Gas not getting to carb of rtz 50

[Mike czok]

I can’t get gas to the carb on an rtz 50. I have changed everything except what I think is the vaccum hose and I have no idea how that works. Gas does does go through the fuel pump.

 

[gary noblit]

Mike,you're leaving out a lot of info for us to analyze...been running? quit while mowing?just changed something?what engine?

 

[Mike czok]

Koehler 22. Last summer it would crank for about 20 seconds or so then stop and would start immediately on the next turn of the key and would run and start perfectly until the next time it sat. New carb new hoses new fuel pump.

 

[gary noblit]

Mike, suggestion: remove air cleaner, give it a 1 second shot of carb cleaner( not starting fluid) down carb throat,pull choke and crank.It should fire within 5 sec. if ignition is working properly.If it fires it may continue to run,choke off..Let run a few mins. and try restart.It should fire again...If it only runs out carb.cleaner and quits you have a fuel delivery issue...Remove fuel line from carb ,be very careful where it's pointed ( into a pop bottle with hose taped in) ,remove spark plug wires and crank (you don't want it to start)...If system is working you should pump fuel.If it doesn't pump then hose is plugged, pump is not working or line is plugged from tank or there is a small hole in line that's sucking air not fuel...It's even possible to have an object in tank plugging pick up line.I've seen many objects placed by children in gas tanks...So if it does pump you have isolated the issue to the carb and that one is on you to repair/replace...let us know how it turns out

 

[Mike czok]

Mike, suggestion: remove air cleaner, give it a 1 second shot of carb cleaner( not starting fluid) down carb throat,pull choke and crank.It should fire within 5 sec. if ignition is working properly.If it fires it may continue to run,choke off..Let run a few mins. and try restart.It should fire again...If it only runs out carb.cleaner and quits you have a fuel delivery issue...Remove fuel line from carb ,be very careful where it's pointed ( into a pop bottle with hose taped in) ,remove spark plug wires and crank (you don't want it to start)...If system is working you should pump fuel.If it doesn't pump then hose is plugged, pump is not working or line is plugged from tank or there is a small hole in line that's sucking air not fuel...It's even possible to have an object in tank plugging pick up line.I've seen many objects placed by children in gas tanks...So if it does pump you have isolated the issue to the carb and that one is on you to repair/replace...let us know how it turns out

Starts with the gas cap off which I don’t understand because it has a vaccum hose.

 

[gary noblit]

Mike, your gas cap has a vent built into it.If it starts with cap off the tank is building a vacuum .Normally an engine will start,run, then build up vacuum and quit.Not seeing a pic ,are sure the hose is not a vent that goes to carb to draw fumes? Another thing I didn't mention: the solenoid on the bottom of carb has to open to allow fuel in.It's a 12v sol. that opens when the key is on.They do get sticky.

 

[gary noblit]

Mike the only I know to test a cap...Let machine run tighten cap .After a couple mins .shut off .Put your ear next to cap and loosen.If you here a hiss there's a vacuum in tank.

 

[Mike czok]

Mike the only I know to test a cap...Let machine run tighten cap .After a couple mins .shut off .Put your ear next to cap and loosen.If you here a hiss there's a vacuum in tank.

I think that is what that hose must be. So do I need a new gas cap. I’m going to attach a picture.

 

[gary noblit]

Mike #2 pic is valve cover.The hose coming out the top is vacuum hose that runs the fuel pump,the black circle shape above it. Gas cap? Try cleaning it. You could run a quarter turn loose to test.Did you test line to carb by unhooking it?

 

[mgonitzke]

That vacuum hose doesn't look like its seated properly in the valve cover, and it almost looks kinked as well. Hard to tell because the pic is blurry.

 

[tkhoffman]

Although the gas cap vent would be a valid issue IF the engine was stalling after a few minutes of running. You State that it runs and restarts fine. Problem lies when the machine sits. I don't think gas tank venting is an issue.
I'm leaning toward the stupid shutoff on bottom of carburetor bowl. You should able to hear that valve click as you put the Key to the Run position. It might be a little gummed up and slow to react after sitting.
Here's a thought and a question to the group....has anyone ever had a clogged gas tank vent where after turning off, would suck/ siphon fuel out of the carburetor bowl? I'm guessing that could happen. With a totally dry Carb, that would cause a long Crank start.

 

[mgonitzke]

Not physically possible. The float bowl is vented, which would equalize any pressure, and the needle is above the fuel level in the bowl.

Long crank before start after sitting is because the gas in the float bowl evaporated out the bowl vent over a period of time.

 

[Mike czok]

How do I fix that?

 

[Mike czok]

It a brand new carb.

 

[Mike czok]

That vacuum hose doesn't look like its seated properly in the valve cover, and it almost looks kinked as well. Hard to tell because the pic is blurry.

Now I am getting gas to the carb but will only start with starting fluid.

 

[gary noblit]

Mike,ya' just got to add more info for us to follow.What did you do that allowed gas to the carb?Does the engine keep running when using fluid or stall out?

 

[-CӞ]

It a brand new carb.

wholly new (vs. rebuilt original)?
OEM? NOS?
aftermarket/knockoff?

 

[Mike czok]

wholly new (vs. rebuilt original)?
OEM? NOS?
aftermarket/knockoff?

Aftermarket

 

[-CӞ]

high variance of QC among aftermarket small engine parts. thus a “new” carb could be problematic.
the factory original carb is serviceable, rebuildable.
one is often better off (time & money ahead, performance too) to rebuild the original carb.
if you’ve still got it, you could sure try that (or give/sell it to a member of this community who will).