GX255 drive belt

Is the best way to replace the drive belt by removing the clutch from the engine crankshaft. I don't see how else to do it.

Does not have to come off completely but dose have to come down a bit to allow the belt to go in.
Be careful, do not stick you head underneath it and pull down lest you think a cauliflower nose looks sexy :laughing:

bertsmobile1 said:

Does not have to come off completely but dose have to come down a bit to allow the belt to go in.
Be careful, do not stick you head underneath it and pull down lest you think a cauliflower nose looks sexy :laughing:

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On most Deere tractors, if you can get the belt around the clutch after unplugging the wire, you dont have to drop the clutch at all.
There are only a few tractors that don't have enough clearance between the clutch and front axle pivot mount, but I dont think yours is one of them.
The trick is to put the belt around the clutch first, then work it between the transmission pulley fan blades down onto the transmission pulley.
Sometimes the length of the belt can make it kinda tight when you try to work it down between the fan blades, but an OEM belt usually will go on with some patience.
Once you have the belt angled between the blades, rotate the pulley to spin it on.
Then install it into the idler pulleys.
Have been doing it in that order here at the shop and in the field for 21 years.
Getting the clutch to slide can be difficult since the factory doesn't apply anti-seize to the crankshaft before they put the clutches on.
The main reason I recommend this method to DIY guys is because if you loosen the clutch bolt and don't torque it properly, the clutch can wallow out the keyway on the crankshaft and/or break the bolt.
And since the bolt is in the crankshaft, the only way to hold the engine still to torque the bolt, is to remove a spark plug and put nylon rope in the cylinder to dead-head the cylinder and keep the engine from rotating.
Some not-so-professional people will just tighten it with an airgun. If I catch any of my guys doing that, I make them take it back loose and torque it manually. Yes, Im anal about that!
Over the years, we have had bolts break and stuff happen due to overtorqued and under-torqued bolts, so that is why we always torque to specs.
If you over-torque it, you will begin to pull the threads and overstress the torsion washer.
If you under-torque it, it can work loose and wallow out the keyway on the crank.
So if you can work the belt on in the way described above, you will save yourself alot of work!

Will, great reply. Thank you. I am helping the farmer I worked for in high school. He is 87 now, I am 72. I was thinking all along that I had to get the belt over all the fan blades at once. Two final question's and then I'll leave you alone. 1. Do you take anything else apart at the back of the mower like the gas tank for access? 2. His old belt had big chunks missing so I think that's how it got off the tension pulleys. You must have to remove those tension pulleys to get the new belt between the pulleys and the keeper tab? Thanks again.

fargo-guy said:

Will, great reply. Thank you. I am helping the farmer I worked for in high school. He is 87 now, I am 72. I was thinking all along that I had to get the belt over all the fan blades at once. Two final question's and then I'll leave you alone. 1. Do you take anything else apart at the back of the mower like the gas tank for access? 2. His old belt had big chunks missing so I think that's how it got off the tension pulleys. You must have to remove those tension pulleys to get the new belt between the pulleys and the keeper tab? Thanks again.

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You're welcome. Yes, you will have to either loosen or remove the idler pulleys.
You also may have to take one side of the drag link loose to get the belt around it. The end at the front axle is the easiest to get wrenches on versus the end up under the tractor.
The trick is to get the belt as straight as possible so it will stretch as far as possible in order to get it over the fan. On some models, you may have to wedge the belt between the drive pulley and clutch to get yourself a bit more belt length to work with, but it will go over the fan with some patience and creativity!
You don't have to remove the fenderdeck or fuel tank.
The whole job can be done from underneath the machine. Good luck!

If you are on a farm, try standing the mower up on it's rear wheels.
Block off the fuel tank with come glad wrap then put the cap back on.
if it has a wet cell battery that has to come out as well.
It is a lot easier to put the belt on when it is right in front of your face & you are comfortably sitting on a beer crate.
You also get a much better view of what is happening .
My SOP is to pop the front on first & as Will mentioned leave it between the clutch & drive pulleys.
Also start with the parking brake on as this will usually provide enough slack to get the belt in.
The bolts holding the idlers have captive heads so all you have to do is pop a finger behind to keep them in the square.
It is these little things that make JD worth the extra $$
Most will have to be loosened to get the belt past the keepers.
While you are there spin the pulleys and check them for bad bearings or damage.
The flat pulleys wears a lot faster than the V pulleys and a deep enough grove can flip a new belt.

All good advice from you and Will1988. We did get the belt on with a couple false starts like forgetting to get it over the steering drag link. Not as challenging as assembling a gas barbecue grill, but close. This forum is mighty useful.

fargo-guy said:

All good advice from you and Will1988. We did get the belt on with a couple false starts like forgetting to get it over the steering drag link. Not as challenging as assembling a gas barbecue grill, but close. This forum is mighty useful.

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Glad we could be of help and glad you got it fixed. Thanks for letting us know!