Jump to content

Chewing Belts


Recommended Posts

Is it common for the crank pulley to come out of line with the rest of the pulleys?

 

My 4l will force the belt off the main pulley within the first revolution every time. And it doesn't take long after that to chew it up (10 mins) so after making sure all my pulleys were smooth and spinning straight, it looks a lot like the main is slowly creeping forwards away from the motor.

Link to comment
Share on other sites

When I was a kid my '34 Chevy did that. I didn't have big bucks for a new one.Didn't have little bucks for a used one. JY kept a mean dog in the yard after hours so I did the only thing I could do. Welded it. Worked fine.

Link to comment
Share on other sites

Yeah, that was me that had the harmonic balancer separating. I replaced it with a new one from NAPA ($52.00) and a new seal ($15.00). The belt is still jumping off the track at the harmonic balancer. The belt starts to wobble past the fan pulley then jumps track on the harmonic balancer. The balancer was separated as I shown in the picture, but there is more going on then just that. The fan pulley doesn't look like it's bent. I took the shroud off the fan to get a good look, but can't see what's causing it to jump track. The belt is also wearing a groove in the timing cover so if yours is off track, better fix it fast or you could end up replacing the timing cover. When the belt is on correctly I can hear a ticking sound from somewhere? The ticking goes away when the belt jumps track. I see some threads that say the radiator has to be removed to replace the balancer, but I was able to do it without removing the radiator. The hard part was putting the new balancer and seal in. The experts say you need a harmonic balancer installer. The price of this was anywhere from $35.00 to over $100.00. I went to the hardware store and bought a 3" and 2 1/2" bolt (1/2"x20). The 3" bolt and a 1 3/'4" socket was used to push the new seal in. The 2 1/2 bolt was used to push the balancer on. The bolt for the balancer is too short to start the balancer onto the crank. You can wedge a screw driver between one of the spokes on the balancer and the timing cover to keep the engine from turning tighten to 80 fp. Switch to the original crank bolt once the balancer is in far enough to thread the bolt in. You should be able to thread it in quite a way by hand so you don't risk stripping the threads. Now, if I can just figure out why the new belt is still jumping off the balancer.

 

pulley2.jpg

 

Mac...

Link to comment
Share on other sites

Harmonic Balancer Installer? I always got a kick out of those. I've always tapped it on with hammer enough to get the bolt to thread 3 or 4 times, then I just tighten the bolt to put it on. It's worked perfectly every time.

Link to comment
Share on other sites

check your water pump. It sounds off topic but the water pump has adjuster bolts and can very easily be very crooked and you not even notice. when i first bought my mj this was an issue. it was out of line and i couldnt even tell, but my dad took one look at it and told me the water pump needed adjusting. it was out of whack just allitle but even so it had let the belt cut a big slit in the lower raidiator hose and ruin that along with the belt. it could be far more out of whack for you guys and could be doing the same thing only more extreme. Its atleast worth checking anyway. i believe its just like a 12 mm bolt you have to adjust, takes all of 6 minutes if your taking your time and is virtually free to fix :thumbsup: maybe thatl do you some good. good luck :wavey:

Link to comment
Share on other sites

lol today i looked again at it and touched the pulley and realized there was rubber between it and thought: well theres my problem.

 

thanks! going to order one asap. hopefully it isn't 50 bucks though..

Link to comment
Share on other sites

i got a new water pump about a year ago but my friend reused my pulley and its got some dings in it so i fixed them all up but should probably adjust it when the rest of the pulleys are accounted for.

Link to comment
Share on other sites

Harmonic Balancer Installer? I always got a kick out of those. I've always tapped it on with hammer enough to get the bolt to thread 3 or 4 times, then I just tighten the bolt to put it on. It's worked perfectly every time.

 

I doubt I could even get a hammer in there let alone swing it. You must have had the radiator out or the engine out.

Link to comment
Share on other sites

Harmonic Balancer Installer? I always got a kick out of those. I've always tapped it on with hammer enough to get the bolt to thread 3 or 4 times, then I just tighten the bolt to put it on. It's worked perfectly every time.

 

I doubt I could even get a hammer in there let alone swing it. You must have had the radiator out or the engine out.

 

I've done it both ways. :dunno:

Link to comment
Share on other sites

check your water pump. It sounds off topic but the water pump has adjuster bolts and can very easily be very crooked and you not even notice. when i first bought my mj this was an issue. it was out of line and i couldnt even tell, but my dad took one look at it and told me the water pump needed adjusting. it was out of whack just allitle but even so it had let the belt cut a big slit in the lower raidiator hose and ruin that along with the belt. it could be far more out of whack for you guys and could be doing the same thing only more extreme. Its atleast worth checking anyway. i believe its just like a 12 mm bolt you have to adjust, takes all of 6 minutes if your taking your time and is virtually free to fix :thumbsup: maybe thatl do you some good. good luck :wavey:

 

I don't see any way to adjust the water pump pulley. It just bolts against the flange on the end of the water pump. Could you tell me where this adjustment is?

Link to comment
Share on other sites

I would like to see more about this water pump adjustment bolt, Pics? A more detailed description of exactly where it's located.There 4 or 5 bolts,I forgot how many exactly, holds the WP to the block. There are 4 bolts. or studs holding the fan to the pulley. But no adjustment bolt.

Link to comment
Share on other sites

I would like to see more about this water pump adjustment bolt, Pics? A more detailed description of exactly where it's located.There 4 or 5 bolts,I forgot how many exactly, holds the WP to the block. There are 4 bolts. or studs holding the fan to the pulley. But no adjustment bolt.

 

There is no in or out adjustment on any pulleys. The only adjustment is on the power steering pump and that is to adjust the belt tension.

 

pulley3.JPG

 

Mine continues to jump track. The water pump seems good, there is no in or out movement or looseness. It spins true with no wobble. Same with the fan pulley. I am now suspecting the water pump pulley itself may be bent out of round on the back side.

Link to comment
Share on other sites

it doesnt actually have a bolt just for adjustment, but it can stil be off kilter.

 

 

I suppose whoever replaced the water pump could have left some old gasket material causing the pump to be off kilter. When I look at the back of the water pump pulley it has been contacting the water pump housing on 2 sides. To me this would mean the pulley is somewhat oval or cupped a little or the water pump bearing is truly bad even though it seems fine. Also, if the bearing was bad the pulley would have made contact all the way around and not just 2 sides. Unfortunately, I haven't been able to locate a new or used pulley yet. When I do I'll trace them on paper to see if the old one has warped. To the naked eye the pulley looks okay, but to the naked eye from 50 feet I have a rust free Comanche.

 

Mac...

Link to comment
Share on other sites

  • 9 months later...

anyways, a long long time ago i fixed this with the new harmonic balancer. used a puller kit and had enough room without moving the radiator! it took 30 minutes.

 

but you guys are right, there isn't any adjustment to the water pump pulley other than maybe some shims or washers but none was necessary. i de-burred the flanges and I haven't had a problem since!

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...