aftermarket fuel pump

[tvmax]

Is it possible to run a low pressure inline pump? 2 to 3 lbs psi. It runs continuously not cutting off like the stock one. Anyone tried this?

 

[one2dmax]

That is what most aftermarket and ebay pumps do. That isn't ideal but can work. Tends to create a "dead head" situation where the fuel heats up in the pump since it doesn't flow and cool it down.

 

[Ron Mabey]

I had a1992 VMAX with a low pressure fuel pump. The clear fuel line from the fuel pump to the carbs sprang a leak. When I went to replace the fuel line I noticed that it had sprung the leak at a point where it was crimped. I installed the new fuel line with care not to crimp it. With the new fuel line in place the low pressure fuel pump didn't have enough power to get fuel to the carbs; the crimp in the fuel line was necessary to get fuel flow. The crimp created a venturi effect that overcame the low pressure of the fuel pump. With a new fuel line in place (crimped) the bike ran fine. Realizing that the crimped fuel line would fail with time, every Spring thereafter, I replace the old crimped fuel line with a new crimped fuel line and had no further fuel pump or fuel line problems.

 

[wayne billings]

Hi I recently installed a ebay inline pump( carbone brand). I have not been on the road yet. max psi is 7 lbs.. So far so good. It should be on the road in 2 weeks and then I can post more.I do intend to go with a stock pump simply because of the unknown reliability of the carbone pump. via con dios

 

[Fire-medic]

When I went to replace the fuel line I noticed that it had sprung the leak at a point where it was crimped.

By that I assume you mean the bend was excessive, and the interior diameter of the hose became a narrow-oval at the bend, instead of an undistorted 'O' as it should be, for maximum flow.

That excessive bend causes the hose to distort, and to create stress-points where it bends more-than it's designed to. Over time, the stress-points coupled with the engine vibration, heat cycles, and other dynamic factors, one of which could be excessive fuel pump pressure, causes premature failure. Replacing the hose annually is not the best solution, because if the hose develops a failure during that riding season, you could end up with the fuel pump hosing-down your hot engine & exhausts with copious amounts of flammable liquid. Do you wear Nomex underwear?

I suggest using a routing which eliminates the stress-points, returning to the OEM hose (molded rubber gas hoses like the T-hose feeding the carburetors can last decades, and aren't expensive, buy them while they're still available) or using some other hose which prevents the inner-diameter distortion of-which you speak (ever seen the nylon thread-reinforced clear gas line?) or some other way to eliminate the problem.

I've used 1/4", 5/16", or 3/8" steel brake hose, cut & bent on a tube-bender, to make connections on cars and trucks for gasoline delivery. I suggest using fuel-injection clamps instead of perforated hose clamps such as you'd use on a water hose from the engine block to the radiator. They don't have sharp-edged slots which over time, cut-into the hose rubber.



I think 7-8 PSI is too much pressure for a bike like ours, a max of half of that value would be much-better suited to be controlled by the carburetor float needle & seat. Again, the last thing you need is gasoline spraying all-over the bike and the rider/passenger.

 

[3-Max]

OEM fuel pump is 3-4 psi. I recently fitted a cheap ebay OEM type pump which looks to be working fine. Have a look at this thread.
https://www.vmaxforum.net/threads/replacement-fuel-pump-bracket-swap-pt1.51865/

 

[gentsvmax]

Iv been running this one from Mr Gasket for a couple years now, about 27 bucks