I broke the Fan/alt belt today - what are you using on your car?

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AlV

AlV

Crabs in a barrel
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Well I've been driving the car more and more since getting it on the road.
Today after recently installing an upgraded radiator I went out for a cruise and got on it a few times. Great fun!

The last run of the day I was heading back home I opened it up again and then exited and got to the light half mile from the house. I saw my temp gauge jump from 190 to 210 then 230. The light turned green and I limped home. By the time I got there I was at 260 and puking a bit of coolant. I stop the car popped the hood and damned if I didn't see the alternator belt wrapped around the fan and the power steering belt flipped over.

I got the shop fan going and started to bring the temp down on the car. After a bit I was able to unravel the belt from the fan and realized it was broken not rolled.

It was a new belt from Advanced Auto maybe 150 miles on it.

Which brand and model are you using on your ride? This one needs to be between 48 and 49 inches.
 
I would try a Gates belt, they cost more, but are better. I like the rib style, they bend around the pulleys better, the work is done by the outer part. Make sure you loosen, and properly set tension. Rolling a belt on, can cut life in 1/2 during install.
 
KitCarlson said:
I would try a Gates belt, they cost more, but are better. I like the rib style, they bend around the pulleys better, the work is done by the outer part. Make sure you loosen, and properly set tension. Rolling a belt on, can cut life in 1/2 during install.
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Honestly, I don't mind spending a little extra on the belt. I would hate to see a 20 dollar part take down my engine.
I had a 48013 from advanced auto on there before and won't put another on.
 
Also check pulley alignment. Had a problem with the belt flipping over if I had the A/C on and the motor went over 6,000 rpm and had a sudden deceleration.
 
spl440 said:
Also check pulley alignment. Had a problem with the belt flipping over if I had the A/C on and the motor went over 6,000 rpm and had a sudden deceleration.
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My alignment looks good. Far as I can tell the belt just snapped

image.jpeg
 
Last 340 Dart I had would roll the alt. belt frequently. Pulley alignment was perfect. Was able to get it to roll by just holding it at about 2k. Had some sort of weird harmonic thing going on. Every so often belt would get in this weird vibration...followed by a roll. For the life of me I can't remember what fixed it...
 
Usually when they roll like that, they are too tight.
 
RustyRatRod said:
Usually when they roll like that, they are too tight.
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I'm pretty sure they were tight but I was also able to get good deflection per the service manual. I plan on buying new good year belts and swapping both the steering and fan/alt.

Digging a bit further today I found that while I rotate the pump in the clockwise normal running direction I hear a moan and I can feel the rubber impellers dragging but when I rotate counter clockwise It's guiet with no drag. Can the impeller blades flip? Check out the video

 
I do not think the impellers are rubber. What you hear might be the seal. The noise you hear is friction related due to surface texture. Similar to playing notes on water water glass with finger on rim.

A small spring scale, can be used to apply specified pressure for deflection measurement. Too much belt tension is hard on both water pump and alternator bearings.
 
KitCarlson said:
I do not think the impellers are rubber. What you hear might be the seal. The noise you hear is friction related due to surface texture. Similar to playing notes on water water glass with finger on rim.

A small spring scale, can be used to apply specified pressure for deflection measurement. Too much belt tension is hard on both water pump and alternator bearings.
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Okay, the seal explanation makes sense. I suppose I should put on a new set of belts and make sure o have correct deflection then let her rip.
 
Yep it's pushing water and holding 185 again.

Now I just have to make sure I have correct tension
 
And NAPA Premiums seem to be good as well a Gates. I've raced for years on both.

As for the moan from the water pump, it sounds like the seal. It may be hard with age or dry for some odd reason. Keep an eye on it. If it starts to go, you normally will see coolant weeping from the drain hole on the underside of the pump snout.
 
Gates or Dayco are the only good belts. The off brands are only good for 50 miles or 50 minutes…..
 
doogievlg said:
Super old post but do you recall the part number?
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Part number of the belt? It was a gates 7480 XL. If I remember correctly I also added a washer between the sleeve bushing and the alternator bracket which stopped the vibration that I believe was causing the belt to jump at hard acceleration.
 
AlV said:
Part number of the belt? It was a gates 7480 XL. If I remember correctly I also added a washer between the sleeve bushing and the alternator bracket which stopped the vibration that I believe was causing the belt to jump at hard acceleration.
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Thanks
 
I still use the washer today and after adding it and changing the belt to gates had no problems since this posts 2016.. JINX!
 
You can get original style belts that fit (and aren't full of little divits) from Quanta Products - same people that make new gas tanks for old cars.

Located in Rising Sun MD (near Cecil County Drag-A-Way - Traction Capital of the East!!!). (410)658-5700
 
I have 2 on the Water pump, using 1966 273 ac pulleys... car don't run no more than 185 in the middle of summer in Tampa. And yeah I had the same thing happen you did first time I took my car out and nailed it. The kicker is evidently they didn't make a belt for my exact size so I have to use a universal belt for an air compressor to go from the alternator to the water pump to the crank the other one goes from the crank to the water pump to the power steering I like having two on there it's cheap insurance I'll tell you what those aftermarket Universal belts suck
 
Shop that built my engine really likes Dayco Top Cog belts. I think the number was 15440 but not 100%.
15 is .440 width, then your length-440 = 44" such a 15460= 46" , add a 5 for 1/2" increments 15, 15465 = 46.5" and so on
 
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