New Belt to long?

NorthBama

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was the engine unbolted to get the old belt off if so was it fastened back in the same spot. Sometimes when the pulley is rusted on the engine shaft i unbolt the engine from the frame and slide it back to clear the belt keepers. This would make the belt loose if not back in position. Just searching for clues. looks like the belt is routed correct.
 

darrinster

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I replaced the original engine with a 14.5HP Briggs OHV. Same bolt pattern.
 

NorthBama

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that may be the problem the old engine may have had the center line of the crankshaft closer to the front of the frame just saying i dont know for sure. I ran into that issue when replacing a single with a twin cylinder engine
 

darrinster

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The original was a 20HP Briggs OHV Single, and replacement is a 14.5HP Briggs OHV Single. I don't think they changed the crank position?
 

bertsmobile1

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Well it looks all good to me except that engine pulley.
It could be the flash from your camera but it looks like the pulley is polished right down to the root.
If this is the case the belt will be running too deep which will cause the belt to be slack
I would like to see the first image again (111720) again with the pedal fully backed off and the pedal fully down
 

Luffydog

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Does the Belt have tension on it at all? From the pics it looks like it does. Might have a keyway in the axle missing or sheared. But not sure if that one has it in them.
 

darrinster

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Well it looks all good to me except that engine pulley.
It could be the flash from your camera but it looks like the pulley is polished right down to the root.
If this is the case the belt will be running too deep which will cause the belt to be slack
I would like to see the first image again (111720) again with the pedal fully backed off and the pedal fully down

I have another engine pulley I can try, I'll let you know tomorrow if it helps.
 

darrinster

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I installed the engine pulley from the troybilt bronco and made no difference. The mower starts moving when the pedal is pressed around half way and doesn't really speed up no matter where the engine speed is set.

The belt is 90 1/2 inches long, I'm thinking of buying a MTD belt that is 89 inches long part# 954-0341.

Here are some additional pictures 20180813_093724.jpg20180813_093731.jpg20180813_093736.jpg20180813_094008.jpg20180813_094014.jpg20180813_094017.jpg20180813_094019.jpg20180813_094025(0).jpg20180813_094025.jpg

Here is a video I took of it in action
 
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bertsmobile1

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Thanks for the photos & the video.
But please focus the camera and put it on something solid as they were all way out of focus.
The pulley on the left is worn out so you can toss it for starters.
The pulley on the right does not much better but it is hard to tell as all of the close ups are fuzzy.

From the video the tensioning arm operation looks good
So you are either down to the front pulley is too worn or the belt is too long.

And I will put money on the front pulley.
V belts drive from the sloped sides so if at any time the inner face touches a pulley it holds the sides off the pulley causing the belt to slip.
Both of those pulleys appear to have polish marks on the curve at the bottom which means the belt has been running too deep.
The wear on the drive pulleys is typical of what you see when some one fits standard section belts which is common because they are 1/2 the price of the proper belts.

Is there any reason why the brake linkage is hanging down ?
 
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darrinster

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I had another pulley laying around and it wasn't polished looking but still did not help. You think the lower belt is to short? Not to long? I bought the correct OEM belt. Though I'm really tempted to buy a shorter MTD belt to see if it helps.

I disconnected the brake rod because I've been testing out different things and no reason at the moment to connect it.
 
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