Lawn tractor wont start in choke, only in low throttle why?

[CrystalLee]

Hi, I have a F725 lawn tractor that for some reason wont start in choke, if I am cranking it and move the leaver down from choke to low throttle it will start. I changed the fuel filter, emptied out tank and got new gas, has new battery. What should a girl try next?

 

[CH4Ohio]

But it does start, right? I have several engines that won't start with the choke on in WARM weather. They only need it for a minute or so in cold weather till they warm up. The "choke" setting is only to help you get a cold engine started. As long as it will start, I wouldn't be concerned that it doesn't start in the "choke" position.

I apologize if I'm not understanding the description of the situation.

 

[TractorGuy]

If it starts at low idle and then runs I wouldn't worry about it.

If you want to investigate further you will have to lift off the rear cover and remove the bolts holding the heat shield over the carb. Make sure it's actually moving the throttle all the way to choke. My guess is it isn't actually closing the choke flap. If that is the case then loosen the cable housing retainer, move the throttle lever to the choke position, and tighten the cable retainer back down with it pulled so the choke flap is closed. Operate the lever several times to make sure the cable housing isn't slipping in the retainer. If it is you can wrap some electrical tape around the housing and clamp it back down to hold it better.

 

[MoKelly]

If it starts at low idle and then runs I wouldn't worry about it.

If you want to investigate further you will have to lift off the rear cover and remove the bolts holding the heat shield over the carb. Make sure it's actually moving the throttle all the way to choke. My guess is it isn't actually closing the choke flap. If that is the case then loosen the cable housing retainer, move the throttle lever to the choke position, and tighten the cable retainer back down with it pulled so the choke flap is closed. Operate the lever several times to make sure the cable housing isn't slipping in the retainer. If it is you can wrap some electrical tape around the housing and clamp it back down to hold it better.

This is excellent advice. This is exactly what was happening with my mower.

MoKelly

 

[bearthebruce]

I have a John Deere 103D riding lawn tractor. In the summer, I have to move the throttle to the choke position, crank for a second, then pull the throttle back to start it. Moving to choke position, primes the carb. Then it will start just fine off choke.

In the fall when I am using it for leaf removal, I find it will only start in choke - the cold air keeps it from lighting off like it does in summer.

I agree with those that seem to be saying, "if it starts, you do not have a problem." I don't think I would go looking to fix this. Just adapt to the machines nature even if it doesn't seem normal!

You do realize every machine is different. I always said in my engineering days, "These things have personalities and just like us humans, we have to learn that personality in order to use the machine effectively."

 

[CrystalLee]

Thanks for the advice, it is a lawn tractor that is used in a care home, so a few people including summer students run it. I'm just worried that they may over run the starter and jamb it up. I will probably pull it apart and see if I can adjust that cable. If that fails I will use the label maker in hopes no one struggles with getting it going lol.

 

[TractorGuy]

A easy way to determine if this is the problem. The air filter intake is located at the right rear corner of the engine cover screen. Lock the parking brake and make sure the pto switch is off. Move the throttle lever to the choke position. Crank the engine and squirt a short blast of starting fluid in the intake area. If it starts the chances are good that the choke plate isn't closing at the carb.

If that is the case don't continue using starter fluid. Fix the problem so it starts normally.

 

[Midniteoyl]

Misadjusted cable or running rich.

 

[CH4Ohio]

I have to put this in the "If it ain't broke, don't fix it" category.

There's nothing wrong with an engine not needing to be choked in order to start. Would anyone rebuild their old car carb and throttle linkages because it started WITHOUT pulling the choke?

 

[cqaigy2]

I have some engines that don't require full choke to start, usually need less choke when it's warmer. The choke is to help to start the tractor engine. If you can start the engine with little choke you should be fine.