Had an interesting experience with fan belt for my 31. The belt sold by Filling Station and recomended by Bill Barker is a 5L390 (the 390 means 39"). When I put that belt on my car it was way too long. The generator was tilted way over and not in correct postion. After some research and a lot of emails with Chevy "experts" and car owners here is what I found out. Whether it is correct or not I will leave up to you but it works for me. JunkYardDog says (and if he says something it has to be true) that the correct belt is a DAYCO 24380 (380 means 38"). I have spoken to 3-4 other guys and they all agree. Some cross over numbers are Gates TR22373,Goodyear 24377, and NAPA 2524379. You can order the DAYCO 24380 on-line at http://www.advanceautoparts.com for $14.99.

You might want to inform FS of your research, I think they would like to know this.

Another 2 cents worth from a former auto parts dealer. Any belt which starts with 3L, 4L, 5L, etc is referred to by it's manufacturer as a "fractional horsepower" belt. The number preceding the L indicates the width (perhaps in 1/8 inch increments, 5 meaning 5/8 inch) You will find belts with these numbers hanging on the wall in hardware stores...think about it. These belts are not intended for automotive use, and if my memory is correct, have a different angle to the V than an automotive belt. I have used them in a pinch, and would again, but they are not the correct belt for any car.

The Filling Station already knows from what John tells me.

Hi guys,

Have informed Filling Station of what I found out about 31 fan belt. Also sent email to DAYCO and they were very nice in giving me a list of suppliers in my area. Also been advised that "fraction horsepower " belts should not be used on cars. The belt I orderd from advanceautoparts is aready on its way and should be here on monday

Thanks for the update, JunkYardDog. I know the FS has devoted Chevy people owning it who care and are helpful members of the VCCA.

Hi All,

Steve from The Filling Station here. Just thought I should respond to this thread. First of all, we used to carry the Dayco 24380 belt for this application. We still would except that, Dayco, as with most other manufacturers, has changed all of their belts to the "cog" type. These have notches at the inside edge as do all modern belts. This is not correct for a restoration. If anyone has a Dayco 24380 without cogs, I would be willing to look at having them made. We checked with Dayco about having the belt made without cogs, but they wanted a huge amount of money to do them.
Yes, the belt we now carry is a "fractional horsepower" belt. The 1929-32 engines, at most, put out 60 horsepower. I have personally run this "fractional horsepower" belt on two of my old Chevys - a 1932 pickup and a 1931 coupe. Both of these vehicles have been driven hard and long (over 15,000 miles each)with no belt failure.
We are willing to listen to alternatives, but from our research, there aren't any - except what we have now - or making a new reproduction. I invite your input to help solve this problem.

HI,

I have both the Dayco 24380 and the NAPA 2524379. They are the same size. Both are cog belts. The only difference is the NAPA belt has a smooth outside surface where the DAYCO has an ouside surface that looks like a flat version of the inside cog.
Mine is not a show car so I personally do not need it to be an exact reproduction. However I can totally understand that if you have a show car you would want something that more closely looks like the orginal. However if you do not have a show car then the these other belts offer an option.

I went out to the garage and checked both of my older fan boxes... they were both 5L390... Napa and an "off brand" which means 39" length. Then I looked at the belt as installed on my 31 Sport Couple. It did appear to be too long, but it did fit... the generator bracket had about 1/4 " of space left on it for adjustment. A shorter belt (38") would have worked better.

It's been about 5 years since I purchased these and I now remember getting caught up in the "cog" verses "smooth" issue. Now that I've read Steve's note, I will go out tomorrow night and check my other cars and see if I have an original (eg. older) belt that Steve could use for reproduction. I'd be more than happy to let my car sit this winter so that the hobby gets a new supply of these parts!! Thanks Steve for your continued support. We need to help you help us!

Steve found an original belt in very nice condition and he is currently working on having the correct fan belt reproduced. The new belts will be 38" long, which is the correct length.

And what color was this original belt???red or black???

Black.

I have a few new GM 836347 belts-look like they could be from the 1940's,Number is moulded on.Sure the originals were different as they had the bow tie and no part number.

This is very cool, Chevy guys who care helping each other with a problem with a good result; doesn't get much better than this...together maybe we can do the impossible?

I talked with Dayco last year about doing a run of the original non cog belts and then I had talked with Larry Jackson who has work experience and Steve of the filling station about having a run of the 24380 dayco belts run but with no results. Dayco at the time would do the run but wanted to go through one of their distributors which would give an extra mark up that could make it cost prohibitive. I know that Larry was busy also with the gear runs. If this has changed maybe Steve could let me know.

Talked to Steve about it two days ago and nothing has changed. Dayco still insists on going through a distributor.

Any way Steve can become a distributor for Dayco? or a limited distributor? Does Steve know a distributor that maybe would work with him on this project?

Just brainstorming here...trying to find a way to solve the problem...

Anyone else out there who could make the belt?

FYI Gator, I have run a Fractional HP belt on my chevy six and haven't had a failure, yet! I do carry a spare. I only pull the WP, fan and generator and don't tighten them any tighter than the book (Chevy manual)shows. I had not noticed the difference in the "V" difference till I saw it here. In fact,I also didn't know it was a fractional HP belt, until I saw the "L" in the number because I got it at a national parts house!

Well, anyway since it ain't broke, I don't intend to change it now!

Steve has to buy the product from one of Dayco's distributors......that's how it works.

...And that is the American way, You gotta go thru normal channels or if you can't find it at NAPA, Auto Zone, Wally World or Harbour Fright maybe They will have it at The Fillin Station or Chevy's of the Fortys........

Except that if the Filling Station pays Dayco to make the fan belts, the Filling Station still has to go through a distributor to purchase the belts that the Filling Station had made.

I'm doing a frame up restoration on my '31 and I want everything to be as correct as possible. I found this old thread last week, and based on its information, I purchased the belt the Filling Station lists as a '29-'36 passenger fan belt. It arrived yesterday. It's a Gates 5L390, and the label says it's for 3 to 17 HP use. It may work fine, but I must be doing something wrong. The upper generator bracket I recently purchased is 7" long, and does not have a curve at the generator end. Is that correct? I attached one end of it to the bottom bolt on the water pump and the other to the top ear on the generator. Is that correct? If the bracket is correct, and I have attached it correctly, the belt is way too long. Any assistance would be appreciated.

The generator brace is 7" long and it has a slight curve to it. The brace attaches to the upper bolt on the driver's side of the timing gear cover, not the water pump, so you have the installation of the brace incorrect.

Also, is the belt that you purchased from the Filling Station a solid belt or a cogged belt? If it is a cogged belt then that too is incorrect.

6wheel, I have purchased several good NOS original belts from ebay.

Post a message on 'parts wanted' section here on Chatter for a belt and you might get lucky also.

Good Luck.

Thanks Junkyard Dog, I found the bracket that you described in one of the many boxes of parts that came with my car (basket case) and installed it as you advised. It seems to work fine, but I won't know for sure 'til I find the right belt. I'm now looking locally today for a 5L360 belt, which I think will be the right length, and will work 'til I get an NOS one. I'm still months away from driving the car, but maybe I can drive the chasis around the block soon. Thanks also to Louis C.- I'll watch ebay and post an add in parts wanted.

Cool! Glad that you found the correct brace for your generator. On the new old stock belt.....be careful with those because I have had several and, due to their age, they were brittle and hard as a brick and not really that serviceable.

i buy mine at the local tractor supply they are not cogged and made of kevilar probably may have to never replace . hope this helps

The kevlar belts from Tractor Supply are green color but can be lightly painted with flat black paint to make them look more original. I have run several fractional horsepower belts from the local hardware $ 4-7 and the kevlar belts without any problems. Eventually any belt will fail because of heat, light and atmospheric gas which causes them to harden.

Well, I spoke too soon. The 5L360 belt is too short, and the 5L370 is too long, and they don't come in half sizes. Maybe a kevilar belt is the answer. I'll be near a tractor supply house in the morning. Could it be that the bracket I found is too short? It is a total of 7" long, and slightly curved at the generator end. I mounted it as Junkyard Dog advised.

It sounds like you have the correct generator brace. The problem is that you probably don't have the correct length fan belt. The length of the belt should be approx. 38 1/2". See if you can find a Dayco 24380 fan belt. Those work great and they are the correct length as well.

Unfortunately I don't remember the number of the TSC belt but it is the wide 38" one that fits. The 36" belts fit the late four bangers.

Interesting belt...

ebay belt for sale

I don't know but I don't think it is original....maybe a later replacement belt? The experts will know.

Just checked the belt on one of my '31 engines. it is a 5L380 fractional hp belt. The length is just right putting the adjustment about 3/4 of way to the end of the slot in the brace.

Thanks for the help guys. I bought a 5L380 fractional hp belt yesterday (nice green color!), and it comes closer than anything so far, but still doesn't fit. When I put it on, I'm unable to tighten it. The adjustment brace is at the end of its run, and it needs another inch or so to tighten. As I said previously, the brace is 7" long and has a slight curve at the generator end. If it were one or two inches longer, it would work great. I mounted it as Junkyard Dog advised. It's kinda weird 'cause earlier I bought a 5L370 belt, and it was too long - it must have been labeled wrong. Could I have a larger pulley on the generator (3 1/4") or water pump (4 1/8") that would cause this? I'm considering asking a machinist friend to make me a slightly longer brace to solve the problem.

I don't understand why you are having a problem. Just measured two '31 engines with 7" long braces. The generator pulleys are ~ 3 5/16" diameter and the water pump pulleys ~4 1/8" dia. One has a 5L380 belt with generator bolt ~ 1" from the end of the slot. The other uses a Gates Powerated 6938 belt with a similar space on the brace. Do you have the correct generator? It should be a Delco-Remy Model 943J.

6wheel, have you measured the belts you have?

I don't know why you can't get the fan belt to fit either. The correct belt measures 38 1/2" and if your belt measures the same then it is correct.

A 39" belt on my '31 Sedan is barely tight enough not to slip with the adjustment out to the max. I could see it vibrating and it made a buzzing sound at driving speeds. I now have put on a NOS belt that is a perfect fit. It is a John Bull #55, made in England. It's NOS from the 50s or 60s so it may turn out to have a short life. Does anyone know what a John Bull #55 was made to fit?

I have a 38" to 38 1/2" (depending upon how you measure it) belt on my car and it fits like a dream! With this belt the adjustment bolt is right in the middle of the long slot at the end of the generator brace...just as it should be. d2d2....it sounds like your 39" belt is too long, and that is probably why you are at the end of the adjustment.

I have three different new old replacement stock belts, and they all measure 38" to 38 1/2" long as well.

By the way, the John Bull #55 belt is not a NOS belt. It is a "new old replacement stock" (NORS) belt and it is an aftermarket item. A new old stock belt would be an "OEM" item (original equipment manufacturer) which is new original belt from Chevrolet with the correct Chevrolet part number and etc.

I don't care if it's NOS, NORS, or whatever. John Bull #55 looks right and works right so maybe I can get some others if I find out what they fit.

Just trying to keep the terminology straight for the new dudes that don't know the difference between NOS and NORS since the terms are not the same.

Yep, any aftermarket belt will work great if it is the right length. Sounds like the John Bull #55 will work fine if you can locate more of them and find out what the application is.

:p

Thanks Chipper, I think you are on to something. The generator is a Delco-Remy. Tags from both generator and starter were removed by the rebuilder, but I saved them. One says 943R 227371, and I assume it is from the generator. The other tag says 714L 860809. What year is the 943R? Is it larger or are the ears located differently than on the 943J?

If I remember correctly the 943R is a '30-31 Chrysler generator. Also fits DeSoto, Dodge and Plymouth maybe others. I think I have one around here somewhere. Maybe the dogface can tell if the housing is different than the Chevy.

The housing is the same, and if you are using the correct dia. generator pulley on your 943-R generator then the 38" to 38 1/2" fan belt should fit just fine.

Do you have the correct harmonic balancer on your car or the correct engine?

Junkyard Dog, the # 2879918 is stamped on my engine behind the fuel pump. Casting # is 8364 9 and date code is H 10 1. So, it is a '31 engine, correct? The harmonic balancer is 5 7/8" in diameter.

Yep, you have a 1931 engine.

Louis C., I measured the new green belt, and it's 38 1/4" outside. It comes closer to fitting than any of the others, but I still need another inch or so of adjustment on the upper bracket to snug it. Dog, are the mounting ears in the same locations on my 943R generator as on the 943J?

I just checked my Delco-Remy parts book and while the generator housings and the comm. end frames are the same for the 943-J and the 943-R generators, the drive end frames are different. That is probably your problem.

You might want to check into getting the correct generator for your car.

Guess I need to find the 943R that I have stuffed somewhere and check it versus the 943J. I will look later this evening.

One of the '31 engines actually has a 943R generator on it. With the 7" brace mounted in the top large bolt in the timing cover and 5L380 belt the adjustment bolt is about 1" from the end of the slot. Now I assume that all the parts in the 943R are correct including the front plate. The front plate appears to be the same as the 943J generators so it might have been changed. If that is the case then it might still be the problem.

Thanks guys, Sounds like I might be able to just replace the front plate on my generator. I'll be going to a huge swapmeet and car show at Petit Jean Mountain, Arkansas in 2 weeks. Maybe I'll get lucky and find a 943J among parts brought in by over 1200 vendors. This will be the 32nd year I've attended this event. It's one of the few places in this part of the country where more than a handfull of pre-war cars and parts can be found.

Here's the longer belt... you can see how close it gets to the end of the arm.

Thanks Bill, I see the difference now between the front plate on your 943J and my 943R; the top ear is pointed in the opposite direction on mine, which limits the amount of adjustment I have.

As the Delco-Remy parts book indicated, the drive end frame on the 943-J is different than the drive end frame on the 943-R, so now we know what the difference is. Looks like you need to find a 943-J generator (which is the stock generator for your car) and then your problem with the fan belt will be solved.

nice job solving this mystery, guys...ain't the vcca great?..


epi

The VCCA is great! Thanks guys. I finally found a used generator with the corrrect front plate and mounted that plate on my rebuilt 943R. It works! My fan belt is now in the middle of the adjustment range.

I still need some help to finalize this part of the project. I bought some reproduction number plates for my generator and starter from the Filling Station, but haven't been able to find a number stamping set with small enough digits to replicate the originals. Does anyone have a source for them or know of someone who can stamp them. The beautifully rebuilt distributor that came with my basket case car has a reproduction tag on it with the correct size digits. Who out there rebuilds distributors?

Take your plates to a trophy shop and have them engrave the numbers to match your old ones. It will look great.

On the correct belt Bruce DeFord emiled me last month and said," I just found out that a Triumph uses the same belt and I called a place here and they get them for England, no cogs." He didn't give me specifics and was going to GJ at the time. Maybe Bruce can fill us in on this.

Hey Guys,

I had forgotten about doing this, I'll see what I can come up with. Thanks Doug.