Serpentine Belt Upgrade

[jviss]

Finally, finally did this. I had wanted to do it on the Catalina 36 but it never made it to the top of the budget list. Now it's done on my Tartan 3800.

Balmar AltMount Serpentine Pulley Kit.

Bottom line: I had a squealing belt and lots of belt dust with my 125A Ample Power alternator driving a low 230Ah bank. Had to back off the engine speed when bulking up, limiting me to about 45A bulk charge. I think I also had belt slippage, as evidenced by a shaky tach. Now I have a solid connection, and bulk at 100A, tach is fine, no dust.

It was not as easy as I had imagined, not so much a "kit" as a collection of parts that will get you on your way, but it's 99% done and working. I had to source parts that should have been included, or "covered;" and issues remain to be resolved.

It is so choice. If you have the means, I highly recommend picking one up.

Detailed review to follow.

 

[Mark Maulden]

How high in rpm do you have to go for max alternator output with low batts? I'm going through all this with Beta concerning oil upchuck from my new saildrive while charging in neutral. I was surprised I have to get to ~1800 rpm using a Balmar 120a alternator. We are going down in pulley size. The only other concern I might see is not much belt area contact with the water pump pulley. Not to criticize your installation. Just something to track over time. Looks good and has to be a definite improvement!

 

[jviss]

Thanks, yes, the water pump pulley doesn't have much belt contact, but it was that way with the V-belt, too, and it seems to work just fine.

For 100A on a low bank I need about 1,800 RPM.

 

[jviss]

I did some research on my batteries, a main bank of two SCS200 115Ah (20 hour rating) flooded lead acid units. The recommended maximum charge current is 13%C, so 30A. With theses in parallel I should limit to 60A, I guess, and run the engine fast enough so the regulator is still regulating, and additional loads are handled without decreasing charging current. But for 60A I can probably run at about 1,500 RPM maybe even less.

Make sense?

BTW, once in accept mode I can maintain 14.8V at much lower RPMs than bulk initially requires.

 

[jviss]

I have Freedom 10 Inverter Charger, a Link 2000 controller, and the Link 2000-R Ideal Regulator Option. I looked in the manual, and while it seems I can set a limit for alternator output, I can't find a way to limit the battery charging current only. If I limit the alternator, I will be using the output for charging and for loads, so slowing down from maximum charge current.

As it is, I just started charging; the bank was at 12.25V with a 12A load, so probably around 12.4V at rest, or 72% SOC. I fired up the engine and once the alternator came on it kinda stumbles at the 700 RPM idle. I upped it to 1000 RPM, and I'm putting 68A into the bank. I wish I could program the system to clamp the charging current at 60A, but let the alternator put out enough to cover the loads in addition.

Maybe a battery temperature probe would improve things?

 

[Mark Maulden]

How about limiting it to ~110a and adding the battery and alternator temp sensing? I never let an alternator hit its absolute max output. Just a “thing” I have..

 

[jviss]

I have a 125A alternator. It's currently limited to 100A max. by the Link 2000-R. I think battery temp sensing would be a good idea. I have to research to see if my system can regulate according to that.

 

[LeslieTroyer]

My problem with the Balmar bel is I would need new alternators, making the price way more than I like.

 

[jviss]

My problem with the Balmar bel is I would need new alternators, making the price way more than I like.

Why would you need new alternators?

 

[LeslieTroyer]

They offer a pulley that fits my LN shaft diameter.

 

[jviss]

Do you mean they don't? What's the shaft diameter of yours?

 

[Mark Maulden]

Les, you can find pulleys online..Balmar suggested to me to try Mack Boring

 

[LeslieTroyer]

I’m thinking of doing a gilmer belt system.

 

[LeslieTroyer]

Do you mean they don't? What's the shaft diameter of yours?

Yes that is what I meant. 5/8 IIRC

 

[Mark Maulden]

Why?

 

[jviss]

That's 15.875mm. One could very easily make a spacer to bring it out to the "standard" 17mm.

(Let me know if you get serious about this, I can make the spacers for you on my lathe.)

 

[jviss]

Update. So, despite the fact that I tightened my alternator pulley with an electric impact wrench (perhaps too wimpy), my pulley is chirping - making a high pitched chirp, only occasionally, and not for long, on startup with a depleted house bank. The nut's not tight enough.

I have a toque wrench, but no effective way of holding the alternator shaft or pulley while I try to torque it.

There's a hex recess in the end of the shaft, but it's blocked by the torque wrench socket, of course.

I don't think I can use an open end or box wrench on this, as it's well recessed in the pulley.

There ARE special wrenches for this purpose, like a claw-foot socket wrench, but I can't find one for 15/16"; found several in 7/8".

I've also looked for a 15/16" socket that has a hex on the top, like some spark plug sockets, but no luck.

Can anyone help me on this, in referring me to a source for this part, or another method of tightening it?

(I might just have to make something.)

Thanks,

jv

 

[LeslieTroyer]

I use an air impact and the alternator shops ive been in use air. So I suspect your correct in a wimpy electric wrench.

On another note I talked to Balmar, and asked about the crank pulley mount. Seems their M25 kit doesn’t work on my year off engine.

 

[jibes138]

Will a strap wrench hold the pulley tight enough to allow you to crank on the nut? Worth a try if you have one. The farther out from center the less force you need to resist the torque of the socket wrench.

 

[jviss]

Thanks, all. My intuition is that a strap wrench won't be strong enough for this. I'm going to find or make a crow's foot socket so I can reach through with a hex key for the shaft.

I missed a call from my local NAPA store who I had asked about this, so maybe they found one.

jv