Mower engine hot start issue

[slowindown 494]

I have a 2013 54” hustler fastrak. I’ve had it since new. It has a kawi 23hp fs691v engine. It currently has ~1000 hours. It runs fine except:

 

over the last 2-3 years I’ve noticed that if I accidentally run it out of gas when it’s hot or turn it off with the throttle on high when it’s hot it will not restart until it cools down. No amount of starter fluid or choking will make it start until it’s cool. 
 

Nothing has ever been done to the engine aside from regular oil and air and oil filter changes and I changed the spark plugs and fuel filter last year. 
 

Thoughts?

[jeepwm69 7,749]

Does it have one of those weird fuel solenoid shut offs on the carb?  @basfnb had a JD mower that was screwy like that.

[slowindown 494]

I’m out of town but found this internet pic and it appears to have a big wart on the bottom of the carb bowl. 
 

 

[Melatv 797]

You may have to adjust the valves

[56Sierra 1,845]

16 minutes ago, slowindown said:

I’m out of town but found this internet pic and it appears to have a big wart on the bottom of the carb bowl. 
 

 

Warts are never good.  Especially the type with wires coming out of them.

[slowindown 494]

Yeah I’ve never adjusted the valves. Found one reference with a similar issue on a mowin site that turned out to be a head gasket.

 

When I accidentally cut it off when hot without letting it idle first, I can force cool the engine and get it to crank. 

Edited April 30, 2021 by slowindown

[Misterclean 420]

I've been working on these things for 38 years. I must say those are some odd symptoms. Perhaps its flooding when not running? If it's tight valves I would suspect it would run poorly when hot. Best thing is to check spark when this happens and work down from there. Could adjust valves to be sure. I very curious myself. Please keep us posted.

[Fishfiles 20,147]

6 hours ago, slowindown said:

I have a 2013 54” hustler fastrak. I’ve had it since new. It has a kawi 23hp fs691v engine. It currently has ~1000 hours. It runs fine except:

 

over the last 2-3 years I’ve noticed that if I accidentally run it out of gas when it’s hot or turn it off with the throttle on high when it’s hot it will not restart until it cools down. No amount of starter fluid or choking will make it start until it’s cool. 
 

Nothing has ever been done to the engine aside from regular oil and air and oil filter changes and I changed the spark plugs and fuel filter last year. 
 

Thoughts?

My last Husqvarna with a 25 Kohler did that same thing , if , I didn't let it cool down on idle for about one minute before killing it ----try that next time , when you are   finished mowing ,  let it cool down running at the lowest idle for at least a minute before killing it 

[slowindown 494]

29 minutes ago, Fishfiles said:

My last Husqvarna with a 25 Kohler did that same thing , if , I didn't let it cool down on idle for about one minute before killing it ----try that next time , when you are   finished mowing ,  let it cool down running at the lowest idle for at least a minute before killing it 

That’s what I’ve been doing for the past couple years when I need to cut it off to gas up or re-beer. Actually I only let it idle maybe 15-20 seconds before cutting it off and it’ll fire back up. I usually mow anywhere from 3 to 5 acres with it. 

[LedFTed 1,142]

i want to put a starter assist relay on the zero turn. properly installed, it leaves the safeties still working. it cost maybe 20.00, with a spare fuse.. the zero turn eats up the starter relay. the cause being, not enough voltage to the relay, that comes with... i got mine on amazon..,, before ya buy one, look it up online..

[LedFTed 1,142]

could it be vapor lock?

[shadetree 5,970]

the fuel cut-off solenoid on the bottom of the carb is bad, replace it, problem solved.

[slowindown 494]

2 hours ago, shadetree said:

the fuel cut-off solenoid on the bottom of the carb is bad, replace it, problem solved.

When I’m back home I’ll order one and definitely try that.
 

If that don’t fix it, after the mowing season I’m going to unbolt the engine, spin it where I can get to both heads and replace the head gaskets and adjust the valves. My thought has been that because of the symptoms I described above and the remedy (cooling the heads), that when it’s super hot there’s not enough compression to start. 
 

here’s a pic from the head gasket of one with the same engine with what was described as an identical  problem 

 

I don’t seem to have any other symptoms of a blown head gasket though. 

 

 

Edited July 3, 2021 by slowindown

[shadetree 5,970]

6 hours ago, slowindown said:

When I’m back home I’ll order one and definitely try that.
 

If that don’t fix it, after the mowing season I’m going to unbolt the engine, spin it where I can get to both heads and replace the head gaskets and adjust the valves. My thought has been that because of the symptoms I described above and the remedy (cooling the heads), that when it’s super hot there’s not enough compression to start. 
 

here’s a pic from the head gasket of one with the same engine with what was described as an identical  problem 

 

I don’t seem to have any other symptoms of a blown head gasket though. 

 

 

i have owned my craftsman 42 inch cut, 17.5 hp ridding mower sense 1996, i know for a fact how the solenoid works. there is a ton of mis-info on the net how these work. one says it prevents blow back from turning off the engine on high rpm's, which explain why they say to idle the engine down first before turning the engine off. i have also read/watched other video's explaining how these prevent fuel from filing the float bowl up, and fuel not reaching the main jet. this is NOT a valve adjustment issue, i say this, because i have yet adjusted my valves on my mower from the day i bought it in 1996 ( although they should be checked/adjusted ?!..lol ), i can run my mower for over an hour at full speed, shut it down, and it will crank right back up. my money say's replace the part under the carb. MAKE SURE YOU INSTALL AN INLINE FUEL CUT-OFF VALVE ON THE FUEL LINE IF IT DOES NOT HAVE ONE ?. P.S. you can test MY theory by unplugging it, try cranking it to start it, i bet it wont start at all ?, i have tried this on mine, if unplugged ?, it will not start and run, once i plug it back end, turn the key on, i watch the plunger open, this opens the fuel to reach the main jet.

[slowindown 494]

Thanks shadetree. We’re at a campground for the 4th but I’m planning on running by the house today for a bit. I’ll unplug it and see what happens. 
 

By the way, if I didn’t mention earlier, I bought this mower new in 2013. It now has a bit over 1000 hours but I remember it doing this for at least the last 3-4 years on occasion. 

[shadetree 5,970]

3 hours ago, slowindown said:

Thanks shadetree. We’re at a campground for the 4th but I’m planning on running by the house today for a bit. I’ll unplug it and see what happens. 
 

By the way, if I didn’t mention earlier, I bought this mower new in 2013. It now has a bit over 1000 hours but I remember it doing this for at least the last 3-4 years on occasion. 

if you get the time ?, yes, unplug it on a cold engine, try starting it, if it wont start at all ?, plug it back in, then try starting it, i bet it wont start at all unplugged, and on a cold engine without it plugged in ?. let us know !.

[slowindown 494]

1 hour ago, shadetree said:

if you get the time ?, yes, unplug it on a cold engine, try starting it, if it wont start at all ?, plug it back in, then try starting it, i bet it wont start at all unplugged, and on a cold engine without it plugged in ?. let us know !.

I unplugged it. It started and immediately died. It would not start back unplugged.  I plugged it back in and it started. I unplugged it while it was running and it died. I plugged it back in and it started back up.

[shadetree 5,970]

3 hours ago, slowindown said:

I unplugged it. It started and immediately died. It would not start back unplugged.  I plugged it back in and it started. I unplugged it while it was running and it died. I plugged it back in and it started back up.

yep, thats how they work !. it will not run with it unplugged very long..if at all ?. i say replace it, run it until hot, shut it down, see if it cranks back up ?.

[slowindown 494]

20 minutes ago, shadetree said:

yep, thats how they work !. it will not run with it unplugged very long..if at all ?. i say replace it, run it until hot, shut it down, see if it cranks back up ?.

Yikes! That little doodad is over $100.  I may try a cheap $10 one and if it don't work cut the plunger off of the cheap one to bypass it to make 100% sure that's the problem before dropping $100 on that little thing.

[shadetree 5,970]

36 minutes ago, slowindown said:

Yikes! That little doodad is over $100.  I may try a cheap $10 one and if it don't work cut the plunger off of the cheap one to bypass it to make 100% sure that's the problem before dropping $100 on that little thing.

yeah, they are not cheap. you can find them all over ebay cheap. you can cut the tip off the one on there now, just be sure to have an inline cut-off on the fuel line from gas tank. try one from ebay before you go cutting any tips off though.

[slowindown 494]

Will do. I ordered one of the cheap ones. 

[shadetree 5,970]

2 hours ago, slowindown said:

Will do. I ordered one of the cheap ones. 

great, keep us updated !.

[LedFTed 1,142]

Edited July 5, 2021 by LedFTed
cancel., not what i wanted to post

[LedFTed 1,142]

the 1st pic. is not what i wanted to post. the 2nd is... i intend to install this on the ex-mark zero turn. its out of warranty,  an i have been through plenty of solenoids with this creature. when its hot, is the worst. wont start, have to get a charger. so i got a boost to the battery an now the battery will turn the starter, to fire the motor.

i ave already tested this, with a jumper start button, just hook up 2 wires, one goes to the battery, the other goes to the solenoid. gives extra strength from the battery, more voltage, or current. i have always jumped battery voltage to the plus terminal on the solenoid, and didnt know any other way. till of late. i was afraid to use my push button  jumper, across the battery terminals at the top of the solenoid.

[jeepwm69 7,749]

On 7/3/2021 at 11:17 AM, shadetree said:

the fuel cut-off solenoid on the bottom of the carb is bad, replace it, problem solved.

 

I hate those things.