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it has a fuel pump on the front of the carb. I put new springs and diaphrams in still no fuel.

tractor runs if you dump fuel in carb.

I blew thru the line is clear

what am I missing?

Thanks in advance.

is it a electric or vac. operated pump if its a van operated then check and see if you have vac. at the pump

Some of these fuel pumps are activated by crank case pressure. Try removing the fuel line from the carb and crank the engine over to see if any fuel is pumping out. Often times there will be air in the pump, and this type of pump will not move air, so you have to purge the air out of it, or prime it to get fuel in the inside of the pump so it will draw fuel from the fuel tank.

do you mean remove the line leaving the carb?

It is a vac type pump.

remove the line going from the pump to the carb and crank the engine see if its pumping fuel

longear said:

do you mean remove the line leaving the carb?

It is a vac type pump.

Click to expand...

No. Remove the fuel line "at" the carb. This will be the fuel line that comes "from" the fuel pump feeding the carb.

sorry I meant leaving the pump.

Thanks for the replies. I finally got back to it.

I removed the line from the pump--- no fuel when cranking.

Do I need to prime the pump?

How do I prime the pump?

Thanks again guys.

To prime the pump I usually remove the fuel line from the fuel tank and take a small tank from whatever is around and raise it "above" the fuel pump and crank the engine until you see the fuel pulsing at the output end of the fuel pump. By having the fuel supply "above" the fuel pump, gravity will prime it.

Have you tried removing the fuel shut off valve on the bottom of the carb sometimes they get stuck.Just spray a little carb cleaner and work the switch till it gets free.Has happened on a couple riders that I've worked on.Hope this helps since you have already cleaned the carb.

thanks for all the help. I finally got back to it. It was a cracked fuel hose. Sucking air in instead of bring fuel from the tank. replaced the hose it fired right up.

It's a good feeling finding out it was something simple, isn't it?

should have used tha KISS method of diagnosing.
Keep
It
Simple
Stupid
:laughing:

I am experiencing same thing....no fuel to carb replaced diaphragm....good vacuum to pump, no vacuum on fuel line side of pump. applied vacuum to fuel line via vacuum pump and fuel line is good. do these fuel pumps go bad?

Yes.
They are just a diaphragm spring and in the better ones a pair of check valves of the cheaper ones 1 check valve.
To verify the diaphragm blow ( mout presssure ) down the crank case line.
You should blow a little the stop. If you can blow continuously down the line the diaphram is bad.
Try to blow backwards down the fuel line, again it should go a little way then stop.

The diaphram is attacked by some carb cleaners and the little brass filter goes through to the back of the diaphragm and "Caening" it by squirting cleaners into it simply pushes the gunk on the filter into the chamber and on to the diaphragm.