Tensioner pulleys - both flat

Poodlehead

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I just checked/replaced idler pulleys and belts and think I overlooked having a wrong idler pulley. I started it up and noticed a burning rubber smell without engaging the blades.

Looking closer, even though the diagram shows the idler pulleys being the same, shouldn't one pulley be flat and the other V shaped? They're item 28 in the pic. TIA!
 

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ILENGINE

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Mower model number would give us something to compare against. But with the MTD 5/8 or 21/32 pto belt the inside flat is fairly wide. Also most wider than some outside flat sides of some other belts. So they may be runnng two flat pulleys in that area due to the inside V is wide enough to act as a flat.
 

Hammermechanicman

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I have seen an old troy bilt (garden way) mower use 2 flat idlers and no V idler.
 

Poodlehead

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Mower model number would give us something to compare against.
Sorry about that. The #s of the mower are:

MN: 13AQ617H118
SN: 1A233H20280 S/N

It looks like apparently some mowers did have both flat idlers.

The other screw up I noticed is that I forgot to put the PTO return spring on it when I started the mower.

Maybe that is my problem????

Thank you!
 

Poodlehead

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Well I haven't been able to find my #@!* return spring, so I ordered another one. :(

The idler pulley bracket that tightens the PTO belt is loose enough where the entire bracket with pulley will move up and down a good quarter of an inch. Should it have that much play? Maybe that's an issue too?

Thank you!
 

bertsmobile1

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Items # 58 & # 15 are belt keepers and the belt should run between them and the pulley as they are designed to stop the belt falling off the pulley when clutching
Usual burning belt is because the belt is on the wrong side of the keeper
 

Poodlehead

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Usual burning belt is because the belt is on the wrong side of the keeper
I did have the belt on the correct side of the belt keepers, but good thought. I've done some stupid stuff lately... :(

I'm hoping that possibly the return spring #48 missing caused the belt to engage enough to cause the slipping/burning problem.

The only other thing I see is the play in the entire idler pulley bracket when the belt is not engaged. I need to check for play when the belt is engaged.

Thank you!
 

Poodlehead

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I took the PTO belt tensioner assy apart and looked at it closer. On the main plate (62) there is significant wear at the pivot point so I'm going to get a new one. Items 22 are thick washers. I only have one and used 2 thinner washers before for the missing thick washer? Is there something special about the thick washers so I should use them?

Also push nut #7 (712-0229) is not on there and seems like it would make it harder to get the assembly apart if it was used. There is a 1.54" spacer above it that did not make it in the pic, but those 2 items are between the 2 sheet metal pieces. That push nut is about $10 so I am thinking about substituting a flat washer or leave it off. Any suggestions?
PXL_20240507_143456681.jpg
 

Poodlehead

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Latest update:
I got the new plate, but still had a little wobble, so I put a flat washer in where the plate pivots to take up the slack. I replaced the nut that holds that assy together with a lock nut tightened just enough to get the wobble out of the plate and still pivot freely.

When the blades are engaged, the belt system is running smooth, but when I dis-engage the cutting deck belt, it comes off the idler pulley(s).

The belt guards are on, but have to be bent outward when I put the belt on. I'm thinking of buying new belt guards, but if I do, I guess I need to put the belts on with the belt guard/pulleys loose enough so the guard does not bend; then tighten the pulleys/belt guards with the belt in place on the pulleys? If so, that seems like a major PITA to do every time you change a belt.

The manual does not address the idler pulley belt guards, but the belt has to be removed from these idler pulleys to remove the mower deck or replace the belt.

Any suggestions are greatly appreciated!
 
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Poodlehead

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The belt guards are items 15 & 58 in the drawing above.
 
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