Anyone installed a Balmar Serpentine belt kit on their Universal M25?

[Hayden Watson]

I am installing a Balmar Serpentine belt kit on my Universal M25XP and the drive pulley on the crankshaft does not fit. It is stamped with the part number 48-AM-306. I am hoping to find someone who has one installed that can tell me if they just supplied the wrong part.

The pulley that I have is too small by 60-thousants.

 

[jssailem]

Too small in the ID?

 

[Hayden Watson]

Too small in the ID?

Yep. It should be a close fit over the factory pulley and bolted to the three puller holes but no way it will go on. To make this work, I would either need to have a machine shop machine the overlay pulley ID bigger or the factory pulley smaller. Both will not be cheap and very frustrating given that the thing cost $450.

 

[jssailem]

Well that’s an odd engineering approach. I would think as the original pulley was a press fit that they would have you remove the pulley and they would engineer the new pulley to the crankshaft. A diameter that would more likely be common for the same engine. Bugger. Hope you get it resolved.

 

[Hayden Watson]

Well that’s an odd engineering approach. I would think as the original pulley was a press fit that they would have you remove the pulley and they would engineer the new pulley to the crankshaft. A diameter that would more likely be common for the same engine. Bugger. Hope you get it resolved.

This approach is not odd and as a professional engineer and former diesel mechanic, I can see no other way to add a serpentine belt to an engine with a v-belt pulley.

It is not so easy as remove and replace. The front pulley on an engine is also called the harmonic balancer and it used to correct imbalances in the crankshaft. The shaft and front pulley are typically spin balanced as a pair and small holes drilled into them to correct any problems. If you remove it, you lose that function. By placing a perfectly symmetrical machined billet aluminum wheel over the original, you maintain the factory balance while adding the new function of the serpentine belt.

 

[Hayden Watson]

Well that’s an odd engineering approach. I would think as the original pulley was a press fit that they would have you remove the pulley and they would engineer the new pulley to the crankshaft. A diameter that would more likely be common for the same engine. Bugger. Hope you get it resolved.

 

[Bob S]

Have you spoken with Balmar? maybe they can exchange it. I installed their kit on my Beneteau and it fit. I made my own kit of pulleys on my C30, same engine. I ended up machining the crankshaft (not easy to remove). I would machine the aluminum pull but it will remove the blue anodize.

Did you do your Electromaax upgrade yet?

Maine, Was wondering if you did the serpentine upgrade yet? No one has come out with a set up for Universals, as far as I know they’re still working on it. There is a lot available for Yanmar, Westerbeke and even Perkins engines. No standardization and every install is slightly different...

forums.sailboatowners.com

 

[Hayden Watson]

Thanks for the link. If Balmar does not have the correct size of adapter, I will end up doing what you did and remove the balance wheel and have it machined down to match the Balmar adapters. It is not just the blue anodizing which would not show because it would be the mating surface. The bigger challenge is that there is very little meat in the land, and I would be worried about it being too thin after it was turned and then I would be totally screwed.
You mentioned that you had all of the dimensions in a notebook. You wouldn't happen to have the original OD of the factory pulley grooves, would you? I am pirating your photo of the back of the balance wheel to illustrate why Balmar cannot supply an entirely new wheel.

@jssailem here is a photo of the back side of the balance wheel I pulled from @Bob S post. There is a lot of stuff going on at the back side. It looks like on these Kubota engines; it is not a dynamic dampener which is unfortunate. They have an inner and outer metal parts which are separated by a rubber bushing which allows a tiny bit of movement to smooth out the harmonics. It would be very beneficial for a 3-cylinder. This one is just a balancer to correct for imbalance in the crank.

 

[jssailem]

There is more going on then was evident in the other images. Fingers crossed that Balmar steps up tomorrow.

 

[Hayden Watson]

There is more going on then was evident in the other images. Fingers crossed that Balmar steps up tomorrow.

Yep, they hide all of the magic on the back side.

 

[Hayden Watson]

I got Balmar's response this morning. "That is what we consider to be the correct part so it sucks to be you."

Unbelievable. Never buy from Balmar. Their stuff is overpriced, and they do not stand behind their obvious screwups.
FWIW, the alternator that I purchased for $350 from Tucson Alternator Exchange has the exact same spec and components as their XT-250 which lists for $1200.

 

[Hayden Watson]

I found a YouTube video of a guy who installed a Balmar kit on a Perkins and had the same problem. In that case, the "Balmar way" was to replace the factory balance wheel with an unmatched new pulley. When he tried to install it, the splined hole to fit over the front end of the crank shaft was too small to fit and when he sent it back to Balmar, they returned it to him with the comment "the size is within our tolerence."
He used a drum sander to "hone out the inside of the splines to fit the shaft to make it work. Within a year, he lost the engine and I just wonder if it was because the new Balmar wheel was not balance to the engine.

 

[Hayden Watson]

balmar knowingly is making as selling serpentine belt kits that do not fit. I found another supplier that tells me that he developed the kits for balmar and then they patented them and basically stole his business. He confirmed that his part is 5.125" ID which is the correct size and will fit and the link is below. If I did not need to throw $480 in the trash, I would have one of his on order now. As it is, I will need to pull the front pulley off my engine and take it to a machine shop for modifications to fit the balmar junk.
PK-M25 Universal M-25 Marine Serpentine Pulley Kit - Marine Smart Energy

 

[Hayden Watson]

Well I was able to have my balancer turned down to fit the balmar pulley for the low, low price of only $137

It turned out great although I sure wish I had gotten the MSE kit which would have been bolt-on.



Here is how it looks after putting everything on the boat.

I was concerned about the original support arm. In addition to being very thin, the angle between the line through the two alternator bolts and the two bolts on the mount is more than 140º and per my geometry textbook, that angle is every obtuse [angle greater than 90º] and so is whoever was stupid enough to think that was a good design! Per the Websters dictionary Obtuse: lacking sharpness or quickness of sensibility or intellect: INSENSITIVE, STUPID) (See red arrows in attach photo) The very short distance on the alternator bracket between the pivot bolt and the anchor for the adjusting arm, greatly increases the loads on the bracket. I have heard of several of the new style brackets breaking and the engineer in me suspects that this is the root cause so given that I am looking to get about double the power out of my alternator than I ever have, it is time for an upgrade.
My new large frame alternator is about 1/2" larger diameter than the old small frame so I must replace the adjuster. What I am doing, it is fabricating a new support structure that attaches to the top side of the motor mount flanges and projects forward to 3/4" behind the belt. To this, I am attaching a Hiem link that will attach to the adjustment anchor on the alternator at 90º and there is nothing obtuse about that! In fact, not it is acute! Now the pivot support arm triangle is pretty close to an equilateral triangle which will put equal force on all three lines and will reduce the load on the bracket to less than 40% of what it was before.

 

[Maine Sail]

balmar knowingly is making as selling serpentine belt kits that do not fit. I found another supplier that tells me that he developed the kits for balmar and then they patented them and basically stole his business. He confirmed that his part is 5.125" ID which is the correct size and will fit and the link is below. If I did not need to throw $480 in the trash, I would have one of his on order now. As it is, I will need to pull the front pulley off my engine and take it to a machine shop for modifications to fit the balmar junk.
PK-M25 Universal M-25 Marine Serpentine Pulley Kit - Marine Smart Energy

John Stevens is flat out Lying to you. He, Electromaax has the worst reputation in the industry and has screwed everyone in the industry, from Balmar, to dealers to suppliers. It is so bad he can't even sell the business. That pulley design was Patent protected well before Balmar even purchased Alt-Mount. Balmar holds that patent now. Electromaax is in patent violation selling those kits into the US and John knows this.He is such a snake that he's has tried to rebrand his company to hide their true reputation. He does not care any more as the company is for sale and he lost his lead engineer, who's actually a good guy to a competitor.

Balmar is selling a kit they designed to fit the engine crank pulley they measured it off of. As I mentioned before that engine had 4 different pulleys that I know of personally.. I Installed 5-6 of those kits that fit perfectly and one kit that needed the crank turned down a few thou. Something that happens with marine engines..

 

[Hayden Watson]

John Stevens is flat out Lying to you. He, Electromaax has the worst reputation in the industry and has screwed everyone in the industry, from Balmar, to dealers to suppliers. It is so bad he can't even sell the business. That pulley design was Patent protected well before Balmar even purchased Alt-Mount. Balmar holds that patent now. Electromaax is in patent violation selling those kits into the US and John knows this.He is such a snake that he's has tried to rebrand his company to hide their true reputation. He does not care any more as the company is for sale and he lost his lead engineer, who's actually a good guy to a competitor.

Balmar is selling a kit they designed to fit the engine crank pulley they measured it off of. As I mentioned before that engine had 4 different pulleys that I know of personally.. I Installed 5-6 of those kits that fit perfectly and one kit that needed the crank turned down a few thou. Something that happens with marine engines..

Thanks Rod. That is good to know.
Balmar could have easily avoided all of this trouble simply by having a note on their web site that states, "ID of drive pulley is ø x.x mm / ø x.x inch. Then the buyer can find out before they purchase the kit if it will work or not. Your experience was that the kits fit but of the five I have access to, they are 2mm short. Had I known of the need to do the machining, I likely would have gotten the kit anyway but would have done it knowing I needed to do some machining and would have planned accordingly.

It sounds like the problem is as you state, there were different balancers and if balmar knows this as I am positive that they must be as you do, they are negligent in not providing the ID of their product to the buyer.

 

[Maine Sail]

Thanks Rod. That is good to know.
Balmar could have easily avoided all of this trouble simply by having a note on their web site that states, "ID of drive pulley is ø x.x mm / ø x.x inch. Then the buyer can find out before they purchase the kit if it will work or not. Your experience was that the kits fit but of the five I have access to, they are 2mm short. Had I known of the need to do the machining, I likely would have gotten the kit anyway but would have done it knowing I needed to do some machining and would have planned accordingly.

It sounds like the problem is as you state, there were different balancers and if balmar knows this as I am positive that they must be as you do, they are negligent in not providing the ID of their product to the buyer.

Before my stroke I was working with Timm & Chris W. To get all this data into a spread-sheet. While I was in the hospital Balmar was sold to Dometic. I have long argued for an all pulley dimensions to be published. Any time you’re buying a kit contact Timm and he can give you the exact dimensions.

 

[Hayden Watson]

Before my stroke I was working with Timm & Chris W. To get all this data into a spread-sheet. While I was in the hospital Balmar was sold to Dometic. I have long argued for an all pulley dimensions to be published. Any time you’re buying a kit contact Timm and he can give you the exact dimensions.

That is very good info.