# Drive Belt Replacement - What come next?



## Norgo33 (Sep 11, 2010)

*Drive Belt Replacement - Adjustment?*

I have a Yard Machine Gold, Pedal-Drive Garden Tractor, Model 808H. Transmission is 2 speed (Hi, Low, with Reverse and Neutral). Purchased new in 2003. Used hard and has worked great.

The Drive Belt, part 754-0467, twisted. Severe vibration and very low speed. 

I replaced the drive belt with OEM 954-0467 (new prefix number, but supposedly same belt). Vibration is eliminated, but speed remains very low (less than 1/2 it's former speed) even with the Drive pedal fully depressed. With the engine running at full speed, it's like the transmission is in low gear.

The transmission sounds like it’s OK (no squealing, grinding or clunking). Looking at how power is transmitted from the engine to the transmission there are only two obvious possibilities:
1.	The Variable-speed Pulley Assembly (exploded parts diagram part reference number 5, Part No. 656-0050. But this looks and operates OK. The movable sheave moves easily, no real resistance, and it rotates easily.
2.	The drive belt, itself. It seems too loose, but I never really looked at the earlier belt to make a comparison. It appears the Idler Adjustment Rod (Ref. No. 37, Part No. 747-1127) could be adjusted. And so, I adjusted it. First by about ½”. Obvious improvement in speed, but required pedal pressure seems high. Then I adjusted it the remainder of the available rod threads, about additional ½”, for 1” total. Significant speed improvement; required pedal pressure still seems very high, but on this too, I never really paid that much attention to how much pressure was required when everything was working well.

Does anyone have any helpful insights on this issue and better alternatives to the solution I pursued? What else can be done?


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## dangeroustoys56 (Jul 26, 2010)

Was the old belt still in one piece to compare it to the new one? Old belts stretch a lil bit over time but should get you in the ballpark for needed length.

Usually when i match up belts i go by the belt that was on it ( length/size) - not by what the manufacturer says- my dads 88 MTD broke its deck belt- we bot a belt they suggested and it was way too long( original belt shreaded). 

Now another thing to consider is from the MTD's i own, MTD's run a 1/2" wide belt - not 3/8" ( like other mowers) - that makes a big difference on belt tightness and where it rides on the pullies.

When you adjusted the idler rod it changed the position of the variable pulley - hence the pressure change of the pedal - it also changes the path of the belt ( rides deeper in the pulleys or further out).


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## Norgo33 (Sep 11, 2010)

Dangeroustoys56

Thanks for your response and advice.

The old belt was in one piece, though twisted, gouged, and distorted. I never thought to compare it to the new one. For either length or width. The old belt has been discarded. I have now confirmed that the replacement belt is ½” width. The correct OEM part number was stamped on the belt. And, I purchased it from the MTD-authorized repair/parts facility and the cardboard belt holder was printed “MTD Genuine Parts.”

I’ve talked to two tractor repair service writers and both have said that adjustment of the idle-pulley rod shouldn’t be necessary. It’s there to compensate for a belt that is stretched from use. I’m reasonably sure the pedal is harder to depress than before belt replacement, and the tractor has a lower top speed, but, regrettably, I never really paid that much attention to either when things were going well.

I have since returned the adjustable idle pulley rod to its original position. I’m going to use it and see if it’s tolerable. If not I’ll take it to the local tractor-repair. I’d like to fix it myself. In part because their hourly rate is $85!

Thanks again for your advice. 

Norgo33


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## dangeroustoys56 (Jul 26, 2010)

No problem - glad could help. Owning several MTD's , i figure the reason for their 1" wide belt has to do with the variable pulley setup - its odd because no other tractor i own uses a belt that wide.

My dad owns a 88 MTD and uses my 92 white LT12- we've changed the deck belts 3 times on the 88 over the last few years ( even calling MTD directly) and the belt is still too short or too long ( deck comes on when turning it over) - and i think my 92 is due for a complete set of belts as well. Keeps me busy when i go up there.


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