Hello new to the forum but did search for an answer. 2nd Fuel pump replace in 6 years (filter hoses and Pump) also took the injectors and had them cleaned for the first time. Problem the bike will not start, runs only as long as I spray starting fluid thru the air intake. tested the injectors but do not see any fuel coming out. when I turn the key to on I her the pump for 2 seconds, and when I try to start If I put my ear to the gas tank I could hear it engaging. Could I take the hose that comes out of the tank the high pressure one to see if gas comes out when I crank to see if is working, I do not have a pressure tester or the bike ill not start to test the pressure. I just want to test as much as possible before continuing to the pressure regulator in which I have to spit the bike apart to get to it.
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850R Fuel Pump Test
- Thread starter arturo007
- Start date
gsaddict
Pepperfool
You don't need a pressure tester
The lower hose to the fuel spider/regulator is the pressure line from the pump
The upper hose is the return
Pinch off the upper line coming from the tank and block the line from draining.
Remove the line from the spider
Attach a short length of 5/16" id hose to the spider and direct into a suitable container
Turn on the ignition and let the pump cycle
Do this 3 times
Does fuel come out each time?
Report back
The lower hose to the fuel spider/regulator is the pressure line from the pump
The upper hose is the return
Pinch off the upper line coming from the tank and block the line from draining.
Remove the line from the spider
Attach a short length of 5/16" id hose to the spider and direct into a suitable container
Turn on the ignition and let the pump cycle
Do this 3 times
Does fuel come out each time?
Report back
Thanks, I will try tonight when I get home. That is what I wanted to find out. So I will take out the bottom hose and gas should come out when Im Cranking? Try 3 times if it comes out the pump is working. But if it does not I will double check the lines maybe I crossed them by mistake. Like I said I wanted to eliminate everything before I went to the Pressure regulator.
Thanks, Art
Thanks, Art
Hello I was able to test the gas pump, but no gas came out, I was able to drain a lot of the gas using the return gas line, and siphon the rest, tonight I will take the pump off again to see what I did wrong... I'm wondering if the mark that I made on the plate was not the correct one and maybe I had it facing to high and was out of the gas line? Does anyone have a picture of the plate? the way it lines up with the gas tank?
Thanks in Advance, Art
Well the latest, I took the plate of the tank took the pump out and tested it and it works, I check for continuity from the plug to the inside and they are working. The cables in the inside are pretty brittle and I have a couple of cracks on the cable that you could see the braid, could that be it? but I see everything is expose and submerged so maybe not (Magic) I guess, also when I touch both poles on the pump wile connected it showed continuity also, is it supposed to do that?
SOLVED!!! THe new pump has REVERSED Polarity on the connections.
After tediously replacing all the wires in the plate, they were all brittle and about to fall of, I put it back together and same thing I could hear the pump but nothing will come out (I new the pump was working I tested it outside) so I decided to do one more test, I jumped the cable coming out of the tank directly to battery and it ran but nothing came out so I switch the cables and Viola!! it work.
DO NOT DO THIS... so to save time not to take the dammed pump out again I cut the wire on the outside and reversed the wires, It started for 40 seconds and died, fuze burned, put another fuze burned it again. So Guess what, I fixed the wires back and took the pump out, change the cables for Polarity, the (+) is the smaller stud and the Negative is the bigger one.
Put it all back together, and started even without the choke on after a year of being shut down, guess having the injectors cleaned also helped.
Hope this helps someone in the future
After tediously replacing all the wires in the plate, they were all brittle and about to fall of, I put it back together and same thing I could hear the pump but nothing will come out (I new the pump was working I tested it outside) so I decided to do one more test, I jumped the cable coming out of the tank directly to battery and it ran but nothing came out so I switch the cables and Viola!! it work.
DO NOT DO THIS... so to save time not to take the dammed pump out again I cut the wire on the outside and reversed the wires, It started for 40 seconds and died, fuze burned, put another fuze burned it again. So Guess what, I fixed the wires back and took the pump out, change the cables for Polarity, the (+) is the smaller stud and the Negative is the bigger one.
Put it all back together, and started even without the choke on after a year of being shut down, guess having the injectors cleaned also helped.
Hope this helps someone in the future
pglaves
#13338
Indeed, when the pump runs backwards it doesn't squirt out much fuel.
I did bang my head a couple of times... they should have put a notice along with the pump about the reversed polarity. That's all I have to say.
pglaves
#13338
On several occasions I have encountered "stuck" fuel pumps. Out of the bike and on the bench in a pan of kerosene I have been able to free the pump by reversing the polarity to make it run backwards.
Last edited:
gsaddict
Pepperfool
With the pump removed
Hitting it with 24v for a couple of seconds works too! Jog back and forth.
