MTD / Briggs engine pulley problems

[lefty]

Briggs: 331777-1107 B1 080320z
MTD 13AS699H088 (TMO-3204601)

Engine not original to the tractor. Someone put this engine in an old MTD.

Some might remember this one from about a month ago. I did some work on the carb and did new spindle and blades.

It's back now with even more problems. The upper deck belt was shredded and wrapped around the engine pulley. The belt guides on the engine pulley were bent as it appears that the belt breaking caused some havoc.

I got under it today and noticed that the bolt and washers that hold the double pulley on are long gone and the pulley has slipped down about 2-3 inches on the shaft. Has anyone ever seen this? I know that the engine is a replacement for the Kohler that was originally on the machine. The person that sold it to the current owner did a swap so maybe the pulley and hardware didn't play nice with the shaft?

I'd also be looking for any tips for removal of this pulley so I can get a closer look at everything and see what else is missing. Although the hardware is gone, she's still on there pretty good.

[38racing]

I had that on my neighbour's all stock unit. I noticed deck belt touching deck. Can't remember if bolt was gone or just loose. The key was worn off the pulley so I had to replace it. She had bought it from a friend so recent history unknown although I now recall that her son had tried to fix a no drive problem. Might have been due to
the loose pulley or he created the loose pulley.

[KE4AVB]

It is likely that they never torqued the retaining screw to spec. When I first started I had a couple to lose the retaining screw just because I zip them up with a cheap impact. I have since always use a torque wrench.

[lefty]

Another thing I just noticed as I'm trying to get this pulley off is that the keyways aren't aligned. Probably off by about 1/4 inch. I was able to unwind the belt from the pulley and am trying to figure out how to get it off but I'm wondering if the pulley keyway is damaged or if it plowed out the keyway on the shaft. That would be bad.

[38racing]

My recollection is that the key is part of the pulley. You should see the indent of the key on the outside of pulley shaft.

[lefty]

My recollection is that the key is part of the pulley. You should see the indent of the key on the outside of pulley shaft.

I do see it. And it's not aligned with the keyway on the shaft. Is it designed to fail on the pulley?

[bgsengine]

My recollection is that the key is part of the pulley. You should see the indent of the key on the outside of pulley shaft.

I do see it. And it's not aligned with the keyway on the shaft. Is it designed to fail on the pulley?

It can shear, yes, (more like it just gets hammered flat until it spins on crank) But to really tell you gotta pull pulley off and look down inside and see if it's still formed where it should be - but as low as pulley is in your picture, I'd say more likely the bit of formed key in the pulley has already fallen out of the crank keyway.. But if it was loose and sheared over due to improper torque then it might explain why it is on so tight, might have some luck if you can lock the crank top side (strap wrench on flywheel?) and pipe wrench on the pulley and twist it back to line up with keyway at which point your pulley just might simply fall right off..

[lefty]

My recollection is that the key is part of the pulley. You should see the indent of the key on the outside of pulley shaft.

I do see it. And it's not aligned with the keyway on the shaft. Is it designed to fail on the pulley?

It can shear, yes, (more like it just gets hammered flat until it spins on crank) But to really tell you gotta pull pulley off and look down inside and see if it's still formed where it should be - but as low as pulley is in your picture, I'd say more likely the bit of formed key in the pulley has already fallen out of the crank keyway.. But if it was loose and sheared over due to improper torque then it might explain why it is on so tight, might have some luck if you can lock the crank top side (strap wrench on flywheel?) and pipe wrench on the pulley and twist it back to line up with keyway at which point your pulley just might simply fall right off..

Wow. That worked perfectly. I went with some rope in the cylinder and a pipe wrench on the pulley. Worked like a charm. Thank you for that. So looks like the keyway on the shaft is in good shape. Looks like the key portion of the pulley took the brunt of it. It's a little jagged on the edges but intact. I could probably file it down and get it back on there. The question is, is that the right thing to do? I also noticed that there's a spacer on the schematic for the machine above the pulley on the shaft. I don't have that here but that may be because this engine is not the original. Do I put this thing back on or should I replace the pulley? If so, do I go with the one specified even though the engine is different? And lastly, as far as the bolt and washer(s) for the pulley, do I check the model of the engine for those? Since it's different than the original engine that came with the machine.

[38racing]

Haven't seen a lot of mtd with kohler engines. Common shaft length is 3 5/32 . For bolt you need the diameter and pitch of current shaft but diameter may have to match original to fit pulley right but that is the standard mtd pulley and would likely have been used on whatever engine was in it and a lot were briggs. length would need to be same as original for same shaft length.
Did you look up that mtd model manual list here?
http://manuals.mtdproducts.com/mtd/Public.do

I see 3 different engine manuals and they are all briggs opposed twins, no kohler.

BUT the IPL does show a variety of engines including the Kohler . However since it only ever shows one spacer, pulley and bolt/washer. Look up the shaft hole size and pitch for the that 33 briggs and same for a 42 series . A 2016 briggs repower shows the 33s with 7/16-20 , 3 5/32.
ipl show pulley as this one.
https://www.bantasaw.com/catalog/viewpr ... ?i=&p=6325
I assume that it says without spacer as spacer is separate part number. There might be pulleys similar with spacer built onto it.

[lefty]

I miss spoke, my apologies. It was a Briggs 18.5 twin. It now has a 20hp single OHV. Thank you. I must have read that off something else and had it stuck in my head. That link looks like the same pulley I have.