I have an A14 engine that has been put into an old Erickson Skid Steer to drive the hydraulics. I've had to do lots of repairs on it including installing a new Carburetor with manual choke. The engine has run fairly well for a couple of years, however when I tried to restart it the other day, it appears that the Carb is flooding. I probably only have less than 20 hours on the carburetor. Engine will start, but as I adjust the choke a bit and/or about 15-30 seconds later, the carb floods. In the fuel sight window, the fuel has filled the float chamber. Looking into the carburetor it is obviously getting flooded with fuel.

Of note, if I remove and clamp off the fuel line, I can start the engine and it will run for awhile until the fuel in the carb is used up.

From what I read here, it could be a carb jet??? Something else that stops the float valve from throttling the fuel? Alternately, maybe a fuel pump that has too high a pressure.

I'm looking for a way to troubleshoot this thing. The engine is a bit difficult to work on given its position in the skid steer.

Can anyone give me any insight on what might be causing this issue and/or give me a way to troubleshoot to find what the heck is going on?

I'm still looking for any insight into how to troubleshoot the flooding issue on the carb. Do I just need to pull the carb off and dismantle/clean it? Ouch ... a pain, but doable.

Looks like you have a leaking needle and seat (float valve).

Instructions for removal of carburettor top to access the needle and seat here: http://datsun1200.com/modules/mediawi ... le=Carburetor_Top_Removal

Then have a look at: http://datsun1200.com/modules/mediawi ... le=Float_Level_Adjustment

Denuto, I had tried removing the top of the carb, but between all the throttle linkages and access issues, I had to put the carb top back on and then remove the entire carb to work on the bench. I was able pull the top again and pull all the throttle linkages off. I got to the needle/seat and all the other ports/jets to clean with carb cleaner. The float bowl was DIRTY!!!

Upon cleaning and reinstalling the carb, I figured out that what I had thought was an inline fuel filter was in fact just a check valve. So, I ordered a fuel filter to add inline with the existing check valve before I test out if the cleaning fixed the issue. Didn't want to pull more dirt into the carb while testing, just to have to pull it all apart again to clean it ... sigh.

I didn't adjust the float as I probably have less than 20 hours on it ... and it was working fine ... until is started flooding.

Dirt will be the cause of the problem, but I should have explained in a bit more detail that the needle and seat (float valve) is in the top cover of the carby and is operated by the float. That is when the float rises it closes of the valve which stops the fuel coming through and when the fuel level drops the valve opens again and the fuel flows (just like a float valve in a toilet cistern). I'll bet your float valve is full of dirt which prevents it from closing, and that's why your carby floods - the fuel just keeps coming.

You'll need to pull the carby top off again. Remove the float and you'll be able to get at the needle and seat to clean all the dirt out. That should fix it and a new filter will help keep it clean.

You are right, that is exactly what I did and what I found. I pulled the carb top off and the pulled the float valve and thoroughly cleaned it until the carb cleaner I was using flowed through it easily and the valve sealed properly. All the "dirt" in the carb bowl is what made me look upstream ... and then I found that I didn't have the fuel filter I thought I had ... just a check valve. Fixing that as soon as the filter arrives in the mail.
Thanks!!!