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Discussion Starter #1
This is a classic problem with Cats, that when the driveshaft bearing on the PTO side goes out the speedo key breaks and half of it gets stuck in the driveshaft.

At this point you need to remove the belt, secondary clutch, and the speedo adapter which is held on by 3 carriage bolts and nuts.

Here are a couple of ways to get the key out of the shaft...

1st try a magnet, it may just slide out.

2nd try a sharp awl with a fine yet strong point, try to poke it into the key and pull the key out, it has worked for me.

Finally, if all else fails, buy a 3/32 inch carbide drill bit, it is the perfect size because it fits in the shaft but it will not remove the square edges. Use a small drill, some air drills are quite small, and carefully allign your drill, and drill out the old key. It will come out in small little shards as they break off. Then when its out (you only need to drill in about an inch) the drilling will be easy, you are done drilling.

Then try fitting your new key into the shaft to make sure it fits, if it doesnt fit take a small allen wrench and push it into the shaft to see what is blocking the way. If needed use a small hammer to hit on the allen wrench to push anything back into the hollow shaft. Then make sure your key fits. The key does not go in half way, it only goes in a little more than 1/3 of the way.

Before you reassemble, it is worth it to make sure your speedometer adapter and or speedometer cable are not stuck. Take the cable out of the adapter, use your new key to try and spin the adapter, it should spin with ease. Also with the adapter off, spin the speedometer cable, you should be able to spin it and hear the speedo clicking.

Another tip I have heard when replacing driveshaft bearings is to drill a couple of small holes into the side of the bearing so that when you grease the speedo drive zerk some of the new grease actually goes into the bearing, extending the life. I have used marine grease because when it interacts with water it acts as a solvent and cleans things up while removing the water at the same time.

I do have a tip about how to do a 15 minute drive shaft bearing swap. You need a special tool though. It is some type of a hydrualic pump or ram that will fit under the tunnel, and spread it left to right.

If you have that tool, loosen up the front suspension retaning bolts, but leave them attatched by a couple of threads. After removing the belt, secondary clutch, and speedo drive adapter, pump the ram to spread the tunnel about 1-2 inches, in other words enough to get the metal bearing retainers out over the tip of the shaft, and enough to get the bearing off the tip of the shaft too. If the bearing is stuck on the shaft, this method may not work, you may have to take the shaft out after all. But if you are able to do this and put the new parts back on, the whole job should take no more than 1/2 hour. And it does help to have the front of the sled lifted off the ground because you will need to do some of the work from underneath the sled.

If anyone else has tips to add or corrections please post them. I did not want to get too model specific, but this procedure should work for almost all cats with a speedo drive and or drive bearings.
 

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to much work. a sharp chisel with light taps will pop the aluminum insert that the key is stuck in right out. grab the broken speedo key and remove it. tap the insert back into the axle. 5-10 minutes max.

I never waste time on bearings. if they dont come. split them. takes 5 minutes to cut the bearing in half and have it fall off the shaft. clean shaft and install new bearing.
 

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What about the the speedo drive, any thoughts on getting the key out of it? I tried drilling one once and couldn't keep it from spining, had to replace the unit!
 

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Discussion Starter #5
Actually right now I have to replace mine, because the entire unit is stuck, it does not spin at all. What you could do to hold it from spinning while drilling is stick an allen wrench in the other end that the speedo cable normally goes in. Stick the allen wrench in a vise if you really need extra grip.

But I still have to say that drilling it out with the 3/32nd bit was super easy, 5 mins and done.
 

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This should have a sticky on it, so it would stay on top. I used the 3/32"bit idea today with success. I need to replace by spedo adapter though/ it will go about half a turn and jam.
 

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Anyone had any experiance doing those on a fire cat with the speed sensor magnet in the shaft? We had to press the bearing off of my buddies F7 and it shattered the magnet. Not sure how you would get it out otherwise.
 

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Got my speedo adapter today, and now the speedo works for the first time in two years. Now there's no snow, typical.
 
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