G16 flooding badly

[slonomo]

I had a similar problem. Went through all the same things as you, cleaned carb, replaced parts, etc etc. Couldn't figure it out. Ended up replacing the carb with an old dirty used one.....fixed the problem.

It seems that these carbs can have defects inside that we cannot see. Maybe hairline cracks, bad casting marks that come apart? Not sure what it was that caused it. All I know is the old dirty carb fixed the problem.

You might ask around, maybe someone has one lying around that you could try. Or find a friend locally that has the same carb and swap their carb to try and diagnose?

[Golf cart guy]

You have to change the oil. The engine has fuel in the crank case.

[TestPoint]

Yeah, I suspect gas in the oil.

Did the finger test on the pulse/vacuum line from the crankcase. I can feel the pressure far more than any vacuum. Best description would be lack of pressure.

Pulled the fuel pump and opened it. Both diaphragms appear intact. Can't visually tell anything about the valves. Can blow air through from both in and out which seems inappropriate. Logic would say that each should only pass air in one direction

Neglected to look at fuel stream which would have probably saved taking the pump down and apart.

Guess I will go buy a new pump but that doesn't explain the large volume of fuel blowing out the carb air intake.

[TestPoint]

New pump arrived. Old one was obviously bad as I could blow air through both the in and out ports.

. . . but . . . I now know where all the gas is coming from. It is coming out of the crank case vent tube between the valve cover and the air filter housing. I guess the crank case is full of fuel diluted oil. Perhaps the failed fuel pump one-way valves coupled with an open suction diaphragm pumped gas into the crank case to the point it is coughing it back up.

Wish I understood that for certain.

Drain and refill in the morning.

[CP241]

Usually the diaphragm in the pump will leak gas into the crankcase if it is cracked, or if the gasket allows fuel into the pulse side if the diaphragm. It will drain right in, if the fuel pump you have can be disassembled it will probably be pretty obvious.

[TestPoint]

All better . . . .

Oil in crankcase diluted by at least 50% by gas. At least I was able to flush the crankcase of any sludge.

Replaced the fuel pump with a claimed OEM Chinese knock off. Looked similar, didn't fit between the mounting holes. Had to drill out the holes a bit and then had to turn the mounting base 90 degrees to clear everything. Otherwise perfect and $12.

The pump would not pull gas from the tank. Used a hand pump to get the filter bowl full then everything worked as intended.

Note to fuel system problems searches: A fuel pump will quickly fill the crankcase if the diaphragm fails. It will then cough it back up through the valve cover into the air filter housing.

Thanks everyone for the comments and commiseration.

[CP241]

Originally Posted by TestPoint

All better . . . .


Note to fuel system problems searches: A fuel pump will quickly fill the crankcase if the diaphragm fails. It will then cough it back up through the valve cover into the air filter housing.

Makes sense. That's exactly what it will do if you overfill.ot with oil too. Yours probably smelled like gas because of the dilution rate so youd think it was just coughing up gas.

[Golf cart guy]

Probably nothing was wrong with the fuel pump as a fuel pump failure is super super rare. Draining of the crank case would have fixed the issue

[alchemy]

Been having the same problem for 3 years (G16). Actually it sat 3 years after I couldn't figure it out and I like my electric one anyway. It actually floods the engine while sitting overnight and it won't crank til I remove the battery cable for safety, the spark plug and then turn it by hand to remove the gas, then change the oil. 3 years ago I cleaned and inspected the carb and needle twice. I think it's the original and the cart was not used much. No change. Of course before I read this thread I did get one of those cheap 30.00 carbs and a 10.00 fuel pump on ebay. Started out great then the next day it started dying then overnight the engine flooded again. I thought I cleaned the lines and everything well enough and put a new filter on beforehand. Anyway, I got the gas out of the cylinder, changed the oil, cleaned it all out more carefully, feeding the lines with clean gas etc. then back feeding them. I put it all back together and it seems to run right except it dies briefly because I'm afraid to leave the fuel line connected over night now so there's a gap in fuel flow at first. I want to install a shut off valve no matter what. One thing I'm wondering is I think the float pin might have been out on the new carb before I took the bowl off. It got lost because I didn't expect it to be out. I put the old one in it and now I'm wondering if I made that 3 years ago and maybe it's too short. I realized if they are too short one end might come out? I think the only thing holding it is the sides of the bowl? I'm still yet to see if it's normal yet from the last cleaning. It ran okay this morning after reconnecting the line but then it died briefly and restarted and ran fine. I took the line off again now while it sits. Maybe I should fill the filter and see if it goes down.

[Dave in VA]

Originally Posted by alchemy

Been having the same problem for 3 years (G16). Actually it sat 3 years after I couldn't figure it out and I like my electric one anyway. It actually floods the engine while sitting overnight and it won't crank til I remove the battery cable for safety, the spark plug and then turn it by hand to remove the gas, then change the oil. 3 years ago I cleaned and inspected the carb and needle twice. I think it's the original and the cart was not used much. No change. Of course before I read this thread I did get one of those cheap 30.00 carbs and a 10.00 fuel pump on ebay. Started out great then the next day it started dying then overnight the engine flooded again. I thought I cleaned the lines and everything well enough and put a new filter on beforehand. Anyway, I got the gas out of the cylinder, changed the oil, cleaned it all out more carefully, feeding the lines with clean gas etc. then back feeding them. I put it all back together and it seems to run right except it dies briefly because I'm afraid to leave the fuel line connected over night now so there's a gap in fuel flow at first. I want to install a shut off valve no matter what. One thing I'm wondering is I think the float pin might have been out on the new carb before I took the bowl off. It got lost because I didn't expect it to be out. I put the old one in it and now I'm wondering if I made that 3 years ago and maybe it's too short. I realized if they are too short one end might come out? I think the only thing holding it is the sides of the bowl? I'm still yet to see if it's normal yet from the last cleaning. It ran okay this morning after reconnecting the line but then it died briefly and restarted and ran fine. I took the line off again now while it sits. Maybe I should fill the filter and see if it goes down.

Cleaning the needle valve will do nothing if it is old, worn or damaged. It needs to be replaced.

If the pin holding the float is missing or installed improperly, it will never run right.