fuel pump

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

cuathetop

Active Member
Joined
Apr 20, 2015
Messages
34
Reaction score
0
Location
Mchenry Illinois
the other day i ended up on side of the road. Bikes been running superbly then bamm was like i ran out of gas. I suspected the fuel pump. Bike started and limped home but only with alittle coke applied to keep from dying. I took pump off and ran it with hoses disconnected and im getting suction and discharge. Im baffled. Made it around the block today with horrible power and some backfiring. then died again and wont restart. Does a fuel pump soley prime carbs and then vaccumm take over or does the fuel pump work the whole time bike is running?
 
The fuel pump runs the whole time. Question....was the switch on run....or reserve? Run....will run all the time...until the fuel gets low, then the low level light comes on, and the fuel pump kicks off. To get the fuel pump to come back on, you have to swap to reserve and then it will run until your bone dry.
 
It was on run and i had just topped off gas the night before.The fuel pump had been changing its clicking cycle i observed prior days befor this happened. Longer clicking time and faster. Im thinking its working because the bike will run but the p.s.i isnt sufficient. Is this common? loosing there pump psi but still working?
 
Well are the rubber grommets in place in the pump that allow it to build pressure and stop clicking?
 
Yes just removed fuel pump opened and all looks good ran it with hoses disconnected and im getting suction and pressure.
 
no checked that too.blew trough hoses to make sure no obstruction also.gonna pull plugs next make sure one isnt damaged
 
out of curiousity i went to drain all bowl to see perhaps if i had bad gas. 3 of the 4 carbs had fuel in bowls 1 didnt give me a drop and it was on the side with kickstand so it was leaning that way. Looks like i have a stuck float?
 
out of curiousity i went to drain all bowl to see perhaps if i had bad gas. 3 of the 4 carbs had fuel in bowls 1 didnt give me a drop and it was on the side with kickstand so it was leaning that way. Looks like i have a stuck float?

You can tap on the carb body with the handle of a screw driver and see if that will dislodge the float.
 
tried that. didnt work im wondering if a pilot jet is plugged was can compressed air be used to blow through those?
 
tried that. didnt work im wondering if a pilot jet is plugged was can compressed air be used to blow through those?

You have to remove the jet block to clean them properly. The orifice is tiny. I've had to use very small wire to clean them. One thing you can try is squirt some carb cleaner in the bowl vent while running. I do this whenever I shotgun my carbs. You might get lucky. New jets are on my to do list, but just partially for that reason.
 
Yep stuck float and sounds like at the very least you need a shotgun treatment, although if your floats stuck probably a carb teardown in your future, good luck i just did mine, it's a learning experience these carbs are not like any i'm used to but with time and patience it's doable, if you can afford it send them to Dannymax or Sean.
 
i read the link on the shotgun method and was going to try that i have never messed with carbs and was afraid i would be opening up a can of worms. This problem occured out of nowhere is that typical?
 
out of curiousity i went to drain all bowl to see perhaps if i had bad gas. 3 of the 4 carbs had fuel in bowls 1 didnt give me a drop and it was on the side with kickstand so it was leaning that way. Looks like i have a stuck float?

OR, a bunch of crud plugging the drain hole to that carb.
 
Thanks guys shes running at idle perfectly after i did what you said. I know i will eventtually need to take carbs off at do a thorough clean but a project like that will take me some time and i want to ride. I dumped about a half can of seafoam into take so hopefully that will help too. I appreciate all your help expecially yours traumahawk
 
Thanks guys shes running at idle perfectly after i did what you said. I know i will eventtually need to take carbs off at do a thorough clean but a project like that will take me some time and i want to ride. I dumped about a half can of seafoam into take so hopefully that will help too. I appreciate all your help expecially yours traumahawk

Your very welcome. Glad the it helped.
 
Turned out i had a hole in backside of carb float bowl cover. replaced cover cleaned all jets in all 4 cabs while i had it off.
 
Back
Top