Author Topic: Alternator belt problem  (Read 1804 times)

Offline Chevygold

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Re: Alternator belt problem
« Reply #15 on: December 01, 2022, 04:15:12 AM »
When the power steering pump was driven from the crank via the water pump the belt fouled the bottom hose connection on the block damaging the belt, I think this is due to the short waterpump?
I think it should have a long water pump as when the fan was fitted it was back from the shroud on the radiator but this is how it came to me.
I could shim the alternator and water pump pulleys forward a little but that would put them out of line with the crank pulley, another way around it would be to go serpentine but that's big bucks I think?
Vile, how does a 7448 belt differ from what I have?
Thanks all
Graham

Offline Mike81K10

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Re: Alternator belt problem
« Reply #16 on: December 01, 2022, 10:28:47 AM »
I think VZ said it earlier! Appears you are not using a V belt and that is what you need. The alternator is wrong for your engine as it does not have the V belt pulley as the rest of the engine has (from the pics).
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Offline JohnnyPopper

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Re: Alternator belt problem
« Reply #17 on: December 01, 2022, 10:45:45 AM »
Yeah I have to say pics aren't that helpful, low res. If you got your camera closer I could understand more of whats going on.

Having said that, and I could be wrong, the power steering pump should have a belt that is solo to the crank.

BTW, what is that big hose going toward the manifold from the left (passenger) side?
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Chevygold

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Re: Alternator belt problem
« Reply #18 on: December 01, 2022, 11:25:59 AM »
Alternator V belt is CONTINENTAL 15445MK Mileage Maker as already stated, the one in the picture is badly worn which is why it is sitting so low in the groove.
I didn't try a belt from the crank pulley for the power steering pump, will have to have a look and see if that is possible.
Thinking back it seems my troubles started after taking the power steering pump drive from the water pump.
Hose is the bottom radiator hose to block which is where the belt was fouling on the original set up.
Graham
« Last Edit: December 01, 2022, 11:29:02 AM by Chevygold »

Offline JohnnyPopper

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Re: Alternator belt problem
« Reply #19 on: December 01, 2022, 07:27:55 PM »
The pump has a tension-er on the right side. Look for a cool tool from bd to tighten it  8)

I think you got a bad run on belts or it's a crappy brand. Did you look up VZ's recommendation?
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Online bd

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Re: Alternator belt problem
« Reply #20 on: December 01, 2022, 08:17:35 PM »
I haven't found a belt routing diagram specific to your 1976 C10 SBC.  Nonetheless, after studying the 1976 factory parts books, I believe JohnnyPopper is correct that the P/S pump should be driven directly from the crank pulley using a 7/16" wide v-belt.  A 15/32" wide v-belt is specified by the factory to wrap around the alternator, fan and crank pulleys.  Be sure to use the correct width belts for the greatest bite in the pulley grooves and acceptable durability.  Heavy-duty v-belts should outperform the economy-grade Mileage Marker belt in your pics.  Adjust the belts as previously described or use a gauge.
« Last Edit: December 01, 2022, 08:28:18 PM by bd »
Rich
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In other words... if people learn by making mistakes, by now I should know just about everything!!!
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Online VileZambonie

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Re: Alternator belt problem
« Reply #21 on: December 02, 2022, 09:08:47 AM »
These are images of the correct era pulley belt setup with non-AC truck.
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Offline Chevygold

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Re: Alternator belt problem
« Reply #22 on: December 02, 2022, 11:41:38 AM »
Thanks for everyones help with this one, it was after the mention of the power steering pump drive from the crank that I remembered I'd changed that belt after I found it was rubbing on the bottom hose. In the meantime I had changed both radiator hoses as they were passed their best, I have now fitted the 15445 belt round the crank pulley, power steering pump pulley and water pump pulley and its clear of the bottom hose so all good there.
The alternator now has an AX43 belt round the crank and water pump pulleys, this is a little too wide but I'll run it for now and see how it settles in, hopefully we got to the bottom of the problem and this will help others with belt issues!
Thanks again
Graham

Offline JohnnyPopper

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Re: Alternator belt problem
« Reply #23 on: December 02, 2022, 02:46:06 PM »
Nothing like a dirty SBC, great pics.

So Graham, did you say the belt your running on the alternator is too wide? (couldn't tell from original pics )

That might be your problem, it's being drug into the v of the pulleys.

Notice how the belts are snug in the pics VZ sent? That's what you want.
« Last Edit: December 02, 2022, 03:32:38 PM by JohnnyPopper »
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Chevygold

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Re: Alternator belt problem
« Reply #24 on: December 02, 2022, 03:26:12 PM »
The belt I fitted today on the alternator is an AX43 which is 43" length and 1/2" wide so stands a little proud of the pulley but it'll do for now, water pump pulley is double groove so it has double belt drive so if either alternator or PS pump belt fails I still have drive to the water pump!
Thanks for the pictures Vile, all back to how it was and with the new hoses the belt clears fine, the old hoses must have swollen with age causing the belt to foul.
Thanks again
Graham

Online bd

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Re: Alternator belt problem
« Reply #25 on: December 02, 2022, 03:46:34 PM »
The 1/2" belt is only 1/32" wider than the factory 15/32" width specification.  If you look carefully at the cross-section of a v-belt the angled walls have a short vertical truncation of the sidewalls at the outer diameter of the belt.  When a new belt is slightly proud of its groove (~1 mm), the sidewalls of the belt still effectively make full contact with the pulley groove for maximum bite.  So there should be no worry about that.

Graham, please keep us apprised of the outcome after it accumulates some mileage.  Hopefully, the issue is resolved.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Chevygold

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Re: Alternator belt problem
« Reply #26 on: December 02, 2022, 03:53:03 PM »
Yes BD that's what I figured, will let you know how it goes after a few miles.
Graham