Removing the drive pulley from my MTD Yardbug

[tbyers31]

I need to replace the drive belt on my tractor. Attached to the engine's driveshaft is a double pulley. The top pulley is the drive pulley and it's connected via a metal shaft to the bottom pulley, the blade belt pulley. I've removed a 9/16 bolt from the pulley, about 4 inches up the shaft. Yet the pulleys are still frozen on the engine driveshaft. According to the diagram there appears to be a key on this shaft that provides the torque. I cant see it from looking up the shaft. Does anyone have experience removing these pulleys? there's got to be a way without destroying everything. Thanks!

[Harry K]

I'm hoping that it can be replaced without removing the pulley. I have to do the same on my Ryobi (re-badged MTD) but haven't got out the manual yet. The belts (both) should be slack enouth to work over the pulley when when the blades aren't engaged and the tranny is in neutral. Oops. That is for a manual tranny, not sure about a Hydro.

Harry K

[tbyers31]

The manual for the YardBug says that the pulleys have to be lowered to replace the upper drive belt (the lower blade belt can be replaced without moving the pulley). The reason you have to lower the pulley for the upper belt is that there's a guard covering about a third of the circumference of that pulley that looks to be too tight to wedge the new belt in. At least that's what the manual says. This gives me an idea... maybe I can force the belt or bend the guard enough to get the new belt on since the pulley is a bear...

[MLD]

I have a Craftsman and removing the drive belt does not require removing the pulley. The mower deck has to be dropped (a couple of pin removals) in order to get the belt off. Obviously not the same as yours but not that far off. MLD

[DanG]

You will need a gear puller. If the bugger has been on forever and is rust and gunk adhered, you may well destroy the pulley pulling it. Soak everything down with K-release or Kroil type rust buster. Apply the gear puller carefully, it should ease on off. Pay lots of attention to where that 1/2 moon key goes, you'll need it back.

(top posted for your convenience) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Keep the whole world singing . . . . DanG (remove the sevens) [e-mail]

[Harry K]

I was at the small engine shop today on a different problem. Asked him what the charge would be. $110 to replace both belts or $140 if the drive belt is actually 2 belts (it is on some apparently, with an intermediate pulley). Cost of belts $30 each. If I have to remove the pulley to do it, I think the shop gets it. Being a regular customer there though, he cut me a special on the labor cost.

Harry K

[tbyers31]

I solved one problem and caused another...

I was able to get the belt on by loosening the metal plate that stretches the width of the body frame and forms the belt guard. To do this I had to remove both back wheels, two screws on each side of the frame holding the plate, loosen 2 screws from the middle where the plate attaches to the differential, and remove 2 screws where a control cable plate gets in the way of the belt guard moving. Whew!

Had I known this from the beginning, I could have had the belt replaced in an hour.

But here's my worse problem... somewhere in the process (I think tapping on the pulley) I caused an oil leak, out of the bottom of the engine. Did I break a seal where the engine sits on the frame? Will I have to pull the engine completely to reseal it? I'm at a loss how to fix this.

Thanks for all the tips.

[Harry K]

Thanks for the information. Looks more and more like my pocket book is going to do the job. At 70 I don't relish crawling around on the floor and I have no lift.

As to the oil leak. If it is the seal the motor has to come out and all pulleys removed. You can't 'fix' a leaking seal except by replacing it.

Harry K

[tbyers31]

I didn't like flipping the tractor back and forth particularly, but then my wife made the comment she thought it was a manly thing to try to conquer machines and she liked that! Wow! Made my day!

Seriously, though, I'm going to let everything sit, cleanup the oil, and try to see what I've done. Somebody suggested it might be oil flooding the carb from sitting on it's side for so long. I hope so, otherwise I'm back to getting that pulley off.

Thanks again.

[Don Young]

For belt replacements it is sometimes possible to remove the engine mounting bolts and slightly shift the engine to get needed clearance. Don Young

[maradcliff]

I agree your dont have to remove the pulley to change the belt, but those pulleys do have a key in them. once you remove the bolt. apply lubricant to the shaft on the top of the pulley. Then firmly but carefully tap on the inner part of the pulley. Hammer it UP first, then down. DO NOT BEND THE PULLEY. They get rusted on but are not press fit.

Mark

[tbyers31]

Thanks for the tip... you're right, there appears to be room above the pulley to move it up first. I may have to do that at some point.

In the meantime, I cleaned up the oil and it appears my problem was oil in the carburator rather than a broken seal. I'll know more with a longer test.