No response in Tech (Driving belt torque)

SubaSteevo · #1 11-25-2002, 02:18 PM

Just went to NAPA to get a new ps/driving belt because my old one was starting to crack and made squeaks when just starting. The repair manual says to torque the belt to 143-176 lb using a tension gauge (if I'm reading it correctly)...there's the problem. 1. I don't own a tension gauge, 2. I don't even know what one would look like if I saw it, 3. The guy from NAPA said I didn't NEED TO torque the belt. So I ask you, does a tension gauge exist? what does it look like? do I need it? if so, where can I get one? I'm looking to do the belt today, so any help would be greatly appreciated.

P.S. Could this tension be the torque of the slider bolt that adjusts the belt and not of the belt itself?

Mr. Pockets · #2 11-25-2002, 03:23 PM

I think you hit it right there, man, I think that, using a torque wrench, you want to apply torque to the adjuster and lock it down at the specified number.

I am trying to remember how the tension adjuster works. I think it's an arm with a bolt head fixed to it in the middle, and then a bolt at the other end of the arm that slides through a channel and locks it in place. I think that your manual is referring to the torque you're supposed to apply to that tension arm - definitely not the locking bolt.

I hope that this helps. Sorry nobody answered your post in the Tech Q&A forum. I didn't see it.

SubaSteevo · #3 11-25-2002, 03:35 PM

Thanks a lot. That's what I was thinking too, just wanted to get a second opinion before I tried it.

#4 11-25-2002, 03:36 PM

There is a good picture in bottom of the how-to locker under "swapping the alternator". As for the belt tension it should deflect .2 inches under 22 lbs pressure applied on the longest belt run per the manual. (real tight)

Beav · #5 11-25-2002, 03:46 PM

It took a bit of looking but I found a couple pics of a belt tension gauge (mechanical) for you. http://www.powerstore.cummins.com/repair_example.htm (first and third items)

Now mind you that most techs don't own one, have never seen one and probably more than a few don't even know that such a critter exists. They're pricey, I think in three years of selling MAC Tools I sold *one* and I think it was around $175. There's also a couple electronic ones available for around $400 and up.

Here's the clue and catch. Tight enough to not slip and not so tight as to ruin the belt, the bearings of the alternator, water pump, p/s pump, a/c compressor, idlers, etc. Hope that helps.

BTW - No, they are not referring to the bolt. That much torque would snap that little bolt long before you came close to 175#.

Mr. Pockets · #6 11-25-2002, 04:00 PM

Thanks for the correction, Beav. I suppose that 175 pounds of torque should have sounded like an awful lot to me.

I have never used a belt tension gauge. If the belt squeals after I install it, I tighten it until it doesn't squeal any more.

SubaSteevo · #7 11-25-2002, 05:48 PM

Figured out that was way too much torque before you guys even said anything (don't know what I was thinking). So I put the belt on and tightened it to what I thought it should be like (it moves slightly when I push on it but does not fly off or squeal while driving). Thanks for all the help, the people on this board are the best.