'87 vfr700 fuel pump help PLEASE

my fuel pump on my bike has stopped working constantly. it broke down on me 6 times today and i had to tap it and blow on the top where the contants make a spark. anyway the thing is on its last leg so i was wondering if anyone out there knows where i can get a replacement? its though to fine parts for my bike and last time i posted something for a speedo drive some had on here but i already bought one on ebay.

So i'm asking for some help if anyone knows where i can purchase a good fuel pump for a 1987 vfr700? the pump on there now is a mitsubishi pump so i assume that a ton of vehices used this type of pump. can anyone point me in the right direction?

 

you can use a low pressure fuel pump, I just put one on a FZR
I got the link from tinkerinwithstuff, it was only 35 bucks or you can get the same at auto zone for around 75.
If you can't find one, I think I still have the guys # he is in CT and will ship. You have to do a bit of mod to fit it somewhere but it is a low cost fix.

 

yep thats the one... top link he has prob 20 diff types.
Thanks tink

 

The same exact pump was used on a wide variety of bikes, so chances are good that you could get one from a salvage yard.

 

You should try running it with gravity feed (no pump) first. That same pump failed all the time with the 1st gen CBR1000F Hurricanes, consequently Honda dropped them and when to gravity feed for the 2nd Gen. I pulled mine off my project '88 Hurricane and it ran fine so you should have no problem gravity feeding a 750.

 

I didn't know the VFR750 was sensitive in that way, I will tell you that I ran an inline filter while I was gravity feeding. He should still try it, he has nothing to loose.

 

Hi Tink, could you please clarify - are you saying that below half a tank on a VF500F you can get insufficient supply?

Thx!

 

5x5 on the VF500F. Thx!

 

I'd rather do it the way it was meant with a fuel pump. i picked one up at advanced auto parts today...it was a 2-3.5 psi but I'm a little confused with the wiring? it has a red one and a black one. the black says NOT to hook up to positive and its a ground. my old pump had two wires too but they were both hooked up to the two line available.

 

what was the fuel pump you picked up...I am having intermittent problems with mine as well...........I get on the freeway.. get up to speed about five miles down the road she starts to sputter..so I pull in the clutch lever, throw the choke all the way on, and hit the starter button.. it takes a few seconds but she fires right back up let go of the clutch, turn the choke "off" give her some gas and off we go.... it quit for a while after I laid it down but it started back up sound familiar? it only does it on the freeway...never surface streets........ and my fuel filter is usually only 1/4 of the way full...shoudln't it be full all the time? sorry about the highjack...

 

i got the cheap stuff called mr. gasket. it was a 2-3.5 psi and 20 something gallons an hour. i'll see if it works tomorrow

 

I run my Honda VF1000R chopper all the time without a fuel pump. Not a problem.
Why pressurize a system if not needed, It just makes a fire hazard. One little leak and it will spray fuel everywhere.

Many big triumphs,Harleys,and BSA.s do not use fuel pumps and have won many races .
They just put fuel pumps on to get ready for fuel injection. If you have fuel injection then you need a fuel pump. Pressure has to be right for injectors to work. Not carbs though.

 

If you really want to break it down, the formula is as follows:

Head (in ft) x the Specific Gravity of the fuel, divided by 2.31

Gasoline is typically around 0.72 for the specific gravity, so let's say the tank is 1 foot tall....thus (1x0.72)/2.31 = 0.312 psi. at the petcock. This calculation also implies that the tank is full all of the time.....this calculation is also based upon a one inch diameter column of liquid.....

using a standardized wag that a refrigerator is 6 feet tall and the hose coming off the tank was 1" in diameter, with a full, one foot tall fuel tank, you would still only see 2 psi at the end of the hose. That is "dead head" pressure...if the hose is open and the fuel is flowing, the pressure would then be "Dynamic Pressure", thus, the pressure at the end of the hose would be even less.


Just some food for thought.

 

There are some assumptions being made with this statement.

 

besides that Donald, your tank is not a stock honda tank is it? if it isn't then gravity feed will work just fine... the internal "pipes" of the tank ( the feed pick up going over to the petcock then back down to the bottom of the tank) look like a roller coaster on the inside...therfore, if you gravity feed the tank , it will only go down as far as the tubes first bend. Which is about half a tank ,roughly.... As much as I like Honda products, I really don't think that they had the crystal ball working and were planning to go fuel injected in the future decades..(like tinker said).. if the petcock was external like these: it would totally work.