Pushmower Carb leaks fuel

[jrz_dad]

Hello - newbie to the forum here....got a gas leak problem that's driving me nuts (...and sadly that's a short trip!)...

my 2012 push mower (B&S 550E, model number 09P 702 0004 F1) leaks fuel thru the carb - it appears to be coming from the ports and out the filter side opening. By the way, its the plastic carb - I've never seen one of these before so its kinda weird working on it...almost like tinkering with your kids toy or something, ya know?

Some quick history on this mower.

I bought it second hand (cheap) cuz the previous owner said it wouldn't start. I cleaned out the carb using carb cleaner and compressed air - reassembled and nothing...I removed the old fuel line and tried to blow it out - couldn't...ran a small screwdriver in the hose and there was a blockage. it appeared to be a 'chunk' of some sort of gasket or rubber material (a significant chunk by the way - could barely get the screwdriver thru it). So, I replaced the hose, changed to fresh fuel, cleaned the carb AGAIN, and tried to start up - it would run a bit then die. OK, at least some progress...I replaced the main jet only, cleaned AGAIN and tried it...now it runs as long as there is gas...BUT I now have fuel leaking out from the carb (as described above) once it sits for awhile...this continues until the fuel is all gone. I bought a rebuild kit and I've replaced ALL gaskets, replaced the main jet, replaced the needle but not the seat. the parts guy said that since the seat is metal and the needle is rubber, the seat is ok and just replace the needle. I have NOT replaced the float as I tested it by blowing thru it upside down and the air does not flow - I turned it right side up and repeated - it flows freely so I have assumed the float is ok.

I'm sure someone has dealt with this issue before so how about sharing the wisdom and enlighten me as to what I should do next...

Thanks!! James

 

[ILENGINE]

Remove and shake the float to make sure there isn't gas in it indicating a leak. It sounds like the needle valve is shutting off fuel flow, correctly. but just blowing into the fuel inlet won't tell you for sure if it is leaking or not. need low pressure pump to comfirm it being actually sealed.

 

[MRCo.]

You tested the float movement, but if it was a leak it will gain weight and not seal the needle. Submerge the flat in liquid, leave t an hour then see if it took any on. If so replace it. These plastic carbs are going to be fun...

 

[jrz_dad]

I'll test the float - but I have a question: with as many times as I've disassembled the carb, if the float had fuel in it, wouldn't it have been obvious since its an opaque plastic? its just a thought but so far the consensus seems to be "fuel shutoff parts" - so I'll retest as per directions above...Thanks guys!!

 

[jrz_dad]

Ok, replaced the float with a new one - even tested it to be sure it wasn't bad - it tests good. and I'm STILL getting fuel leaking out of the mouth of the carb. I've replaced everything in this carb except the seat...I'm really lost on this one. I did put an in-line shutoff valve in the fuel line to stop the fuel flow - at least THAT works!

Since I have "stopped the leak" via the shutoff valve, I don't plan to work on the carb more (yet) but it STILL baffles me as to WHY this is leaking...is it possible that the seat is the culprit? its the ONLY thing I've not replaced in the carb.

 

[small motor man]

It is probably a seal

SMM