“Correct” fan belt doesn’t fit

Re: “Correct” fan belt doesn’t fit

As 35fordtn stated,you need to source one.You might start by taking a circumference measurements (with gen at bottom of intake and at the top) at the pulleys edge . From that you can find the belt that will work.

Here is a chart that might help.Disregard what I circled in blue,that was for my application,36 engine in a '33.Took me 3 attempts to get it right because I used an alternator conversion.
 

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Re: “Correct” fan belt doesn’t fit

As 35fordtn stated,you need to source one.You might start by taking a circumference measurement at the pulleys edge . From that you can find the belt that will work.

Here is a chart that might help.Disregard what I circled in blue,that was for my application,36 engine in a '33.
574508
 
Re: “Correct” fan belt doesn’t fit

The table above shows a good bit of info. That for a B series belt, the belt number is 3 less than the circumference. So measure the circumference around the outside of the pulleys and subtract 3. That will give you a belt size. B denoted the profile. A Ford will take a B type belt.
You can get B series belts from Industrial bearing supply places and ebay. You don't need an automotive supplier.
Mart.
 
Re: “Correct” fan belt doesn’t fit

With the generator up higher, will the fan clear the radiator? I’m not fully familiar with 37’s.
 
Re: “Correct” fan belt doesn’t fit

With your engine exposed like this you can pretty easily figure out the belt length that you need.

- Make a mark on your crank pulley and the belt in the straight down position
- Hold the belt in place there
- Pull the belt over the generator pulley, straight up position and make another mark
- Take the belt off, measure between your marks and double the value
- Look for the next longer belt but shoot for around maybe 1" or 1-1/2" longer
 
Re: “Correct” fan belt doesn’t fit

With your engine exposed like this you can pretty easily figure out the belt length that you need.

- Make a mark on your crank pulley and the belt in the straight down position
- Hold the belt in place there
- Pull the belt over the generator pulley, straight up position and make another mark
- Take the belt off, measure between your marks and double the value
- Look for the next longer belt but shoot for around maybe 1" or 1-1/2" longer
AND paint it back Ford Green IF you so desire
 
Re: “Correct” fan belt doesn’t fit

With your engine exposed like this you can pretty easily figure out the belt length that you need.

- Make a mark on your crank pulley and the belt in the straight down position
- Hold the belt in place there
- Pull the belt over the generator pulley, straight up position and make another mark
- Take the belt off, measure between your marks and double the value
- Look for the next longer belt but shoot for around maybe 1" or 1-1/2" longer

This is a good recommendation. Get the dimension described. Double it. Add an inch. Then deduct 3 and order a B series belt that length.

Example: Described dimension (belt wrapped around one side, from bottom of crank pulley to top of generator pulley) lets say it's 28".

Double it. 56" add one. 57".

Deduct 3 to get belt number (based on info in table) Belt required is a B54. Should be easily available.

Trial and error might then dictate whether it is right. You might need a B53 or B55. Half inch sizes are also available but can be more expensive and harder to find.

I used to get belts locally but have to order them off ebay now. Very easy to get what you need.

Mart.
 
Re: “Correct” fan belt doesn’t fit

AND paint it back Ford Green IF you so desire
Nah, it was blue when I took it out. Expected green but cleaning off 60-70 years hid the blue. Probably due to it being an OEM dealer replacement engine.
 

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Re: “Correct” fan belt doesn’t fit

Be careful when tightening your generator up to adjust belt tension. The first picture shows the generator not lined up with the slot in the intake. You can easily break the edges off the slot on the front of the intake if the generator is not lined up. Both cast aluminum and cast iron intakes will break, the aluminum ones are slightly more prone to breaking.
 
Re: “Correct” fan belt doesn’t fit

Between 1933 and 1953 flathead V-8’s (of the 85-100 hp variety) there were a total of three “long” belts used by Ford. We stock all three types of. When the customer calls for a belt, I always ask them “is your engine application stock or modified?”

Most times they’ll reply that it’s stock. I match that up to the correct belt and ship it out. Half the time they call later after receiving the belt and state that it doesn’t fit. All we can do is to take it back and issue credit.

Other times they’ll respond that the application is not stock….they’re running an aftermarket alternator. Due to the smaller pulley on these, none of the standard Ford belts are going to fit properly. We back off suggesting one of our belts.

This thread is further proof that other modifications (often unknown to the customer) will confound the buyer when trying to replace a belt. The suggestions for sizing a belt application are good advice.

And this is why I don’t love selling belts…….
 
Re: “Correct” fan belt doesn’t fit

Just a thought but if a few people would measure the overall diameter of their pulleys and the center to center distances of the two and what belt they are using we might have a good starting place.
Wayno
 
Re: “Correct” fan belt doesn’t fit

The earlier pumps in the heads belt fits nicely. Now I just need to find someone in Phoenix that needs a new ‘37+ one to donate to.
 
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