“Correct” fan belt doesn’t fit
 

The listed 78-8620-B fan belt doesn’t even come close to fitting over the second water pump on my ‘37 21 stud engine. Generator is fully down. Water pumps are listed as correct for a ‘37, though you never quite know with Chinese parts.

Am I missing something?

Re: “Correct” fan belt doesn’t fit
 

Re: “Correct” fan belt doesn’t fit
 

I think this a known bad part number. I believe there are several posts on the "Early V8 General Forum" addressing this. If no answers appear, a search of the forum should yield the information you need.

Re: “Correct” fan belt doesn’t fit
 

Did you buy them from Bob Drake? They looked pretty and came in nice packaging, but neither belt on my ‘46 Mercury would fit. I figured that I’d break a chunk out of a pulley if I tried some force, so I threw the belts on a shelf and bought belts from Dennis Carpenter. They fit fine. Very frustrating when the simple stuff isn’t right and they have a very short duration for their return policy.

Re: “Correct” fan belt doesn’t fit
 

Could it be it's made to fit a 21 stud with the water pumps up on the heads and not the late '37 21 studs with the water pumps on the block.

Re: “Correct” fan belt doesn’t fit
 

Could it be it's made to fit a 21 stud with the water pumps up on the heads and not the late '37 21 studs with the water pumps on the block.


not with a 78 prefix!

Re: “Correct” fan belt doesn’t fit
 

I think they use the same belt.
Brian I will be over in NZ in a couple of weeks, with the gauges and stuff.
Lawrie

Re: “Correct” fan belt doesn’t fit
 

IS it me or does it look like he has an early intake manifold and the generator is up higher than where the 37 "normally" would be??? It SURE looks like it.........Especially IF the avatar picture is the actual car...1935...maybe they used the 35 intake on the 37 block??? Looks like the distributor and coil were swapped too.


Maybe post a picture of the intake and especially the front part of it

Re: “Correct” fan belt doesn’t fit
 

Lets see the intake manifold and the generator. Generator does not appear to be down maybe due to incorrect intake.

Re: “Correct” fan belt doesn’t fit
 

My bet is on this Terry.

Re: “Correct” fan belt doesn’t fit
 

Re: “Correct” fan belt doesn’t fit
 

That’s likely it. The ‘37 was a factory exchange block back in the day when the dealers did that.

Re: “Correct” fan belt doesn’t fit
 

Yes

https://www.fordbarn.com/forum/attac...2&d=1759153599

Re: “Correct” fan belt doesn’t fit
 

Found this table of NAPA belts on the HAMB

https://www.fordbarn.com/forum/attac...7&d=1759155027

Re: “Correct” fan belt doesn’t fit
 

The intake you have is a correct 1935 intake.....SO you will more than likely need the correct belt for 1935.....I am not sure IF the water pumps being in the block and the water pumps being in the head will make "that" much difference BUT it will be a darn bit closer than what you have....as the 1937 intake mounts your generator lower on the front of the engine, hence why it is too short now. OR you can swap intakes and get a 1937 intake, then your belt will work.

Re: “Correct” fan belt doesn’t fit
 

azlkk


IF you didn't see in my post above, your distributor and coil are ALSO 1935 correct so keep that in the back of your mind as well!!! NOT 1937

Re: “Correct” fan belt doesn’t fit
 

Unless you find a 1937 intake you will need to source a belt on your own. As stated that is a 35 intake but a 35 belt won't work, as 35's had the pumps in the heads.

Re: “Correct” fan belt doesn’t fit
 

Just posted on YouTube one-hour ago, late 21 stud motor and the guy is complaining about how everything is different.

Normally I keep a bunch of different "cut" width and length belts in the shop. I never throw old belts away I put the generator/alternator on at its lowest point and wrap the "correct" width belt and cut belt around the pulleys and make a measurement of the belt, then I go and get one that length. Make sure the belt you choose is the correct width, that the belt rides on the beveled sides of the pulley and not the bottom of the pulley's grooves. The parts stores usually have the belts arranged by the width size and length so it's easy to find the one you're looking for, and they will exchange it if you need one a little shorter or longer. I have Gates and Dayco catalogs that list the belts in order of their lengths which helps. I kept all the old parts catalogs from work; they come in handy.

Looks like the same engine we have been talking about.

https://www.youtube.com/watch?v=zNx1dxmuNVg

Re: “Correct” fan belt doesn’t fit
 

It is the same engine, Ed Smith rebuilt it for me.

Re: “Correct” fan belt doesn’t fit
 

Did K R Wilson make a fan belt stretcher?

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.

Re: “Correct” fan belt doesn’t fit
 

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
 

AND paint it back Ford Green IF you so desire

Re: “Correct” fan belt doesn’t fit
 

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
 

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.

Re: “Correct” fan belt doesn’t fit
 

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.