Fuel Pump

[redgambler]

Been having some trouble with my 2006 vmax. Well started trying to figure if the carbs need going through which would have been a suprise considering that after the shotgun and sync. it was running better than ever. I found that I was getting no fuel to the back left carb because I couldn't get any fuel out of the bowl drain. Well I checked the filter and it was clear and the I took the fuel line off of the carb side of the fuel pump and cycled the key and got no fuel out from the fuel pump. I could get fuel through with a little air pressure on the tank through the fill nozzle, cycle the key no fuel. Well that tells me fuel pump is bad, unless that pump does that. 200 dollars for a new one. Any one retro fit a cheaper electric pump on their bike with success? Any advice would be appreciated need to get this thing going, need to ride.

 

[alorio1]

Have you checked the tank vent line? does the fuel pump run ?

 

[redgambler]

Yes the pump runs, it seem to have a vacuum seal but while i did these these, (cycleing the key on and off) the gas cap was off of the fill neck wide open to the atmosphere.

 

[alorio1]

Your fuel filter doesn't have to be blackened out or look stopped up to be plugged, but if you can blow thru it with ease its probably ok. Here is a good read on how to check your internals on the fuel pump, a lot of members has found this when their fuel pump quit pumping, including me...

http://www.vmaxforum.net/showthread.php?t=8775

 

[redgambler]

Thanks Alario1 I tried to find some info on the search first, but I didn't get anything I could use.

 

[one2dmax]

Also make sure there are no pin holes in the hose prior to the pump. It will only suck air if so. You can take the pump off, hook a new hose to it, set the hose end in fuel, and hotwire the pump on. See if it sucks/pushes fuel at that point. Also, it's common for them to displace one or both diaphragms which can make it not work. It's not often the pumps completely give out (but it does happen).

Sean

 

[redgambler]

Man I appreciate all the help. Bike running better than ever. Both rubbers for the check valve part of the fuel pump were laying loose. Put them back in and pushed the tit into the hole and it ran awsome on the kick stand, went to take it out started running out of fuel after take it back appart saw one of the rubber seat wasn't quite seated, my eyes ain't what the use to be. Went back on a ride and got more power than I can remember ever haveing since I got the bike. Thanks for the help again. One more thing I wonder how I was even running before. Is there a certain amout of vacumm draw on the fuel system?

 

[alorio1]

Nope, no vacumm source, no gravity feed since the tank is mounted lower than the carbs........

 

[redgambler]

Well don't know how it was getting the little gas that is was getting, and thanks again.

 

[jfeagins]

Those two little rubber diaphrams can be a PITA. If one of them falls loose, the pump seems to be able to keep up, albiet, will cycle almost constantly to do it, but if both come loose at the same time......

I've had to go through the pump on my 85 three times over the years. Don't know why they come out sometimes, but not necessarily constantly.

 

[redgambler]

Yea I believe the power difference that I have been running on a faulty pump for a while.