The Stovebolt Site Forums The Shop Area Engine Shop Burning Fan Belt- '52 3100

Guys, I'm going through fan belts way too often in my '52 3100 with a 235. . I've noticed every time I go around a sharp right curve I smell rubber burning.(No I'm not going around on two tires so it's not that.) Before long, my fan belt starts squealing a little, then a little more in a few days then...snap. Could something be shifting causing additional stress on the belt- loose motor mount or something? The pulleys all match in width, are lined up correctly and the belts fit perfectly. Any ideas?

1st swag would be busted motor mounts. Shake the engine back and forth to see if theres any play.

I'll give that a try and report back. Thx for the input.

Chock the rear wheels front and back, then try to drive forward and reverse. Have someone check for engine movement that might put some kind of stress on the belt.
Jerry

Would not have thought of that. I'll try that too. Thx Jerry.

....and last but not least, after HRL's suggestion, Check the water pump when you have the belt off. Sounds to me like you may have a water pump trying to lock up??????

Sometime ago had one that squealed on occasions and being young and dumb I just figured it was due to the fast RPM changes I was always putting it through...but yep, water pump. I figured it out when the belt did nothing but slip and smoke with the pump locked up!

I am having trouble understanding how a broken motor mount would effect a fan belt. You can hang a running engine from a tree and swing it to and fro without affecting the relationship between the fan/crankshaft/generator pulleys.
You likely have a bad water pump. Look for water showing at the weep hole on the back of the water pump. When the bearings go bad, the seal begins to fail (and vise versa). When the bearing begins to fail, the pulley will deflect causing extreme belt wear.
It could also be caused by a misalignment of the alternator/generator, or bad bearings inside the alternator/generator.
Carl

Just to be clear guys.... I can put a new belt on and drive for days with no squeaking at all and no burning rubber smell. However, the first time I drive around a sharp right curve I smell rubber burning. After a couple of sharp right curves the belt begins to glaze and squeak. Once this happens, it doesn't last much longer. The burning rubber smell and belt wear NEVER happens during straight driving or around sharp left curves. I'm going to try the suggestions above today and will report back. Thx for the water pump suggestion Alvin and Carl, but I already changed it. Of course, that doesn't mean I got a good one when I did! There is no water leaking from the weep hole though.

look at the full path of the belt, around each pulley, etc. Also, when it first starts to smoke and glaze, where is the glazing? on the inside, or one edge on the outside? I would suspect that on a sharp right, something is shifting and getting too close and hitting the belt.

Also, I don't see this called out but, I am assuming this is not going around a power steering pump, correct?

Mike. You are correct there is no pwr steering pump/pulley. There is nothing anywhere near the pulleys to come in contact with the belt. The glazing is occurring on the tapered sides where the belt contacts the pulley. The top of the belt and bottom of the belt are fine.

sitting still, with wheels cranked sharp to the right, does it squeal?

What gen. or alt. do you have. There is not a lot of contact area on the 6 cyl. engine for the gen. If it is a high amp gen. or alt. it will put a lot of stain on the belt & it will slip. Check the charging voltage. It should not be over 7.5 on a 6 volt or 14.5 on a 12 volt. There are some cheapy fan belts out there also. Be sure & use a major brand.

The fan belt rides on the water pump, on the harmonic balancer, and on the generator?

They are all attached to the block (and move with the block).

I'd guess a bad bearing in the water pump or in the generator (and, more unlikely, a loose/wobbly harmonic balancer).

Also, you might as well check the sizes of the grooves in all pulleys - are they the same - what width fan belt do you have?

Maybe a link to some pictures for a better idea of what may be happening.

Double check the harmonic balancer.... does it have a bolt in the end of the crankshaft holding it on?
With the belt glazing on the tapered side it sounds like something is out of alignment. That leads me to believe the crankshaft pulley is the culprit since you have a new pump and are the generator pulley doesn't sound like its moving back and forth....
lastly, is he pulley on the generator tight? (if the fan pulley was loose it'd do it all the time)

Go race in Nascar, they only turn left.

I would suspect a bearing failing in either the water pump or generator. Take the belt off and turn the water pump and generator by hand to see if either one is hard to turn or is wobbly.

One other thing to think about, and this might be far fetched, but could the wiring to the generator be mixed up causing it to put extra stress on the belt while running? Seems to me if I remember right you can make a generator run if the wiring is correct to it. Could it be trying to do that and fighting against the belt?

I can't see any way turning right or left would have any effect on the belt and generator.

Perhaps the regulator is not shutting the generator down when the battery is charged.

I've been out of the loop for a while and haven't been able to get back with an update. I tried having the truck idle while I jacked it up from the passenger side causing it to lean toward the driver side. I thought I might be able to duplicate the problem. No deal.

All of the pulley's are the same width, are lined up properly and are not wobbly. The Gates green stripe belt I'm using is just under 5/8" wide. The alternator is a 14.5 volt one wire.

I know it makes no sense at all, but I'm going to change the motor mounts to see if it helps. I'm not sure what else to do at this point.

Any ideas would be welcomed!

Unless one of the pulleys is hitting something while turning (highly unlikely) then new motor mounts won't fix it. The front motor mount is it under the balancer (crank pulley)?

If not I can;t see any way the belt or a pulley could bind on something during a turn.

Have you tried to turn the generator and water pump by hand with the belt off to see if they turn smoothly and easily?

I think you have a bearing going out in either the water pump or the generator.

But will be glad when you find the answer.

I had this issue with a 1 wire alt. It was of course a 100 amp beast and took 2 belts to solve the issue. Not my favorite way to solve things. The real issue was and still is a funky mount set up. Still unable to get the owner to consider changes(it is chrome and shiny and has aluminum heads....on and on). Under tension on the belt, big mechanical load(big output) and smoking belts. Only good thing about the set up, it charges the start load fast. After that it quits loading the belt so much.

Is there a polished area on the oil shield which covers the front motor mount where the belt or pulley is making contact with it??

Roy, the front motor mount is under the harmonic balancer. Both the water pump and alternator pulleys turn freely without wobble. I could understand how a bad bearing could cause the problem, but that doesn't answer why it only happens when going around a right curve. I can drive all day with no problems and the first sharp right curve I go around will cause result in the belt burning so much I can smell it while driving. After a few of these curves- snap!

Steve, what do you mean by funky mount setup? Are the pulleys not lined up?

Seems to me if something were rubbing as you were making the turn you would hear it since it burns the belt so quickly.

I will be as glad as you are when you finally figure it out. Wish I were closer. Would love to take a look at it with you.

Please let us know what you find cause I would like to know.

Turning hard right would make the engine list to the left (drivers side). Is the driver side engine mount close enough to the alternator it could catch the fan of the alternator on a hard turn? But I would think you would hear that happen, it would be pretty loud.

Be pretty obvious too because the fan and what ever it hit would be chewed up shortly.

Hmmmm....

Does anyone know if there is a solution to this issue? I have the same problem only when I turn left.

1049 3100 with a 1956 235 CI w/ alternator

Hope to get some advice - THX for your help

People have discussed heavy amp loads binding up the generator/alternator.

Is there anything electrical that may be trying to short or create extra load on the system only during right hand (or left hand in ia49's case) turns? Maybe a wire under-hood or under-dash that has enough slack to move and touch something it shouldn't, or something to do with the horn or turn signals in/around the column when the wheel is turned a few turns that way? Is the battery secure? Is the ammeter indicating anything odd during turns?

Mount a Go Pro camera under the hood pointing at the fan belt and take a test drive. The other option is to recruit a friend with the C.O. Jones to ride a fender with the hood partially raised, and watch what's going on.
Jerry

Did you check your rear mounts- if one is toast/loose/broken, it might cause the engine to lean during cornering. When I bought my '50 3600, the harmonic balancer was barely rubbing against the front mount cover. After pulling the engine I found a squishy front rubber block in there... sounds to me like one of your mounts is either loose or worn out. It is possible that even your rear crossmember could be cracked/loose.

Also, I'd like to be there to see someone try to "shake" a 700 lb engine to see if the mounts are bad....

I think the only way to check it out would be to try to gently jack each one of the rear mounts to see if the trans lifts at all... Good luck!

You can also put the parking brake on, put it in gear and gently let out the clutch while someone watches the engine to see if it moves/rolls left/right at all.

I am trying to understand how a loose motor mount/rocking engine will change the orientation between the fan belt and pulleys, causing the belt to burn.

ditto on Carl's comment

Also, I have IDed loose motor mounts by rocking 235/261 engines "in place". (this was embarrassing because they were new and I had installed them)

Since this is a rather bizarre occurrence, I'm just trying to think outside the box...perhaps I was in the wrong box to begin with, though. But I have witnessed the crank pulley riding on the front motor mount with these engines.

How about: Gyroscopic precession acting upon the rotating fan when making a hard right turn, combined with a worn water pump bearing causing it to bind? Or perhaps acting upon the rotating assembly in the alternator causing it to bind?

Perhaps the fan belt is the wrong width and it is riding too deep or too shallow?

So far, every suggestion in this thread has been either a WAG or a SWAG. The veterans on the forum will understand those terms immediately- - - -others might need a translator. The fairly recent invention of small, durable, and inexpensive cameras has opened up all sorts of ways to see what's going on in formerly inaccessible places like under the hood during a test drive. Hence, my suggestion of a GoPro, even if an underhood light might also need to be used. It beats all the guesswork!
Jerry

Far be it from me to ridicule an outside-of-the-box thinker, as I consider myself one from time to time.
I have at times, been a fair hand at spreading manure when pushed into a corner. But taking into consideration your most recent post, it appears not only have I met my match, I find myself way out of my league in your presence. Well done!

I think Carl has summed this up nicely.

However, both of your out-of-the-box suppositions are easily tested:
- turn off the engine
- take off the fan belt
- spin the fan and look/listen
- spin the generator pulley and loo/listen

Nonetheless, I learned something from your post:

Gyroscopic precession is a phenomenon occurring in rotating bodies in which an applied force is manifested 90 degrees later in the direction of rotation from where the force was applied.

???

I don't see a response by the original poster....so I sent him a PM to see what has been going on.


....and the lucky winner of this contest is____________?
Gosh, Carl is rubbing off on us!

lol... thanks (I think)

I have to say though, that this right turn causing a fan belt to burn has had me thinking abut it all the way to work and back today...very strange.

Does the OP have power steering installed? I've never seen it, but would it be possible for the steering system to be under some kind of severe load while turning in one direction, but not the other? I'm out of ideas.

OK, Good thing we have a retired Professor in our midst, that can explain to us gear heads what Gyroscopic precession means. I was not going to look that up.

Gyroscopic Precision: means the ability to go around in circles where the radius is constant and the arc of the path does not deviate. Jeffrey

Thanks, Tim and 32vid. I now know what ya'll were talking about.