351w V-belts

[triracer67]

1967 Bronco with 1969 351w, stock bronco power steering pump and alternator. One belt runs completely around the four pulleys, alternator runs to water pump and crank. I'm trying to replace belts and they have no numbers. Local parts store doesn't have ability to measure, only willing to look in computer and get me belts that don't work. Anyone run same set up and have belt numbers? I'm trying to find a parts store to measure belts, but, numbers would be nice. Thanks, rob

 

[Broncobowsher]

one belt, four pulleys. That is not stock. V-belt only runs 2 or 3 pulleys. That's it.
Someone rigged that one. No one is going to have a part number for that bastard.

You mention belts, as in plural, and the description kinda hints toward a normal crank/water pump/alternator routing. So it is a bit of a mystery what you are running.

The alternator belt (not the one on the power steering as well) might be a stock bronco belt. Depends on what brackets were used during the install. If it has the retrofit adaptor it will be a stock Bronco belt. Or if they used the brackets off the donor engine, it will be that one.

Yea, we have no idea what belts to tell you to go get. You have unknown non-stock parts from an unknown source. Tape measure, and get an extra belt a size up and a size down. My parent's boat. Took 5 tries to get the right belt. And that was a stock Mercruiser that you should be able to look the part up.

 

[m_m70]

get some rope close to the same size as the belts and wrap it around the pulleys with brackets adjusted closed to the center, mark the rope where the ends meet, measure that with tape and order either from parts store or summit etc........Has worked for me on all my custom pulley setups.

 

[blubuckaroo]

You'd better buy a spare. That setup is going to be tough on that belt.
I'd like to see a photo.

 

[B RON CO]

Hi, my guess is that your engine had a long gone AC compressor, and a thermactor air pump. I would try two belts. One for the crank, water pump and alternator, and the other for the crank, water pump and power steering. Using a skinny tape measure or rope should get you in the ballpark. Make sure the belts are wide enough to ride up on the V and not the bottom of the pulleys. When you find the right belts save the cards with the part numbers. My alternator has a double pulley but I only use the inner. Look at other Ford engines for some ideas. Post a couple of pics if you can. Good luck

 

[RPM289]

Use the rope idea and find a NAPA store they are always willing to help find the right belts.

 

[triracer67]

Thanks for the help. Dudes at parts store were bored when I stopped by the evening took my measurements and found two that will work, I decided to ditch the four pulley belt and go to threes on both. Also, even turning 6,000 rpms I never threw one of the belts, and they are at least 30 years old.

 

[bronconut73]

You revved your eb to 6,000 rpm?

 

[sanndmann3]

Thats where the excitement begins! lol

 

[Broncobowsher]

The belt was probably slipping so much you couldn't throw it.

The last couple of small blocks I built were very happy at 6000 RPM. The 351 with the RV cam even liked it. Only threw one belt. It was just the alternator and happen to be on the dyno. Arizona dry rot probably had a lot to do with it.

 

[bronconut73]

My Windsor falls off a Clif at about 5,200 rpm...
Not complaining ...it was sort of built to make its power and torque down low on the tach...
Sometimes I forget that you fellers build some serious "do it all well" engines. I actually built my engine in '90 so I probably should upgrade some stuff.
I have massaged stock heads. Lots of great parts, Edelbrock, Harland Sharp, Comp, etc....but I think going to a better aftermarket head could open up the top end of my motor before I go after the cam. A lot has changed and some stuff has gotten really inexpensive in the 27 years since I built my 351.
I need to upgrade, lol,

 

[blubuckaroo]

There may be a way to get one "V" belt to engage all four pulleys. But even if one belt could pull the load, I can't see a way it could possibly engage enough of each pulley's circumference to get it to grip.
That's why serpentine belts use a tensioner on the backside of the belt.

 

[5001craig]

I have two V-belts but here's a 6,200 rpm max pull:

[youtube]p6hMXJi6YBQ[/youtube]

WAY beyond the speed rating of these tires...

Keeping my alternator tight helps as well as does keeping the battery fully charged with a Noco .75W tender.

 

[blubuckaroo]

Thanks for the help. Dudes at parts store were bored when I stopped by the evening took my measurements and found two that will work, I decided to ditch the four pulley belt and go to threes on both. Also, even turning 6,000 rpms I never threw one of the belts, and they are at least 30 years old.

I guess this is where this V-belt thread got side-tracked to engine RPM.
I can't see how one has anything to do with the other.
?:?

 

[bronconut73]

I guess this is where this V-belt thread got side-tracked to engine RPM.
I can't see how one has anything to do with the other.
?:?

. [Also, even turning. "6,000 rpms" I never threw one of the. "belts", and they are at least 30 years old.]

Really Blu?

 

[jckkys]

The only V-belt slippage I've seen, is the high amperage alternator. Two groove pulleys on the crank, water pump, and alternator fixed it for me. The rear belt turns the water pump and alternator. The front belt turns those plus the power steering pump. All the pulleys are OE Bronco parts. The power steering pump is tightened last. The length of the belts took some trial and error, to get everything to work. The rope method left me with at least one belt too long. I kept the card board and receipt, so the parts store let me exchange it. You will want to do the same. The part numbers are gone or I would be happy to pass them on. If either belt goes away I can still get home or to a parts store. When I loose a serpentine belt, I'm dead in the water.

 

[Skiddy]

. When I loose a serpentine belt, I'm dead in the water.

that's why I only carry one spare belt instead of two