So i have a 283 chevy motor. Pretty hopped up. Single V belt driving water pump and alternator. Just replaced the belt because the old one finally gave up. Got on the freeway today, and side-stepped the clutch at about 45 in first to "clear it out" well on the way home i noticed it was running a bit hot. Popped the hood and the V part of the belt is sticking up, while the back part of the belt is in the pully. Whats causing this? pullys are pretty well aligned. Motor revs to about 7k.
Probably the wrong width of belt. It should fit nicely down into the groove. I have also stopped buying belts from discount stores, the worst I ever had were Pirellis, they would stretch and wear out real quick. Don
Common problem back in the day. Corvettes used deep groove pulleys all around. I found that only the generator pulley needed to be deep groove. Somebody stole my gen some years ago and there went my vett pulley.
Check your belt alignment. Sounds like the belt is being rolled on the pulley. Especially check the balancer first.
Could be improper tension, either too tight or too loose. Could be wrong width or belt type. Could be a bad cord in that belt. Pulleys might be gauled, pitted or rusty. Harmonic balancer might be "walking" at high RPM. Replace the belt, once it has flipped it'll keep doing it even if you fix the underlying problem.
I got a non HAMB aged Malibu with a built 350, had the same problem...At high rpm.. Switched to a deeper alternator pulley and she hasn't flew off yet... If it worries you, any alternator shop can hook you up with a deeper pulley for cheap..
Belt too tight. Back n... 69... some Army buds and I were coming back from Paris in a friends bug, which ate it's gen pulley and belt at O-dark-30. We had a spare pulley, but no replacement belt. Luck and grace from above dealt us a FINA station in Verdun that was open. Being a Nationalistic garage owner, he had Simca, Renaut and Citroen belts, but nothing for bugs. He found us a cast off belt and it fit so tightly we had to push start the car. When we reved up the motor to charge the battery, it flipped to one side of the V. We made it all the way north, back up to Kaiserslautern, before the belt came off. But we made formation on time and didn't get an Article 15 for being AWOL in France! Gary
Used to have that problem back in the day. Belts would stretch at high RPM, a deeper alternator pully helps, also you can make a tab up off the adjuster mounting bolt to keep the belt on.
This will sound crazy but try a used (seasoned) belt. I have an engine that spits new belts off as soon as I rev it. peace
This used to be more common in high RPM use. The belts were reinforced by nylon cords down in the V, heavier than the rubber and the belt would flip over by centrifugal force at high RPM. So they made the belts with the cords in a flat band around the outside. Check your pulley alignment, if they are all in line maybe you just got a bad belt.
Did this happen just once or does it continue to happen? I ask because..... I put a new water pump on my Corvette and by the time it was done I was working in the dark, kinda by feel. Apparently I had the belt twisted, nicely seated in the pulleys I could see, but flipped on the crank. Closed the hood, drove it a bit, checking for leaks. When I opened the hood a few days later, the belt had completely flipped to the wrong side on all pulleys.......Just a thought.
I had this on a 67 b,cuda w/440 and when i went to the drags to race the belt flipped on every round,the car was auto and was warned about my belt on the track,not broke.So i made a screw clamp that bolted to alt adjustment and caught the belt.I tried new and any belt i could get and same thing every round.If my pullys wert perfect they were very close.Told new owner about it and he said no problem,then called me on what i did or didnt do,street driveing ok ,hi rpms flip.. ......................YG (Only had one belt)
That happens occasionally to the 283 in my '31 Ford. I've replaced the belt a couple times, still happens.
I think even the slightest amount of runnout on any of the pullies will cause problems at high rpms. This is one good reason for under drive pulleys. Im not buying into the so called HP gain, but the reduced belt speedwill keep you from pitching belts.
Belt too wide for the alt. pulley. Belt to tight. Pulleys out of alignment. Do you have a multi groove pulley on the crank and the belt is in the wrong groove? Or combination of above. Once it flips you need to replace the belt.
I had this problem on one of my vehicles in the past, and switched to a firmer belt, and it cured it for me. You should be able to match the size to a belt from a lawn and garden supplier, it does not stretch as much as a conventional belt either.
Old stock car trick. Try a top cog belt. Regular V belts seem prone to flipping over @ high RPM. We have never had a top cog belt flip over on us in many seasons and billions of revolutions. For whatever reason the belts with the "cogs" on the outside of the belt (think an inside out blower belt) seem to make them immune to the high RPM flip. http://www.dayco.com.au/products.aspx
"Back in the day" this was an almost universal problem, and one of the belt manufacturers came out with a belt that had all the heavy mass towards the outside. It mostly stopped the problem, but I forget the brand of belt. It had a black and white "checkered flag" pattern on the outer face. Somebody help me out on this, was it the "Dayco" belt? Dave
was common back in the day with high winding 283's, 327's etc. Had a 56 with a 327 that did it every time I went thru the traps--finally doubled the top gen arm (two welded together) and made a stud off of it as 39 Ford stated--no more issues
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