/ft for the 10 rib belt they supply.  Thats about $28 for the belt.  A machined pulley should run about $40 for the small and maybe $80 for the big. 40+40+80+28=188.  The average price of the sets are $600, that is roughly a $412 profit per set.  Might be a great upgrade, but in my opinion way over priced.

[Ron Hill]

Guys : All I was trying to point out is that I can't comprehend why anyone needs to charge at more than 80/90 amps!?!

Then take the cost pointed out by Ken.  I also believe that alignment could be a problem for the normal "do-it-yourselfer"!

Just take into consideration my/Ken's thoughts before going to the serpentine belt change out!!

You also need to make sure there is clearance between the pullys and the engine overhead piece as well as the steps!!

As Stu says "your boat, your choice".  

[mainesail]

Because I have a number of my customers who have invested heavily into AGM's to "charge faster" and they don't want to run the motor for hours on end to do so. They can't take advantage of the fast acceptance of AGM batteries with an 80A alt.

Their are lots of things that cost lots of money for sailboats that should not. Why does a 6" plotter cost more than a computer or a 50" TV or a refrigerator, volume I guess? I can buy my same Westerbeke/Mitsubishi base engine from an industrial supplier for about 50% less than I can buy it from Westerbeke but I can't buy a serpentine kit for an M-25 anywhere that I have been able to find and my customers are more than willing to pay for it.

At this point no one is making these pulleys for an M-25 this means small volume production which usually means higher cost. When you consider what some of my customers paid for their battery bank $500.00-$600.00 for a serpentine kit seems pretty cheap.. There are many out there who over paid for Balmar's too...

I was just asking if anyone is interested. I currently have two customers who want/need a serp kit but can't get one.

My customer with the Perkins is putting in about 175 +/- amps in during bulk into a 500 Ah AGM bank. They can get back their previous days use in about 20-25 minutes. They like to sail not motor so this is great for them.

This kit is not for everyone but it may be for someone....

[Stu Jackson]

There's a real lack of clearance between the crankshaft pulley and the inside end of the bottom set of companionway stairs on our C34 with the M25 engine.  I'm not sure if a deeper pulley would fit without some physical modification of the wooden stairway section.

What do owners of M25 series engines think?

[Fuzzy]

Stu:  I also wondered about the clearance.  I would like to get serpentine belt system also.  Katarina has a 100amp Balmar
and (4) golf cart batteries for about 440ah. I get quite abit of belt slipping (squeling) with my 3/8" belt.
Larry

[mainesail]

Just an update. Since I posted this John has had a great response with lots of interest and is going to produce a kit for the M-25's. It may take a month or two but Electromaax will have them. They are really welld esigned and simple to install as the pulley kits simply fit over your existing pulleys. I have an install I am doing in August and will take some pics.