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Drive Pully Removal

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5212.5 Hydro. B/S twin opposed motor.

The lower crank seal leaks like a sieve.

I've removed the motor with the double pulley still attached.

Normally, I'd expect a set screw on the drive pulley assembly, but there is none.

Here is what I see. There is an upper and lower, stamped metal pulley on the top and bottom of a 6" or so long pipe. The lower pulley is held to a flange on the end of the pipe with three screws. These screws do nothing to hold the pipe to the crank shaft. I can't see how the upper sheave is affixed. I see no bolts, so I assume it's welded.

The pipe appears to have had a 'key' stamped into the side wall, creating an internal 'dimple' that engages the key way on the crank shaft. There appears to be neither a set screw on the side of the pipe, nor an end bolt.

Is this thing pressed on? If I can use a pulley puller to pull on the flange, once the lower tin pulley is removed, how do I get it back on?

I really hate to use a sledge hammer.

Any ideas?

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I have the same question because I would like to rebuild the engine in my 4212. I drenched it in penetrating oil, but even a crowbar doesn't work. I have a pulley puller, but it's not large enough, I don't think. I didn't have it back then. It wasn't a very important project as it does run, but I let go of it because I don't even drive it that much anyway.

Good Luck! :D

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In the center of the tube about 1/2 way up is a bolt holding the pulley assembly to the motor shaft. Unbolt and hope the pulley assembly will "drop". The three bolts are for holding the lower pulley, and also a spacer for the 38" deck as needed. The 42" had the spacer removed. You can use a puller in the flange only to aid removal. I would spray the top of the pulley with oil to aid removal. The key is stamped into the pulley for torque. Slow and easy as you go. A bit of heat might be needed. Good luck.

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I laid awake one night and figured there may be a bolt up inside. Glad to know it is there. Oil it? It's been thoroughly oiled for the last couple years, much more so this spring, from the leaking seal.

I have an envelope full of gaskets along with the crank seal. The block seal doesn't appear to be leaking. So, I'm thinking I'll let that go for now unless the base comes off easy. I really need to get this tractor back on line as the grass is getting away from me.

I have a puller that may do the trick. I hope heat isn't necessary, as I don't have many options. I do have P.B.Blaster, along with a few light taps with a hammer, may loosen things. Wish me luck.

I'm going in! dOd

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There was a bolt up in there. Predictably, it is installed with a significant amount of torque. But I did get it off. Then.. to my surprise, It just slid right off! I noted that wash water from the degreasing I gave it before removing it from the tractor had found its way into the top of the pulley assembly by way of the key way, noted by the water I poured out of the pulley assembly.

To my great pleasure, the old seal came right of. Installation of the new seal was a snap. Slid it on, then snapped it in place, sort of. The old seal had 'backed out' to the point it was sticking out of the hold. THe new one, once snapped home, was about 3/16" below flush with the bottom of the engine case. There is a lip on the inside of the seal that caught a groove in the case. Nice. dOd

Now if I can just remember where the hoses go. The little fuel pumper on the front of the carb has to ports. In my haste I didn't remember which hose went where. Well... I did determine, during dis-assembly, to remember the orientation.. but then I forgot. wah Consulting my B/S service manual I found a drawing showing the crank case hose goes to the barb fitting on the bottom.

This site is awesome.

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