Vro conversion problem

[surfguitar7]

I have a 1992 johnson 40 hp that I just converted from vro to non vro by using a fuel pump and doing away with the old vro system. I am unable to get the primer bulb to stay hard and gas is coming out through the foot of the motor. I bought a sierra pump with lines and attatched it directly to the manifold. I blocked the old pulse line. Would gas be able to go through the pulse line or is possible that my carbs floats are not seated properly? I am going crazy trying to figure this out. I just rebuilt the carbs and changed everything out and I am not sure if the floats are set properly. Any help would be great. I have checked the lines and nothing seems to be leaking but a lot of gas is coming out.

 

[seahorse5]

Re: Vro conversion problem

just remove the pump leaving the hoses attached, then squeeze the primer ball. If you see fuel come out of the pump pulse fitting, then you know its bad.

 

[surfguitar7]

Re: Vro conversion problem

This might sound really stupid but I was under the impression that once I removed the screw capping off the pulse line the new pump would butt up against the open void, thus becomming the new pulse line. Is that correct or was I suppose to thread the new pump with a pulse nipple that goes into that center screw area on the side? If the pump is not leaking then would the carbs be the problem? Thank you.

 

[surfguitar7]

Vro conversion problem

I think I need to re adjust my floats. It is the only place I can locate gas coming out.

 

[DargelJohn]

Re: Vro conversion problem

Did the motor run before you replaced the VRO unit with the Sierra fuel pump?

Normal procedure to convert from VRO to a Premix setup is to: 1) Disconnect the electrical pigtail on the bottom of the VRO, 2) Cap off the the oil supply line, 3) Be sure to purge the system with premixed fuel before starting.

No need for a new fuel pump, the fuel pump side of the VRO will continue to function as normal.

Holding a Carb upside down, the float level should be set to where the float middle seam is level (parallel) with the carb body mating surface.

Good Luck

 

[James R]

Re: Vro conversion problem

I can't see from the parts drawings that you have the coupling point for the standard type pump. ie the two required tapped holes one each side of a pulse hole. The pulse hole usually has a plug in it when using a VRO pump. I am assuming that this is the case. I assume the pump is new therefore there should be no pump problem. If all this is true then your problem is indeed a carb problem. Sounds like one or more of the carb float valves is not sealing off. Further confirmed by the fact that the bulb will not harden. Check and reset the floats. If you are running with old seats and needles then you are asking for trouble.

 

[surfguitar7]

Re: Vro conversion problem

Sorry it has taken so long to get back on but here is the update. I bought the motor used and it had the vro capped off. I knew the motor had sat for a while so I decided to go ahead and put in the non vro pump. I also rebuilt both carbs and installed new everything. I went out and took it back apart today to see how the floats were holding up and everything measured correctly and it sealed when I flipped them upside down to blow air in. I am still having the same problem. I blocked off the old pulse line and the only thing I can think of now is either my primer solenoid (which I just replaced but it could be a bad solenoid) or bad needle and seats. I even switched around the gas feeds thinking I might have hooked them up wrong on the carbs but I get the same result. I pump the primer bulb and it doesnt get hard and gas leaks from the foot of the motor. I was able to start the motor and it would run and die before I re did the carbs and took out the vro pump. I really appreciate the help, thank you.

 

[retiredfornow]

Re: Vro conversion problem

Go to boats dot net, parts, johnson, 1992, and find your motor number and look at the fuel pump.
Does your new pump look like the one there?
Maybe you have the wrong one, or....?
I tried to put in a link for you, but can't get it to work.

 

[rtek816]

Re: Vro conversion problem

Pull the pulse line and pump the bulb. Fuel coming out?

 

[surfguitar7]

Re: Vro conversion problem

I think I found the culprit. I had a pinhole size hole in one of the gas lines. I replaced and it seems to have improved. I will try to crank her in the morning and hope for the best. Thanks again for all the replies. I bought the Sierra pump that does not have the pulse line. I unscrewed the one bolt plugging the pulse and bolted the new one right up. I work in the fishing and parts dept at West Marine and according to our catalogs I got the right fuel pump. I will get the numbers and post to be sure.