Kohler Command V-twin. Cranks but no-start.

outdoorpowermike

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Put vac gauge on suck port, should have -1.5 reading red side, put gauge on push port going to carb should have +1.5 reading green side. Test shows good pump is good. Ck for pulse any movement good. Ck for clog from tank to pump, ck power to carb solenoid and ground.
 

outdoorpowermike

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Put vac gauge on suck port, should have -1.5 reading red side, put gauge on push port going to carb should have +1.5 reading green side. Test shows good pump is good. Ck for pulse any movement good. Ck for clog from tank to pump, ck power to carb solenoid and ground.
 

firhill

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Put vac gauge on suck port, should have -1.5 reading red side, put gauge on push port going to carb should have +1.5 reading green side. Test shows good pump is good. Ck for pulse any movement good. Ck for clog from tank to pump, ck power to carb solenoid and ground.
Yes. Your replies are there. Thanks.
Carb solenoid has 12v in run, will check for 12v in start too.
Fuel pump is new
Pickup, filter and all lines are not blocked or clogged in any way.
Thus, I suspect no vacuum from crankcase.

Too hot still, to check. But will post back when I do.
 

outdoorpowermike

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Thanks, To hot? Remember that our military folks are wearing a lot of heavy stuff in temps much hotter. That's hot. Just sayin. Please let me know outcome.
 

firhill

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Finally got back around to trying to figure this out.

I installed a 12v electric pump (2-4 psi).
Engine will stay running but surging and only if I keep the choke on and hold the pump up above the height of the carb.

Switched back to vacuum fuel pump and for some reason the vacuum is now much stronger, to the point where it draws fuel from the tank and trickles out at pump output but still won't push it all the way to the carb.
The carb sits a touch higher than the fuel pump so I again held the vacuum pump above carb level and again the engine runs but sputters and sometimes stalls.

About to park it until next year and just use the Craftsman YT4000.

Too bad because I love the zero turn and how much faster it does the job.
 

Auto Doc's

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It sounds like the vacuum operated pump is defective or some trash got sucked into the inlet side from the tank. I've had lots of strange issues in the past Even a bug looking for a place to nest will find their way inside of an open fuel line end.

I noticed line spring clamps out of place earlier. The clamps must be in place and tight so a line will not suck in air. Spring band clamps typically work but I prefer the worm drive screw type.
 

firhill

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It sounds like the vacuum operated pump is defective or some trash got sucked into the inlet side from the tank. I've had lots of strange issues in the past Even a bug looking for a place to nest will find their way inside of an open fuel line end.

I noticed line spring clamps out of place earlier. The clamps must be in place and tight so a line will not suck in air. Spring band clamps typically work but I prefer the worm drive screw type.
Thanks Doc. I did replace all the spring clamps with ring clamps.
Lines are are new from gas tank to fuel pump I'll switch back to the original vacuum fuel pump one more time.
I'll also try leaving the fuel filter out just incase that's slowing down the flow.
 
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