CT322 starving for fuel. Check valve???

[TonyCT322]

Did my regular service. Now is hard to start or runs great for hours and starts struggling for fuel. Changed filter 3 times. Bought replacement hand primer, housing and filter all in one. Bypassed mechanical lift pump with electric pump. Blew out lines. Doing better but if sits for a few days it is still loosing the prime. Is there a check valve in the system? Parts list shows no filter on the metal pickup tube. When cranking, I am getting blue smoke out of the exhaust. Once started, it runs great. I think I have changed everything I can. Thank you.

 

[foton]

I think you might have a vacuum leak and air is getting to the system if you are loosing prime,and yes there is a check valve in the system it is inside the primer ball. I have no idea on the pick up tube filter, but it is possible that the leak is a cracked pick up tube above the fuel level inside the tank. I just had to replace mine recently because of this.

 

[TonyCT322]

Good thought. I dread taking the pickup tube out. It looks like the alternator and maybe ac compressor need removed to gain access. The parts diagram shows it as a metal tube, so probably very little flexibility for maneuvering it out. The entire primer unit is new. I picked up new fuel line today and will replace that while I am in there. Thank you

 

[foton]

if it is a metal tube I would lean towards there is a filter on the end that is plugged up, mine was a soft rubberish pick up with a weight on the end so it swings around pretty good I imagine.

 

[SkidTracks]

You could have an electric fuel pump with very fine silt / dirt inside of it. Keeping the pump's check valve from seating properly.

Strange though it runs for hours then struggles for fuel. Two possibilities, come to mind.
The tank fuel level gets low enough, the fuel pump has trouble lifting fuel with slightly leaking check valve.
Fuel is getting sufficiently hot to cause vapor problems with a weakened fuel pump.

On a fuel problem I had, I temporarily strapped a 5-gallon diesel jug to top of cover of engine. Then connected a 12v diesel fuel pump from diesel jug to fuel filter intake. Got machine moving.

You might try similar to temporarily bypass machine's tank, internal pick tube of tank, and machine's 12v fuel pump. Machine still has fuel problems, you will know it's from fuel filter onward into engine. No problems and its from fuel filter back to tank.

 

[Kenskip1]

mistake

 

[mg2361]

Is there a check valve in the system?

Yes. The barbed fitting that comes out of the block that leads back to the tank.