FR691V loses power after getting warmed up

Lawnpear

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Anytime i go to cut the grass it runs great for like 20 minutes then starts to act really weird. It looses power, surges, sometimes only runs with choke. This only happens when its running for awhile. Seems to be getting too hot. This has been an ongoing problem for 2 years now. I took it in last year, the shop did a full work up and ending up rebuilding the carb. Costed me $500. It did finish the season well though. I take it out this year running great 5 cuts into the year it starts doing the same thing. Instead of paying $500 again i took it into my own hands to buy the $225 carb and replace it myself. Cut the whole lawn (2 acres) but started acting up as i was driving it back to the shed. Started surging and died 3 times before getting into the shed. I fired it back up this morning and like clock work 20 mins in boom acting up and losing power. Any help would be much appreciated thanks!!!
 

Rivets

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Next time it starts to happen quickly open the gas cap and see if if goes away. If it does replace the cap. Alot cheaper than throwing a carb at it.
 

Lawnpear

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Thanks but that turned out not to be the problem. Yesterday after i fired it up again (all cooled down) to finish the rest of my grass and it started to do the same thing but it was running super rich. When i shut it off a siphon started and fuel came pouring out Of the exaust. Maybe a bad ignition on one of the cylinders?
 
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Rivets

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I have no idea of what you mean by "a siphon started and fuel came pouring out of the gas tank".
 

Lawnpear

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Hear me out. So these engines work off of a pulse fuel pump. So when the engine was off fuel just started pouring out of the exaust. So there for it had to be siphoned. Theres no way fuel should be able to pour out of the exaust. I dont get it. I checked the valves and they seem fine.
 

Rivets

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If fuel is coming out of the exhaust, your problem is a bad float needle and seat in the carb. It is not controlling the amount of fuel in the float bowl, shutting off properly. Time to remove the carb and rebuild or replace. If you try to do this yourself, you will end up replacing, as these are not easy carbs to rebuild, even by a seasoned tech. By the way, it is not siphoning fuel from the tank, just allowing the overflow to exit the engine through the exhaust.
 

7394

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The electric solenoid that shuts off the main jet in carb can be audibly tested, by listening at the carb (engine off) & turn key to on position (not start) you should hear a mechanical click, which would be the solenoid shut off in carb opening. Turn off key & should be able to hear that too in the carb.

PS: When is last time you removed engine cover to see if the fins etc are clean & free of debris ? Reason, it sounds like you are possibly overheating.
 

bertsmobile1

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The electric solenoid that shuts off the main jet in carb can be audibly tested, by listening at the carb (engine off) & turn key to on position (not start) you should hear a mechanical click, which would be the solenoid shut off in carb opening. Turn off key & should be able to hear that too in the carb.

PS: When is last time you removed engine cover to see if the fins etc are clean & free of debris ? Reason, it sounds like you are possibly overheating.

The fuel solenoid shuts off the supply to the main jet.
IT does not stop the float chamber from overfilling and then leaking out of the bowl vent, into the carb throat then down into the engine which is what is happening.
 

FLRon

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Anytime i go to cut the grass it runs great for like 20 minutes then starts to act really weird. It looses power, surges, sometimes only runs with choke. This only happens when its running for awhile. Seems to be getting too hot. This has been an ongoing problem for 2 years now. I took it in last year, the shop did a full work up and ending up rebuilding the carb. Costed me $500. It did finish the season well though. I take it out this year running great 5 cuts into the year it starts doing the same thing. Instead of paying $500 again i took it into my own hands to buy the $225 carb and replace it myself. Cut the whole lawn (2 acres) but started acting up as i was driving it back to the shed. Started surging and died 3 times before getting into the shed. I fired it back up this morning and like clock work 20 mins in boom acting up and losing power. Any help would be much appreciated thanks!!!

I'm having the EXACT SAME SYMPTOMS. Just started today. Mower has 9 hours on it. Would like to chat with you via email or phone to try and help each other.
 

bertsmobile1

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I'm having the EXACT SAME SYMPTOMS. Just started today. Mower has 9 hours on it. Would like to chat with you via email or phone to try and help each other.

Please keep it on the forum.
That is why it is an open forum so people with the same or similar problems can read up on the fix and try it themselves.
 
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