RTV1100 fuel blues...

[engie]

Ok, just curious what everyone thinks here.

Has new fuel lines, new stop solenoid, new fuel lift pump, new fuel filter, cleaned and drained fuel tank, cleaned spark arrestor, run it without the air intake, etc...

Cranks perfectly. Idles perfectly. At WOT, it runs perfectly for about 15-30 seconds, then falls on it's face. Can hold WOT and sometimes it will catch back up and go again for another couple of seconds before going stupid again, or it might die. If dies, it cranks right back up, and the process starts over.

One thing I did just notice -- looks like the seal behind the lift pump might be leaking a bit or perhaps even the lift pump itself. Seem like the likely culprit? I guess in writing it that seems obvious, but I've had a half dozen "for sure" culprits on this thing that didn't end up being the actual culprit.

 

[dodge man]

Does it smoke at all when this happens? How many hours on the machine. I'd maybe take a fuel line loose after the lift pump, turn the key on and see if it pumps a steady stream of fuel.

 

[ovrszd]

From what I read, sounds like fuel starvation. Not sure yet tbe cause.

 

[leonz]

It is most likely crap plugging the inlet screen in the tank. kubota's are famous for that

 

[engie]

Inlet was cleaned before, and replace this time. Got about 1500 hours on it. Not sure if it is smoking or not when it happens.

What does the seal behind the lift pump actually do?

 

[David_Kb7uns]

Only time had something like that on the RTV1100, the main fuel line from tank was plugged up and fuel would backfeed to the injection pump through the vent line and would only run when tank was full to the cap, once it dropped down it would run out of fuel and die.

David

 

[JOHNTHOMAS]

My F was doing the same thing. Started dying going down hills when pedal released....down hill only. I had forgot to replace fuel cap later and ran over it and replaced it. I replaced the two fuel filters just before running over lid. After the lid run over mine started doing like yours. I replaced the first inline filter and it still did it. I removed fuel line from first inline filter and wrapped my hand around fuel line and stuck the line into the sucking end of a shop vac and sucked out about a quarter gallon of fuel in 10 second bursts and even reversed the vac to the blowing side for about two minutes in bursts. Ran fine for some hours since but I have backup inline filters ready to replace if/when it does it again. Try it if you have a shop vac, may help.

 

[RjCorazza]

If you have a leak at the fuel lift pump there is likely either insufficient fuel being pumped, or air is being introduced. I guess the end result is the same... I would replace it.

 

[engie]

Well, after the 100mi round trip drive to get it, I replaced the gasket behind the lift pump where I thought my leak was, but just in appearance, as I looked at it closely today when this didn't fix my leak, it appears that the fuel is coming from the "through seal" on the primer mechanism inside the pump itself? Also can't tell if the primer deal is actually working or not. I'm pretty fit to be tied at this point. Guess I can replace the pump, but I want to be dang sure that is the problem before I do. Have thrown a bunch of $$ and time at it to get it wrong thusfar.

 

[engie]

Only time had something like that on the RTV1100, the main fuel line from tank was plugged up and fuel would backfeed to the injection pump through the vent line and would only run when tank was full to the cap, once it dropped down it would run out of fuel and die.

David

LOL, can I not extend that line down to the bottom of the tank and just let it roll? I'm at least 75-80% kidding.