Honda GXH50 Fuel Pump Install

enigma3778 · #1 (**permalink**) 04-10-2009, 10:45 AM

I am new to the forum, I'm just trying get some help installing a fuel pump on the honda gcx50. Please help.

HoughMade · #2 (**permalink**) 04-10-2009, 12:00 PM

Well, what's the issue? Do you have a pump that came with the engine?

enigma3778 · #3 (**permalink**) 04-11-2009, 12:29 PM

Yes, the pump came with the engine. There are three sprockets coming out of the pump--in, out and a third. Where does the third go to? Does it go to the vent on the fuel tank or to some location on the engine?

Dan · #4 (**permalink**) 04-11-2009, 02:52 PM

Just wondering, I didn't know the GX could have a fuel pump. I dug threw the manual and couldn't find one.
http://www.honda-engines.com/Engines...s/37Z4C603.pdf

Just asking, I have only seen gravity fed.

ocscully · #5 (**permalink**) 04-11-2009, 04:17 PM

From the land of OZ

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"They seem to be shipped with engines that do not have tanks.

It is a pulse unit. The two barbs kind of in line with each other are for the fuel line. You can blow one way in and it comes out the other. Those go to the lower tank and to the engine.

Rather than vacuum, I think it works on crankcase pressure. When the piston comes down, the pressure in the crankcase blows through the rubber tube connecting it to the back of the air cleaner.

Haven't found any instructions, but I assume you put a tee in the short engine tube and run a line down to the hockey puck pump. So it either works on pressure or vacuum or both?

That way you don't have to have a carb with a pump built into it like the China knockoff does if the tank is below the carb.

You will notice there is a sentered bronze filter in the side of the puck. I think that is the vent for the pump diaphragm.

Neat idea for anyone using a rack mount and has the tank down beside the engine to cut the height."

Hope this helps,

ocscully

Dan · #6 (**permalink**) 04-11-2009, 04:58 PM

Dang Ocscully, how cool is that? Thanks.

Had wondered what the tube back to the air cleaner was.

jimraysr · #7 (**permalink**) 04-11-2009, 07:17 PM

I think that the crankcase breather is required by the EPA?

The breather tube connection in the air cleaner has a restriction in it, so crank case pressure on the down stroke pushes on the diaphragm in the hockey puck pump. Then the pressure bleeds out into the intake air stream and any oil / gas fumes from the crankcase are burned in the engine.

Anyway, that is my take on the fuel pump.

I would assume you could prime the pump and the fuel line by blowing / sucking ? on the hockey puck line that normally goes to the crankcase breather.

An other solution would be a an inline primer bulb line is part of weed wacker engines.

Jim