1994 Johnson 40HP fuel pump is missing

[harryrenegade]

I just ended up with this motor on a pontoon boat I bought. The motor runs and idles ok but under load won't do much of anything. I started looking at the problem and their is no fuel pump installed. When I bought the boat I was told the previous owner had removed the VRO2 system and the fuel/oil has to be premixed which coming from the dirtbike world is standard on most two strokes.

I started looking and there isn't a fuel pump anymore. In it's place is just an inline filter. I found a replacement pump on line but I also can't find the sense line coming from the crankcase to make the fuel pump operate.

Can anyone give me a clue where to look for the missing sense ( pulse ) line? It's not in the manual.

[jonesg]

http://epc.brp.com/Index.aspx?lang=E...9-26fd710434dd

Pull up the fuel pump diagram.
The hose comes off the bottom for the pulse limiter, once you see it you might find its still attached to the engine block..part #4 in the pic.

[wilde1j]

Are you sure there's no pump? I don't think it would run w/o. It may be running on the fuel side of the OMS pump, with the oil plugged and disconnected.

[harryrenegade]

Hello!

I'm sure there is no pump. I traced the fuel lines and there is an after market filter where the pump should be. You can also see where the pump used to be mounted. There is also a bolt that someone put that is not characteristic of the other OEM hardware in the center hole of the original pump mounting position. I believe that center is the pulse port that operates the fuel pump. The boats fuel tanks are mounted a few inches above the intake to the carbs so gravity probably made the fuel delivery possible with just a little bit of posityive head. I had my wife just start the motor and I could feel the positive/negitave pressure on on my finger which is what the pulse signal should be. The absense of the fuel pump also points to the reason the motor starves for fuel when I put a real demand on it.

I could be all wrong on this but thanks for the advice. I'm going to order the fuel pump and see what happens. I'll keep you posted.

Brian

[tx1961whaler]

Without pictures, all I can guess it the the PO capped off the oil lines with the bolt and it is running off of the fuel side of the original VRO pump. THe motor will not run for more than a few minutes without a fuel pump.

[harryrenegade]

OK So I replaced the fuel pump and all the problems went away. No more stalling, hard starting, etc. I think it's fixed.

Thanks for the posts.

Brian