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Belt problems

RNation

RNation

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St.Peters, MO
I wasn't sure if I should start a new thread for this but I suppose it would be easier to find if anyone else has the same issues.

The problem is my alternator belt stretches fairly quick. I've tightened it so many time I actually stripped the threads in the alternator and had to buy a bolt/washer/nut to use instead. But all the belts I've gotten stretch within a matter of a few weeks. I do buy the autozone and o'reilly belts, maybe that's my problem? Any body have similar problems with a fix?
 
are you single or dual belt? Not sure if it makes much diff tho. Our 84 with dual belts does pretty good for awhile but when one belt goes, usually the alt, it takes the rest of them with it.
 
I've hit the same problems with stretching belts. a standard on lasted maybe a year. the best ones I've found so far are the NAPA premium ones. add 50% to the price tag, buy I've only tightened it once after the first stretch. that was last summer and it's still good to go.
 
OK...I have said this before but here goes again. The problem with the alt belt on these trucks can be blamed on Gates Rubber co. Hmm..What does that mean ?

Well some of you gearheads that have been wrenching back in the 70s and 80s will remember that Gates made 3 main series of belts. The 7 series, 8 series and 9 series.

Now I don't remember the excat specs so if someone wants to correct me feel free but the point is still relavant. These mid 80s early 90s V belt 6.2's were designed to use an 8 series belt.

An 8 series Gates belt was a DAMN good belt and would probably outlast the vehichle it was on as well as two more after it. IIRC I believe it was a 7/16 belt.

Well...Gates a no maka no money with a prodcut that lasts that long and like most companies when they have something that works really well and people want it, they discontinue it.

There explaination was that thier 7 series was beefed up from 3/8 to what ever they made it and could handle the job of both 7 sweries and 8 series applications... WRONG!!!.

The pulleys on the 6.2 become worn after a 100k or so and since most of us get 300+K out of a 6.2 the get worn and the 7 series does NOT sit in the groove properly. Hence the problem.

Gates makes a Hi Performance Belt that is a little stronger and does hold up better.

IIRC PArt # 5725 in Gates. I could be wrong, have not bought one in 10 yrs. (9 series are too thick and do not sit in the grooves right and can jump out. Also check the Balancer Pulley.

Been told by others it can cause a problem as well although I have personally never had one.
 
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Ah ok. I thought you said that one was too thick. Thanks.

So I guess the problem is the cheaper belts just stretch easily from all the diesel vibrations and cheaper material? I thought I was going to have to find a belt with something like a metal band around the inside or something like that.
 
The 57xx is the hi per belt for that Application. The NAPA Belts are nothing but rebadged Gates. even use the gates Numbers with a NAPA prefix.
 
The older trucks with the V belts (6.2 engines) are just plain tough on belts.

If the rig is one you are going to keep, I would start snooping around for a SERP DRIVE setup off of a 92-95 6.5 truck.

You will need to use the water pump, fan and clutch from the 6.5 (turns the opposite way)
You must have all the brackets, the pulleys and such from the 6.5 truck.

The alternator ends up on the Drivers side (slight wire mods) The AC pump used with the Serp setup is the little pancake type and you can use the hose harness from a 91 Burb with the 350 engine (fits right nice)

This mods gets rid of all the belt issues and really cleans up the underhood a bunch.
Gets rid of the AC lines that lay across the top of the shroud too.

unfortunately the old body trucks were never equiped with the serp drive on the 6.2 engine.

I really dont understand why GM did not do it, as all the parts fit right on the rig.

To use the late alternator you must do a little swapping of the Alternator wiring plugs from the newer type rig. (cut the plug off a wreck at the bone yard)

This may seem like a very convoluted way to fix the belt issue but, its well worth the trouble.

The serp drive is smoother and less troublesome by far than the old V belt setup.


Missy
 
I'm double screwed. The only way to convert to serp for me is to convert the truck to 12v and I like my 24v start in the winter. I loosely toyed with the idea of using a series parallel switch from a Mid 70's Mack R model but then remembered how troublesome they were on the Macks. Those Macks sure started good though...wonder if they make an Air starter for a 6.2....:D
 
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