# Strange MTD Lawn Tractor Problem



## deandome (May 2, 2010)

(all manual tranny, etc). Model # is TMO 3100002 (here's the manual, if that helps: http://manuals.mtdproducts.com/mtd/DocGetter?doc=770-8087h.pdf )

Anyhow, I got it out for the first time this year a few days ago, it fires up fine (as it's done for the 10 years I've owned it), and I cut the front yard fine. Right at the end of that, I hear the motor bogging down/conking out, sounds like it does when it runs outta gas, so I raise the deck/disengage the mower & turn it off.

There was gas left, but I add a buncha fresh gas to top it off...start up and it runs fine (full RPMs, it's not old gas or anything), UNTIL I try to engage the mower...then it bogs/dies.

Figuring it might be a problem w/the deck (bad bearings causing lotsa friction or something), I remove the deck & the belt completely.

Here's the mystery part....it STILL bogs down & dies, even though the deck isn't sucking any 'power' from the motor!!! It doesn't matter if you're in park or driving, it just bogs/dies (I always disengage before it actually dies, though).

Does anyone know what this might be...what I should check? The belts are old, but they seem fine, and the main double-pulley below the engine (that drives the deck & the transmission) isn't even driving anything when it bogs/dies (no deck/in park)!!! I can't see, or even imagine, how moving the mower deck lever could effect the engine, if the mower isn't even on the tractor!

Any help would be appreciated..THANKS!


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## Windlake (Apr 29, 2010)

Clogged fuel filter? Gas cap vent plugged?


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## Taelwind (May 7, 2010)

If it was a clogged fuel filter or stopped up gas vent, the mower would run for a short while then die, the fact that it bogs down under load, suggests something else. 

If the only time it bogs down is when you lower the handle to engage the deck, (and the deck is not installed ) would lead me to believe that one of the safety switches is bad. For example, if the mower is in reverse, and you try to engage the deck, the mower will die. This is a safety feature that prevents one from mowing over flowers, loved ones, into a ditch causing roll over, a family car, etc., etc.

I would disconnect the wire that connects near where the F/R mechanism is attached. On older MTDs this in the panel you see when your sitting on the mower. On later models, it is on the fender. 

Sometimes the safety switch on the seat goes bad, and that can trigger the same problem. The fact that the mower runs when the brake is depressed, means that the safety switch for the brake is OK. If you disconnect ( not remove ) the two safety switches wires, and you continue to have this problem, ( assuming the mower is in neutral and you continue to have this problem - then look for a short in the wiring harness - ha ha:lmao: have fun with that one. :dazed:

Good luck ( this message will self-destruct 15 seconds before you need it the second time around )


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## Hoodoo Valley (Nov 14, 2006)

deandome said:


> (all manual tranny, etc). Model # is TMO 3100002 (here's the manual, if that helps: http://manuals.mtdproducts.com/mtd/DocGetter?doc=770-8087h.pdf )
> 
> Anyhow, I got it out for the first time this year a few days ago, it fires up fine (as it's done for the 10 years I've owned it), and I cut the front yard fine. Right at the end of that, I hear the motor bogging down/conking out, sounds like it does when it runs outta gas, so I raise the deck/disengage the mower & turn it off.
> 
> ...


Soooo, does it bog down if you, say, pull a heavy load or is it just tied to the PTO only?


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## flman (Mar 23, 2010)

x2 on the safety switches.


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## detel51 (May 23, 2010)

Don't rule out the choke!


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## Hoodoo Valley (Nov 14, 2006)

deandome said:


> (all manual tranny, etc). Model # is TMO 3100002 (here's the manual, if that helps: http://manuals.mtdproducts.com/mtd/DocGetter?doc=770-8087h.pdf )
> 
> Anyhow, I got it out for the first time this year a few days ago, it fires up fine (as it's done for the 10 years I've owned it), and I cut the front yard fine. Right at the end of that, I hear the motor bogging down/conking out, sounds like it does when it runs outta gas, so I raise the deck/disengage the mower & turn it off.
> 
> ...


Have you made any headway in figuring it out yet?


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## billmoran (Jul 15, 2014)

murray engine runs but with a lot of mis fires or backfires how do i fix that?


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