K301A fuel leak

[SJones]

k301A in a 52 yo 126 this started as a slow drip through the air filter. turning off the fuel shut off stopped it. I set about rebuilding the carb. new seals seat, needle, pin. checked the gap on the tab as per the manual. cleaned the carb. out as well. seamed to work for a while. then started again. at this point I was left with the question is it the float? changed that out for a new one. again it worked for a week. last outting it was good. sat all week no leaks. thought I had it. started it this weekend and turned over nice as usual then quit. tried turning it again only this time it didnt roll over and fuel started pouring out of the filter. shut off the valve, thinking it i just stuck being new float. got it turned over and slowly open the valve and got the engine running stable and good. started mowing the lawn all seamed good. got down in a hole where the carb was on the low side and it just quit. then suddenly fuel pouring out of the filter again. repeated the same proceedure and got it back to a spot I could work on it. I fiddled with that float and such it didnt solve the problem. readjusted the tab on the old float and put it back in and seamed to slve the problem later I realized the ned float was heavier. then even later realized it had sunk. got fuel in it. new float too.

So it sat in the garage but still had that slow drip. fuel valve shut off. came in this after noon and in the last 24 hours almost a quart of fuel dripped in to the container i had catching the drip. it was 20 degrees warmer today than the weekend. remember the fuel valve now has a problem too since it let so much fuel past in the off position. it too is a new replacement. Any ide what is going on? it is defenitly coming through the swat and needle but they where cleaned and new ones installed. float adjust to spec. it just keeps leaking even with the new valve off now. I am stumped. could it be this ethanol laced fuel? the ethanol being a reducer of surface tension .
SHane

Shane

[ol'George]

If the carb is leaking fuel, you either have a float that is full of fuel or some crud under the needle/seat and
if the carb is leaking with the fuel shut off, you also have a defective shut off, or crud under its seat also.
Do you have a a screen in the tank or sediment bowel? I'd put in an inline filter, if not.
Do you use a funnel with a screen in it while filling with fuel? if not get one.
You will be amazed how much shit is in your fuel from the filling station.
All my fuel goes through a filter first in the barrel pump, them a screened funnel.
I have never had crud in my carbs/tanks after i started using a screened funnel over 50 years ago.

[SJones]

I changed out the leaking float. it was full of fuel. but that only solved the streaming fuel leak. the slow drip is still present. the entire carb was cleaned out. including the screen filters in the sediment bowl. The fuel shut off just started over the weekend. wasnt an issue before like the slow dripping leak has been. The fuel is screened.

[West Valley G]

You might have already been here but. It seems whenever I have
experienced the things you describe like it was clean and now it leaks
again sort of thing. I have found that I have junk moving around in
the fuel tank. It will give you fits with the fuel shutoff and certainly
in the carb seat. If you haven't already pulled the tank and gave it
a clean it might be the place to look.

Ken

[finsruskw]

That's what the sediment bowl is for, to collect that crap before it reaches the carb.
A rusty tank will cause a lot of these issues. Time to give it a good cleaning with some muratic acid.

Did your repairs include a new carb kit with needle and seat?
Incorrect float adjustment may also play into the problem as well.

[SJones]

Yes a carb rebuild kit was used with new seats and needles. The float has been adjusted. Might be ob to something with the fuel tank though. Looking in the tank, it looks clean doesnt mean it is. The tank di sit empty where it could air out, thoroughly dryin it out. when I was doing the main rebuild. could it be crud stuck in areas I couldnt see dried out and now is breaking loose from the joslling of the tank with fuel in it. Ethanol is a strong solvent. I am going to have a relook and cleaning of the tank. thinking of it, the sediment bowl did start to collect crud quick considering it was only cleaned in march.

[IHinIN]

I bought a 126 that would leak gas out of the air cleaner after the engine was stopped. The kid I got it from had soaked the carb in cleaner and replaced the needle and seat and he couldn’t get it to stop leaking. I disassembled the carb and when I was blowing air through all of the passages I found that the bowl vent was plugged with paint and crap that had likely settled there when the carb was soaked. Cleaning out the vent fixed the leak.

The opposite happened with my 100 a few weeks ago when I tried to start it the first time after sitting all winter. The last time it was ran last fall, the fuel petcock was shut and the carb ran out of gas. This spring, I was getting no fuel to the sediment bowl or carb with the petcock open. I pulled the tank and flushed it out thinking there was crap blocking flow to the sediment bowl. I loosened the carb bowl and fuel started filling the sediment bowl. That told me that the carb bowl vent was plugged. I blew out the vent and now fuel is flowing fine.

It’s strange how a plugged vent can cause no fuel flow to the carb as well as an overflowing carb.

[Fishman]

Did you check the float drop measurement? I had the same issue and after setting the float drop I no longer have to keep shutting off the fuel valve after each use.

[West Valley G]

Originally Posted by IHinIN

I bought a 126 that would leak gas out of the air cleaner after the engine was stopped. The kid I got it from had soaked the carb in cleaner and replaced the needle and seat and he couldn’t get it to stop leaking. I disassembled the carb and when I was blowing air through all of the passages I found that the bowl vent was plugged with paint and crap that had likely settled there when the carb was soaked. Cleaning out the vent fixed the leak.

The opposite happened with my 100 a few weeks ago when I tried to start it the first time after sitting all winter. The last time it was ran last fall, the fuel petcock was shut and the carb ran out of gas. This spring, I was getting no fuel to the sediment bowl or carb with the petcock open. I pulled the tank and flushed it out thinking there was crap blocking flow to the sediment bowl. I loosened the carb bowl and fuel started filling the sediment bowl. That told me that the carb bowl vent was plugged. I blew out the vent and now fuel is flowing fine.

It’s strange how a plugged vent can cause no fuel flow to the carb as well as an overflowing carb.

Now there is some info a fella needs to put in his memory bank. Thanks
for that.
Ken

[IHinIN]

It just dawned on me that both of those issues were with the same carb on the same engine. I kept the K301 from the 126 and put it in my 100.