1990 12/38 murray belt slipping

briggs206

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hi everyone. I have a 1990 murray tractor that im having issues with. the problem is that when climbing a hill or pulling a load in high gear (4th-5th) my drive belt is slipping. I replaced the belt with a Kevlar correct size belt. the tension is good and the clutch is adjusted also. It seems the pulley on the trans is not made with a V groove like the crank pulley and that is where the slipping is happening. is this normal for the safety of the trans under loads? the pulley on the trans is just a square groove which seems like the belt fits loosely and wouldn't be able to grip it.... any suggestions?
 

Fish

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On the Murrays, jack up the rear end and examine the metal where the transmission bolts onto, look for stress cracks in the sheet metal. Also, note that the trans has 4 main mounting bolts, 2 at each wheel, there should be one more bolt, on the front side of the trans, to a bracket off of the frame, if that one falls out, could easily explain your problem. And yes, it is best to
use the Murray belt, either actual Murray belts, or the aftermarket replacement.
 

briggs206

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I checked the trans mounts and they are fine. the belt isn't slipping off. it just doesn't want to pull inclines in high gears. the belt I put on is a Kevlar belt also. the tension is good too. my question is why are the trans pulleys not a V cut like a typical v belt pulley? this square cut pulley seems that it would slip no matter what belt is on it or how tight it was. a v belt pulley uses the sides of the belt to grip, if the pulley is not v cut then the belt isn't gripping the with the sides.... just want to know if the murrays are built this way to prevent damage or what.
 

de dee

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my pulley is the same as yours,.I am looking for replacment pully now,. but I want to get a smaller pulley to speed up the tractor as i want to use it for a runa round it is to slow now, I removed the mower,. it is very good as a mobility scooter,. cant walk very much but I can ride all day,. 81 years and still kicking,.
 

Fish

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I checked the trans mounts and they are fine. the belt isn't slipping off. it just doesn't want to pull inclines in high gears. the belt I put on is a Kevlar belt also. the tension is good too. my question is why are the trans pulleys not a V cut like a typical v belt pulley? this square cut pulley seems that it would slip no matter what belt is on it or how tight it was. a v belt pulley uses the sides of the belt to grip, if the pulley is not v cut then the belt isn't gripping the with the sides.... just want to know if the murrays are built this way to prevent damage or what.

So, you are saying that you are not using the correct belt???
 

de dee

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I am saying I have the same pulley as you, flat on the bottem, not a V pulley, it does slip under heavy load, but I want to change to a V pulley and go to a smaller rear pulley to give more speed,as I use it as a mobility scooter now, 81 years and have trouble walking, so I have removed the mower deck, and it is now a mobility scooter tractor,.
 

de dee

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I am saying I have the same pulley as you, flat on the bottem, not a V pulley, it does slip under heavy load, but I want to change to a V pulley and go to a smaller rear pulley to give more speed,as I use it as a mobility scooter now, 81 years and have trouble walking, so I have removed the mower deck, and it is now a mobility scooter tractor,.
I am having trouble finding pulleys localy not too many places have pulleys in stock, I will take a drive out in the country side maybe they will have pulleys in stock,.
 
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