I keep throwing a fan belt

Hello: You mentioned it is 1982 which to me indicates V belts. You are also going around 4 pulleys and probably 100 amp alternator. I ran into similar situation where the belt was only in contact at best with 30% OF THE PULLEY surface. That requires a rather tight belt to not slip. I was using Delco top cog belts and they would roll over in the pulleys in no time. The Goodyear Gatorback stood up much better. Do they still exist I'm not sure but were the best for me.

I would bypass the smog pump. If there was melted rubber on the pulley, it will do it again. I have an '84 454 with no smog pump. It makes for a really long run from the crank to the alternator, but if you keep the belt (very) tight it will hold up.

All that being said, when I first put the engine in the rig it was shredding that belt. It was an alignment problem. Sounds like that might not be your issue but if it keeps doing it I would look into alignment.

Years ago, I had a Southwind with a 454 that regularly ate fan belts. I could either set it too tight,which caused the belt to break in a short time, or too loose, which caused it to slip and the battery to go flat as the alternator was slipping. I bought a belt tension gage and finally got the belt to last for a years worth of driving (about 7k miles). Mine was an '83 and shortly after Chevy went to a double belt configuration. A single belt was simply marginal when driving the alternator, AC, water and air pump.

The other issue with that engine was that it regularly went through spark plug wires. Finally went with NAPA lifetime wires and replaced them almost annually. Routing was critical to keep them from crore-firing. If a wire from a firing cylinder was routed next to a wire from a cylinder in intake cycle I got "sneezing" where the Intaking cylinder was fired. This occurred under full throttle.

Dick L '04 HR Imperial

Well, I fixed it for now. Much thanks for all the advice and general input.

Medium story short:
I took off the smog pump pulley and cleaned off the rubber melted onto it with a propane torch, a putty knife, a wire brush and a final cleanup with acetone. It was pretty clean looking when I got done. I (gently) put it in a vice to hold it. I put the original length belt back on it. Drove it at night for two hours with several stops and shut downs without a failure.

Long version:
I keep the RV at a friends house and I was supposed to meet him at his place at 5pm or so to put it away. I started working on the belt at 3pm. I was having a tough time trying to clean it while on the engine. I recalled someone somewhere saying it was pretty easy to take off the pulley so I went for it. Three bolts but none of my standard wrenches fit. Trip back to the garage to get my metric set. Just like someone had said, 10mm fit. D**n pully was spinning like crazy so I put the belt on and tightened it to hold the pulley. A few minutes later I had it off without dropping one bolt. (Small victories)

I tried to us a utility knife on it while holding it by hand when I got this clear picture in my mind of the knife slipping into my hand. I took it in the garage and put it in the vice. My propane torch is in a drawer right there next to the vice So, per a recommendation I found on the web, I gave it a try. Took a couple of minutes with the heat to get the bulk of the rubber off with a putty knife and then a few minutes more with a wire brush to get it really clean. A wipe down in the grove with some acetone and it looked pretty good. It even shined when I had it back on the pump and the flashlight was on it.

Back in the RV I spun the pump so a bolt hole was on the very top and then aligned a hole on the pulley with that hole. Got it the first time! A few minutes later and it was finger tight. I threw on the belt again and started the engine. No squeak and it did fall off after a couple of revs. Dog house cover on and I was on the road. (No cleanup if I was going to get there by 5pm)

I left the house at exactly 4pm. One stop on the way to get a fancy replacement belt I had ordered and another stop for an errand for my wife. WHERE THE HECK DID ALL THIS TRAFFIC COME FROM?! I haven't mentioned that I get flex time at my job so I don't normally travel during regular commute times and I normally commute against the normal traffic flow. That and working from home sometimes leaves me unaware of just how many cars normal people have to put up with.

Half an hour later I'm about six or seven miles down the road. I'd heard a squeak or two that eventually turned into a regular repeating squeak squeak squeak. (Those paying attention know what this is) The bolts on the pulley were only finger tight. I had forgotten to tighten them after putting on the belt. I pulled off on a wide shoulder and got to doing that. It is amazing how fast things get hot in an engine bay. The smog pump pulley wasn't that hot but the one on the alternator left red marks on my arm. A few minutes later and I'm back in traffic.

I skipped the pickup of the fancy (read $27 vs. $7) belt in hopes I could make the pickup for the wife. I made the wife's pickup just in time and finally made it to my friends house at 6:03pm.

I'm going to try and figure out how long of a belt to get for bypassing the smog pump and put one of those and another full length spare in the trunk. That and I will start bringing my metric tools with me when we take it out.

Clicky Nuff said...:)....Dennis

Lots of good advice to checkout! I had this happen to me once in a car and I had a broken motor mount!

kaz442 has a good point. The smog pump may be dragging when it gets hot. Do all the pulleys have melted belt residue? I would bet red schotchbright and asatone will remove the residue. Look at all the suggested answers. One more thing make shure the belt is tight if it can slip under load you will have problems. You can find instructions on how to and how tight.
Now I am assuming this is a single belt drive not a serpentine belt to the alternator and smog pump. I would clean all the old residue off the pulleys. Make them shine. Now when you tighten the belt make shure it is tight enough that you can turn over the engine by turning the nut on the alternator. Make shure you have the right belt and it fits down in the pulleys.
Make shure the bolts that hold the alternator after you tighten it are in good shape and don't come loose. I am still suspisch of the smog pump. Do you have a laser thermometer? Check the temperature of the smog pump after you have run for a little while or if the belt fails again. There is a reason they went to a two belt pulley system later.
Bill

Also you may want to look for a cracked pulley on the water pump and the crankshaft. If cracked they will throw a belt.

You stated a build up of melted rubber on the air pump pully. Sounds like the air pump is seizing up when it gets hot. Try bypassing it with a shorter belt.

It could be that the harmonic balancer on the crank shaft is shifting and causing belt misalignment.