the evil is back. had it running fine for the weekend 2 hours into the ride started feeling loss of power, then backfiring (crackling like popcorn in the muffler), puffing a bit of black smoke. then the same problem i've been having for years, can't start it, fuel pump starts vibrating really loudly. checked to see if gas is pumping, no dice. service manual says pump, but i've tried different pumps with the same results. so i've narrowed it down to the fuel cut relay. but can relays go intermittent, or do the just go? or possibly wiring?
any help,....helps.

thanks
tom

 

Convert it to a vaccumm fuel pump and never look back!

 

a couple of questions for you.
Firsty though, if the fuel pump is running (vibrating loudly) then its not the fuel pump relay, because the fuel pump is getting power to be able to vibrate.

Ok, now the questions.

What is the fuel level in the tank when this occurs? is it usually about the same level when it causes the problem? If so, then you may have a perforated fuel pickup tube. That a frequent problem in those machines if they have sat for years.

Try refilling the tank to full, and see if it runs ok again. If so, you have a pickup tube problem.

Have all the fuel lines been replaced on the machine? If not, you should do so.

 

how do i do the vaccumm conversion?

 

for replacing fuel lines, can i use standard hose from an parts store or do i have to order from honda?

 

It requires a new vacuum fuel pump, and tapping into the intake manifold to get a vacuum source.
I dont think the fuel pump is your problem.

 

tried filling the tank to the top, and your right worked fine. is the fuel pickup tube just off the side of the tank by the fuel filter? if so can i just buy a roll of fuel line from an auto parts store and cut it to length, or do i have to order them through honda? also do you know a good online parts store for these older hondas? most are not very helpful.
thanks again
tom

 

The fuel pumps are famous for dying all the time. $10 vacuum pump some fuel line and a threaded nipple. You can tap into the intake, the block where the crankcase vents, or the crankcase vent box! U can use fuel line from the auto parts store. I think the pick up line in the tank is metal. I think!

 

Well... unfortunately, it sounds as though you do have a bad pickup tube, and there is no repair for it.
Replacing the fuel tank is about your only option.
You havent mentioned if it will run in the reserve position. if it will you can just run it there, but you will have to watch your fuel level very closely so you dont run out of fuel out in the trail.

On doing the vacuum fuel pump, I wouldnt bother, as we have determined that the pump is not your problem.
And if you did do that, do NOT use crankcase vacuum to operate the fuel pump... you will cause crankshaft seals to leak. the crankcase must remain vented to the atmosphere.

Anyway, try it on reserve, if that fails... you are going to have to find a tank on ebay or something.... If thats not an option, I have one other idea that I will share later today... Im off to work... good luck.

 

Sorry for misunderstanding. I meant you can drill a new hole next to the crankcase vent tube and thread in a nipple to attach the vaccum line to the fuel pump! I didn't mean to use the actual crankcase vent to run the fuel pump! As stated you will have to get a new tank or run on res and keep an eye on the fuel level! It isthe best mod I have made to mine! If you run in the mud or cross creeks very often your pump will fail.