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I have a Wagoneer(ya a Jeep Wagonner) with a 78 351M in it. I have a sag power steering pump on it with a double pulley. The waterpump belt also drives the power steering. When I rev the engine fast, the fan belt squeels. Belt doesn't do it with the fan removed from the water pump. So I need a double belt over the water pump. Any stock configuration I can use for this? I'd need a new crank and water pump pulley.
Or add a idler pulley? Is it even possible to run a v belt on the flat side? Something like this.
If yours is like mine the water pump pulley runs off the back sheave on the crank pulley, and that is what it looks like in the pic. If that's the case I don't think you will find a crank pulley that will work as you must have both sheaves you are using exactly the same diameter, and the many pulleys I've looked at all have those two sheaves as different diameters. (I've looked at a lot of pulleys as I'm going to run two belts to my alternator and finally found that mid 80's 302 crank pulleys have the front two sheaves the same diameter.)
As for an idler, yes you can do that. In fact I'm going to do that on my alternator's second belt. And I'm using the standard A/C idler pulley bracket from an 80's 351M/400 but have changes to V-pulley out for a flat serpentine pulley. I can provide a link to where I detailed that if you want.
But, unless you are running a fan without a clutch I don't see why the belt won't handle the load. So if you don't have a fan clutch you should. If you do, make sure the belt is the right width - it should lay down in the pulley almost flush. And, if that doesn't work you might try a trick my father taught me - take a round file/rasp and lay it in the groove of the pulley and tap it with a mallet hard enough to leave little "teeth". Do that all the way around on all three pulleys and that will provide a lot more grip - but doesn't chew up the belt.
If yours is like mine the water pump pulley runs off the back sheave on the crank pulley, and that is what it looks like in the pic. If that's the case I don't think you will find a crank pulley that will work as you must have both sheaves you are using exactly the same diameter, and the many pulleys I've looked at all have those two sheaves as different diameters. (I've looked at a lot of pulleys as I'm going to run two belts to my alternator and finally found that mid 80's 302 crank pulleys have the front two sheaves the same diameter.)
As for an idler, yes you can do that. In fact I'm going to do that on my alternator's second belt. And I'm using the standard A/C idler pulley bracket from an 80's 351M/400 but have changes to V-pulley out for a flat serpentine pulley. I can provide a link to where I detailed that if you want.
But, unless you are running a fan without a clutch I don't see why the belt won't handle the load. So if you don't have a fan clutch you should. If you do, make sure the belt is the right width - it should lay down in the pulley almost flush. And, if that doesn't work you might try a trick my father taught me - take a round file/rasp and lay it in the groove of the pulley and tap it with a mallet hard enough to leave little "teeth". Do that all the way around on all three pulleys and that will provide a lot more grip - but doesn't chew up the belt.
That's exactly what I'm doing. It's a off road rig, and I want maximum air flow at all RPMs. If needed I can always do electric fans, but wanted to stay away from them right now. That file idea sounds like a good idea to me!
If that doesn't work and you consider the dual-belt arrangement you will have to either find a crank pulley with the back two sheaves of the same size or move the belts to the front two sheaves and space the water pump pulley and the P/S pump forward to accept them. And then use the idler. Here's how I'm doing my dual belts to the alternator. As you can see I'm using the stock A/C bracket to hold the idler pulley.
And here's the idler itself. That bracket and spacer are the stock 351M A/C idler pulley bracket, although the pulley was supposed to run on the vee side of the belt. And the flat pulley comes from a 460 w/a serpentine system. Turns out the bolt going through the ID of the original pulley's bearing is the right size for the flat pulley's bearing ID. The only things I did were to grind the bolt down just a bit so it doesn't poke through the back of the bracket and hit the A/C bracket, and to put a set screw in the spacer so I could prevent the bolt from backing out.
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. I'd put the idler pulley between the crank pulley and water pump pulley (on the alternator side)... because the belt span from water pump to power steering pump has high tension on it... can also try some 'belt dressing' to reduce squeal (especially on an old dry belt)... make sure belt is wide enough to not be riding on the very bottom of the pulley grooves... Tractor Supply carries several flat pulleys with ball bearing...
Seems to be good. It has prob 75- 100% more belt contact on the water pump than before. I can rev from idle to 6 grand without hearing a peap from the belt.
08-17-2014, 10:04 PM
