Morbark Chipper belt squealing at high rpm

[ToxicTrav117]

I have a 2002 Morbark chipper that has a belt squealing problem. The maximum rpm of my chipper's engine is 2,200 rpm. When I put a medium-sized piece of wood through it the drive belt squeals like a bastard when the RPM's drop to around 2,000-2080 RPM. I have the auto-feed system setup to reverse at 1800 RPM so the chipper just keeps feeding the wood through even though the belt is squealing. I originally thought my auto-feed system wasn't working because obviously, I thought it was stalling the chipper but apparently it's just the belt because the RPMs of the engine barely drop at all. I took off the belt cover and the belts look brand new although as far as I can remember they are the original belts with about 3,000 hours on them. The belts seemed pretty tight but I am completely lost as to what is causing this issue. Any ideas?

 

[cookies]

over time the rubber dries out,it has petroleum based oils in it and they evaporate out with sunlight and heat over time causing the rubber to get harder causing slips then the rubber gets working "glazed" becoming even harder(usually in a section of the belt) , it will then get too hot as it slips more resulting in melting. over time it will melt enough to get on the pulleys requiring them to be scrubbed clean when the belt is replaced. when belts jump around during slipping it stresses the auto tensioner weakening it and the slipping also heats the pulleys up more causing the bearings to fail.

 

[ToxicTrav117]

over time the rubber dries out,it has petroleum based oils in it and they evaporate out with sunlight and heat over time causing the rubber to get harder causing slips then the rubber gets working "glazed" becoming even harder(usually in a section of the belt) , it will then get too hot as it slips more resulting in melting. over time it will melt enough to get on the pulleys requiring them to be scrubbed clean when the belt is replaced. when belts jump around during slipping it stresses the auto tensioner weakening it and the slipping also heats the pulleys up more causing the bearings to fail.

So you think I should just get a new belt and go from there?

 

[cookies]

inspect the pulleys, tensioner and bearings, if the pulleys spin like a roller skate wheel the bearings need grease in them, pulleys should be checked for wear and rubber or debris imbedded..betting there is a belt tension spec too.

 

[cookies]

my description is a generic one to try to cover any design of belt system, I left out sheathed belts..nylon/kevlar etc these tend to eat pulleys esp grooved ones. There are small cheap tools used to measure the v grooves in pulleys for excess wear that causes the belt to ride too far down in the groove resulting is slippage. I'll see if i can find a video on it.

 

[cookies]

 

[cookies]

 

[cookies]

this guy goes into detail on using the gauge and figuring out your type of pulley

 

[Del_]

One rule of thumb for belt tension is that between the two pulleys the belt when pushed hard by hand deflects one belt thickness.

Are sure it isn't the hydraulic pump or it's belt that is squealing?

 

[cookies]

pulley alignment video on a truck but the principles are the same

 

[ToxicTrav117]

I rule of thumb for belt tension is that between the two pulleys the belt when pushed hard by hand deflects one belt thickness.

Are sure it isn't the hydraulic pump or it's belt that is squealing?

I'm fairly certain it's the main drive belt but I will also have to make sure the tension is in spec and that they aren't misaligned. I adjusted the clutch thinking it might have been that but that didn't change anything. When I checked the belt this afternoon it was quite tight. I'm willing to bet it's just an old dry belt that squeals when medium-heavy load is placed on it while chipping.

 

[capetrees]

One rule of thumb for belt tension is that between the two pulleys the belt when pushed hard by hand deflects one belt thickness.

Are sure it isn't the hydraulic pump or it's belt that is squealing?

Or maybe someone could just do it right, look in the manual and set the tension to spec as outlined in the manual.

don't be a hillbilly.

 

[user 159780]

For diagnostic purposes only. Spray the belt to confirm that its actually the cause.