Fan belts

[militarypotts]

I run the stock 230ci Tornado motor in my truck. My question is, currently I have two belts on the truck. Should I get the 3rd one and install it, and if so does anyone know what size? I think I'm correct when I say the three belts were there as back-ups for each other, but I may be wrong.

[Barrman]

The 24 volt alternator needs 2 belts to turn. Better would be 3. The M35 whistler only has 2 for the alternator. I put a brand new matched pair on and it took me several attempts to get them tight enough to not squel upon start up each morning.

My M35 Gasser with the same alternator has 3 belts and no troubles.

The fun with the M715 is the weak water pump bearings. They will wear out very fast if you have two belts on there super tight. I would suggest getting the fattest belts you can and as many as you can fit on there. Then set them as loose as possible to let the water pump live longer.

I don't know the number for the stock belts. I would suggest pulling on, taking it to an auto parts store and matching it up exactly. Width is very important for them to work right with the high load the alternator puts on them.

[ELB]

My M715 has a Gates 8419 extra service (458k) belts on it. They was on it when I bought the truck so I do not know where they came from. Hope this is some help.

[militarypotts]

My M715 has a Gates 8419 extra service (458k) belts on it. They was on it when I bought the truck so I do not know where they came from. Hope this is some help.

It is a help, thank you. I will go out and check my two belts that are on the truck now. I guess NAPA would be a good place to start. Would you know the tension needed, or just leave it where it is now? I've never thrown a belt, so I presume the tension is correct right where it's at. I will get around to this project shortly, as my mom was taken to the hospital this morning. She's 88 with fully failing kidneys. Thanks again for the info.

[97XJSP]

I haven't checked the manual to see if there is a tension spec for the belts or not. I know the newer serpentine setups have a certain recommended tension and there are tools for checking the tension.
My "scientific" method for setting belt tension is to start pretty loose and tighten it up in small increments until the belt doesn't slip anymore. That way I know for sure it isn't too tight, which as Tim mentioned can be pretty hard on bearings and components...
I hope everything goes ok with your mother.

[wolf.dose]

First: Todays belt can carry much more kW than the belts of the late 60's.
Second: For that case you have to use the Gates series of belts which is made for exact equal lenght, even under load. If they are available in Germany, they should be available in the US.
Third: With nowadays belts for a 60 AMP Gen one belt should be sufficiant (60 x 24 is 1440 Watts max. Including for may be 1 to 2 HP of the water pump, one belt sould be sufficiant, for today they can transmit up to 5 kW.
Fourth: A properly rebuilt water pump should comprize up to date bearings, so 3 to 4 kW should not be the problem.
If you use chinese or somewere made scrap bearings for rebuilding (Proparely as cheap as possible), it is not my ...
Wolf
I once had OE bearings, however, found out, they are scrap. Bought the same number bearing of a quality maker (5 times as expensive), no more problems!
I can give you the bearing number, if interested!

[N2S3]

Please let me know the Gates No, one of three belts runs loosely. In the engine compartment lives the Original Tornado.
Would be pleased if you describe the bearings too or tell the Part-No and where to buy them. My WP needs some attention.
Living in Germany as well, so your experience is welcome.

[militarypotts]

Actually I went out and checked my belts, and their's 3 of them on the truck. Can't figure out why I thought their was only two on. Must be that age thing we were talking about in another thread.