Need to prime a fuel system

[Pebs]

200 800 RMK

So I'm finally getting ready to test fire this thing. No exhaust sytem built yet, I just wanna hear it fire so I can move on. I have the oiling system primed and ready to go. I need to prime the fuel system since the tank ahs been flushed, lines are new, new filters, new on/off valve, rebuilt pump...it's all new or rebuilt. This thing frickin sucks to pull over. I wanna minimize as much cranking it over as possible, so I need to prime my fuel sytem. Whats the best method of doing this? Do I need to pull the float bowls and hold the floats down or what?

 

[alsled]

Blow as hard as you can into the tank vent with gas cap on, and you'll see the lines fill in seconds, carbs will take care of themselves in another few seconds.

Or blow into the gas filler neck.

 

[speedytoes]

Pebs -

Is this a 2 stroke? If so. . . with no exhaust system. . . well, actually, with no "correctly designed" exhaust system, you'll be lucky to get it to run at all, let alone run decently. The exhaust on a 2 stroke is essential to running, not just performance.

My engine has both mechanical and electrical fuel pumps, so is "primed" when I throw the switch to activate the electric fuel pump. When the carbs stop accepting fuel, it returns (though a smaller orifice) to the fuel tank on a continuous circuit. Race engine, donchaknow. You could, I suspect, pull the spark plug wires and run the starter for a while.

Chris

 

[Pebs]

hey speedy...it'll be fine. Just wanting to make sure the ignition is working properly, and if it is, it most definetly will fire. What I mean by fire is just that. I don't want it to "run" until it's done. I've ran chainsaws and all kinds of chit without any kinda muffler or pipe just to hear what it sounds like at WOT.

I don't have a starter. No battery, no elec. pumps, no power windows or on-star, just a good old fashioned dirty 2 stroke.

 

[BB454]

prime

If you have a compressor, remove the gas tank cap/gauge. Stick a blow nozzle in the tank with a rag around it. Apply small amounts of air. The tank will balloon a little when the pressure it applied. You should be able to see the fuel travel down the lines and into the carbs. May be a good idea to cut the pressure back on the air line if you have a regulator on the compressor.

It will run with out the pipe, noisey but it will run. No top end with out the pipe.

 

[rdr99]

Pull the plugs and pull it over about a dozen times. If you start it without the pipes on, it is going to make one heck of a mess of your bellypan.

 

[bart0678]

If you have a compressor, remove the gas tank cap/gauge. Stick a blow nozzle in the tank with a rag around it. Apply small amounts of air. The tank will balloon a little when the pressure it applied. You should be able to see the fuel travel down the lines and into the carbs. May be a good idea to cut the pressure back on the air line if you have a regulator on the compressor.

It will run with out the pipe, noisey but it will run. No top end with out the pipe.

This is how i prime all my carbs sleds after a rebuild. A couple quick shots of air will fill the float bowls in no time and it will fire right off.
adam

 

[Pebs]

fired right up on the second pull. i'm kickass