Kohler CH22 starving for gas

[Robert Boudreau]

Status report: I have finished all the work, cleaned the engine, checked the wiring, fuses and cleaned all wiring connections. Started the mower (I noticed a little surging - though not consistent) and mowed for an hour or so. The mower was running good. Then it shut down. I checked the ignition switch/wiring. It was cool. I noticed a small amount of white smoke - not much. With the mower outside under a noon sun, the lighting was good. To late to be brief.....but, what I discovered was a leak down around the breather cover cover. However, it was not leaking from the breather gasket. To me, it looked like it was a possible combination of oil and gas. I say that because the fluid was neither clear or dark (like dirty oil). Again, the fluid (that I could see) was on the top/backside of the engine (as in above the coils).
My guess (I am not a mechanic) is that the engine is running hot and shutting down. I believe this accounts for the lack of visible gas in the fuel filter - once the engine was started (especially since I had previously eliminated all other possible fuel issues).
With this said, I am wondering if I have a head gasket leak??? Would that account for a possible vacuum leak (accounting for the lack of gas issue)???

 

[slomo]

I removed the fuel line going to the carb and placed it in a container. I then turned the key. The pump was pumping gas thru the line into the container. So, the pump is working.

Like this video? I would replace all three fuel lines. Bet one of yours has a crack in it.

 

[slomo]

replaced all fuel lines including the rubber grommets on each saddle tank

Meaning the incoming fuel line, impulse hose off the block and the output line to the carb inlet right? 3 hoses on the fuel pump.

From what you are saying, you have a fuel delivery issue. Your filter is empty and engine shuts down.

If you've cleaned the tank and outlet, installed new hoses and filter and still have no gas, you have missed something. Gas cap opened to check for a non vent condition which will cause no fuel flow from the tank.

Did you pressure test the carb?

 

[Auto Doc's]

Hi Robert B.,

There is a pulse type fuel pump that has the 2 fuel lines (supply and carburetor) and then a 3rd line for the crank case pulses to operate the pump. Check that line and make sure it has not split or coming apart so that it is barely hanging on.

This is not an engine head gasket issue. That will not come and go like you are describing.

I rule out the ignition coils also, because they do not just quick working at the same time.

 

[Etbrown44]

Since you've spent countless hours on this and replaced or checked numerous parts without success, I'd try a new carb. That is assuming you tried a new temp aux tank and did replace all 3 fuel lines.

 

[WilliamLPloetz]

What fuel filter are you using? And how did you verify the vents are working properly?

Have you cleaned out the fuel tank? I had an old John Deere 318 that I picked up cheap that did the same thing. Turned out there was a huge amount of sludge in the bottom of the tank that was restricting fuel flow. Cleaned out the tank and that took care of that problem. May not be your problem but could be worthwhile to check it out.

 

[Freddie21]

Anti-fire solenoid? I know you rebuilt carb, but was the solenoid replaced? Run with spark testers on it. Run with kill wire TEMPORARLY disconnected to verify safety switches.

 

[Catenary Kid]

Robert,

I had the identical problem with a Simplicitith an 18 HP Briggs Vanguard. I tried everything and so did the dealer. I finally solved it by selling the mower. Sorry I don't have better news...

Al

 

[bentrim]

You did not (at least what I read) the make of the mower. I will state what I have found on Gravely Z turns. There is a steel fitting that pushes thru a bushining into the fuel tank. On the other end of that fitting is a flexible hose that is pushed onto and special clamped onto the fitting. As the hoses age the deteriorate and crack and some have even fallen off. So if you have this type of tank i9t may be a palace to check. Note there is a fine screen strainer on the other end of the hose.

 

[g-man57]

Sorry, but I didn't read all the posts... But my theory of small engine repair - or any engine repair - is, check the simple things first. You said you did check the fuel venting... But I'd run it with no fuel cap and see if it still dies. It does sound like you're getting a vacuum in the fuel system.