Universal M25 front V-belt pulley.

[Hayden Watson]

If anyone with an M25 or M25XP is near their engine, can you measure the outside diameter of the crankshft v-belt pulley? I got a Balmar serpentine belt kit and the drive pulley does not fit and I want to make sure that mine is standard. I measured my wheel as 5.12"ø [130mmø]

 

[Rich Stidger]

That's a good thought @Hayden Watson, strange things can happen. Also, before you drive yourself crazy, why don't you wait and contact Balmar on Monday and see what response they offer. This could be a quick and easy fix.

 

[Hayden Watson]

I am trying to find out if my pulley is the typical size. If it is not, then I am probably going to need to pull the front pulley and have it machined down to fit the Balmar pulley because if I have it turned to a larger ID, there will be very little metal left at the bottom of the grooves. My challenge is that I do not have a running boat and I have the Round Whidbey race on 5/11 and my extended family are leaving on a cruise the day after the race.

 

[Bob S]

Sold my C30 in 2017 and checking my notes it was 5.125 diameter. I think Balmar has made a mistake.

 

[Hayden Watson]

Sold my C30 in 2017 and checking my notes it was 5.125 diameter. I think Balmar has made a mistake.

That is what it is looking like. The Balmar wheel is about 5.044" inside diameter as best as I can measure with my calipers. The balance wheel on the engine is something north of 5.104" after I sanded through the paint. Hopefully they have the correct part and can get it to me quickly. I don't think I can turn the Balmar wheel out to fit because the diameter of the base of the grooves is only 5.328" which would only leave a max of .112" of material if it was a press fit and I do not think would be adequate.

 

[Hayden Watson]

Balmar says that they sent the correct part which is sized to fit over a 128mm pulley but so far all M25XP engines I have been able to get a measurement from are 130mm. Does anyone have a 128mm pulley on their engine?

$450 for a part that does not fit, and their response is "Sucks to be you".

Unbelievable. I know that I will never buy another Balmar part.

 

[kappykaplan]

Unbelievable. I know that I will never buy another Balmar part.

We feel your pain!

 

[Hayden Watson]

balmar says that it is the reseller PKYS problem and PKYS says that it is a balmar problem. Both of them tell me that they will offer me no refund. Buyer beware.

Well looky what I found. Balmar is discontinuing their serpentine belt kits but are still selling their stock in hand. trying to pawn their defective merch off on us is not a good marketing strategy.
Certain Altmount® Kit and Alternator Discontinuations effective May 1, 2024 (pkys.com)

 

[Hayden Watson]

I was able to get the crank balance wheel off and have found a machinist who will cut it down to fit the balmar screwup. It will work but is infuriating that I must shell out another $100 in tools and machine shop fees to fix an error by the manufacturer.

 

[Bob S]

Frustrating experience. Sorry you had to experience this but you’ll be happy when it’s completed. No more belt dust and it runs quieter. The crankshaft pulley is casted and the OD isn’t critical so if Kabota used multiple sources it probably would vary.

 

[Hayden Watson]

Frustrating experience. Sorry you had to experience this but you’ll be happy when it’s completed. No more belt dust and it runs quieter. The crankshaft pulley is casted and the OD isn’t critical so if Kabota used multiple sources it probably would vary.

I know I will be happy with the results. There is no comparison between the performance of a multi-rib belt and the stupidly small 3/8" v-belt it came with.

I beg to differ on the issue of balance, but the front pulleys are critical because they are balanced to each crank so changing the center of mass will affect the harmonics of the engine. On the M25, the pulley / balancer has a large cast counterweight and then there are holes in the casting to correct for each shaft pulley pair.

This is the pulley from your engine. note that it has three adjustment holes.



This is the pulley from Papillon and note that it has four adjustment holes. It is very important that the pulley made for the engine crankshaft remains on that shaft. If you must change pulleys or shaft due to damage, the pulley should be rebalanced to the crank.

 

[Maine Sail]

If anyone with an M25 or M25XP is near their engine, can you measure the outside diameter of the crankshft v-belt pulley? I got a Balmar serpentine belt kit and the drive pulley does not fit and I want to make sure that mine is standard. I measured my wheel as 5.12"ø [130mmø]

M-25's had numerous pulleys from the factory. You need the one with three tapped holes

 

[Hayden Watson]

M-25's had numerous pulleys from the factory. You need the one with three tapped holesView attachment 224329

Thanks Rod. I have the pulley with the tapped holes for a puller. The problem I had with installing the drive pulley was that balmar makes their pulley 128mmø and every pulley on an M25 or M25XP I have gotten a measurement from measures 130mmø so the balmar kit will not fit over the front pulley without being machined down to fit.

I talked with the folks at Marine Smart Energy and confirmed that their M25 drive pulley measures 131mmø which would be a perfect bolt-on fit. balmar and the reseller pkys refused to give a refund stating that 128mmø is within their tolerance so the part is fine even though it is useless without a further outlay of $100 on my part for tools and machine shop.

I guess their "tolerance" is the willingness to suffer the loss of reputation and respect of the boating community as long as they already have your money. As a business owner myself I do not find their business model to be satisfactory.

 

[jssailem]

I talked with Les this evening. He has one of Balmar’s kits. He got the “XP” version crank pulley. Les thinks this means it fits on your pulley because it is milled to tge larger size. And had the 3 holes.

 

[Hayden Watson]

I talked with Les this evening. He has one of Balmar’s kits. He got the “XP” version crank pulley. Les thinks this means it fits on your pulley because it is milled to tge larger size. And had the 3 holes.

balmar does not offer a M25 and a M25XP version (alt least any more if they ever did.) I have measurement from 4 other motors, two of which are M25 and they all have balancers that are ø5.1" / ø130mm. I have found exactly none that have a ø5.0" / ø128mm balancer. I talked with Marine Smart Energy about their kits, and they offer one for the M25 and another for the M25XP and they told me that are the same, but they list them separately so that there is no confusion and with each M25 order they verify that the balancer has the three puller holes because their kit will not work without it.

balmar did not tell me that ø5.0" / ø280mm is the correct size per their drawing, only that it was "within their tolerance."

It sounds to me like what they mean by "within their tolerance" is "We are a big company and already have your money. We can tolerate any amount of pressure you, a mere peon of a customer can apply. Sucks to be you".

My current goal is to reduce their "tolerance" by letting as many future customers as possible know about how they will treat them when stuff does not go according to plan. As they say in the gym, "No pain, no gain." I plan to make their refusal to honor their mistakes very painful. That is why I have included pkys in my rants. The only leverage I have over balmar for their making good on their mistake is for their reseller to fight the battle for me. Their response was "You did not handle the product only with cotton gloves and one of the pulleys has a tiny scratch so we cannot resell the parts so it will not be refunded". That is a direct quote from the pkys tech person on a phone call. Un-flipping believable!

 

[Maine Sail]

We installed quite a few of the Balmar kits on M-25’s there are 5” pulleys. Before we sold an m-25 kit we had the customer send us images and OD of crank via caliper.. Beware Marine Smart energy is Electromaax trying to hide their reputation. we did have to machine down a couple of m25 crank pulleys. Goes with the territory.

 

[Maine Sail]

Ask for Peter Directly.. Who. Did u speak with at Balmar. You want Timm..

balmar does not offer a M25 and a M25XP version (alt least any more if they ever did.) I have measurement from 4 other motors, two of which are M25 and they all have balancers that are ø5.1" / ø130mm. I have found exactly none that have a ø5.0" / ø128mm balancer. I talked with Marine Smart Energy about their kits, and they offer one for the M25 and another for the M25XP and they told me that are the same, but they list them separately so that there is no confusion and with each M25 order they verify that the balancer has the three puller holes because their kit will not work without it.

balmar did not tell me that ø5.0" / ø280mm is the correct size per their drawing, only that it was "within their tolerance."

It sounds to me like what they mean by "within their tolerance" is "We are a big company and already have your money. We can tolerate any amount of pressure you, a mere peon of a customer can apply. Sucks to be you".

My current goal is to reduce their "tolerance" by letting as many future customers as possible know about how they will treat them when stuff does not go according to plan. As they say in the gym, "No pain, no gain." I plan to make their refusal to honor their mistakes very painful. That is why I have included pkys in my rants. The only leverage I have over balmar for their making good on their mistake is for their reseller to fight the battle for me. Their response was "You did not handle the product only with cotton gloves and one of the pulleys has a tiny scratch so we cannot resell the parts so it will not be refunded". That is a direct quote from the pkys tech person on a phone call. Un-flipping believable!

 

[Hayden Watson]

We installed quite a few of the Balmar kits on M-25’s there are 5” pulleys. Before we sold an m-25 kit we had the customer send us images and OD of crank via caliper.. Beware Marine Smart energy is Electromaax trying to hide their reputation. we did have to machine down a couple of m25 crank pulleys. Goes with the territory.

Thanks Rod.

I would have happily provided the OD of my pulley if I had been asked but was not. I said that I had a 1988 M25XP and they told me that I needed a 48-USP-M25 and that will be $480 please. End of conversation. That might be the reason that MSE lists both a kit for the M25 and the M25XP.

On the otherhand, this photo is of a pulley that was made by a forum member, and he told me that the original OD was 5.1". The balancer is clearly stamped D850A KT2 which is an M25 and not an XP. As I said, I have measurements from two M25 and two M25XP and they are all 5.1" / 130mm in diameter.