Johnson 115 VRO shot again? Need advice

[BMarkey]

I feel like it's deja vu all over again.

I'm having the same problem with my year 2000 Johnson 115 I experienced a year ago. After I did my best to get all the water out of the fuel (annual occurrence after letting the boat sit for seven months), the motor runs fine for several minutes but then starts revving a bit faster and then sputters out. I can keep it running by squeezing the primer bulb a couple of times, but then the same thing happens again a minute or two later.

The bulb and fuel lines seem to be fine.

And, now the "No Oil" light and beep are on. I have oil in the gas tank, so I am not worried about running the motor.

The oil is in the tank because I replaced the OMS (VRO) pump with a used model last year and wanted to make sure the oil side of the pump was working. Everything seemed to be fine after the replacement, but I only used the bat a few times (the oil tank volume seemed to be slightly decreasing).

Today I noticed that when I squeeze the primer bulb, gas shoots out of the rectangular section of the VRO pump on the rear corner (see photo).

My guess is this is not supposed to happen and the integrity of the housing is compromised - as is in cracked and not keeping a vacuum?

I suppose that means I need another pump?

Would a repair kit fix this (probably not because I need the housing, right)? Or maybe new diaphragms could stop the leak? I do not see any obvious crack in the plastic.

Folks, do you agree with my diagnosis. If so, can you recommend a source for a new pump, or a fix?

Edited May 20, 2011 by BMarkey

[BMarkey]

I just went out to pull the pump and realized the photo above is not of the pump but of the fuel bracket above the pump. The part that is allowing gas to shoot out (when the primer bulb is pumped) is, according to the diagram linked below, No. 26, where it is attached to the top of the rectangular thingy (No. 15) near (but not at) the screw hole. http://www.crowleymarine.com/johnson-evinrude/parts/57624.cfm

Could this be causing the pump to fail to continue bringing up gas and oil? I see there is a gasket where the cover attached to the rectangular thingy on the fuel bracket. I thought that might be my problem, then noticed the cover (No. 26) is slightly cracked.

[seahorse]

On how many websites have you posted the same question and images?

There is an oring under the cover of that plus a needle valve and float. Use the service manual procedure for setting the float level after replacing the valve and cleaning out the fuel cavity.

[BMarkey]

Update: It turns out that I already had that entire fuel bracket, including that vapor separator tank (rectangular thingy). It came with a used OMS pump I bought a year ago from Dunk. So, I replaced the entire bracket, separator tank, etc. The leak is gone.

All went well and the engine started right up. It ran decently for 5 minutes, then the same old sputtering, running a bit faster ad dying out returned.

The solid alarm went off again (which on my engine has always indicated low oil) and the light stayed on solid.

So, I installed a portable fuel tank and ran new premixed fuel to eliminate any continuing water problems. Same thing. Runs fine, then sputters out of gas.

So, I then removed the MS pump and took apart the gas side. The parts look clean and in tact. The housing appears solid.

I am stumped.

I could buy a new OMS pump and probably solve my problem, but that would be an expensive ($350-plus) gamble.

[BMarkey]

I removed the OMS pump again tonight and took apart the gas side. Nothing seemed to be ripped, cracked or out of place. The O-rings seemed fine and the diaphragm looked good.

So, I am still puzzled.

[seahorse]

The O-rings seemed fine and the diaphragm looked good.

How did the other diaphragm look?

[BMarkey]

What other diaphragm?

[seahorse]

There is an air motor diaphragm and a fuel pump diaphragm, various flapper and check valves plus an oil piston pump and the alarm electronics. There are pressure tests that can be done plus flow tests, alarm tests, and priming tests, all in the service manual.

This may help and it has a great picture of the insides of the pump:

http://continuouswave.com/whaler/reference/VRO.html

[BMarkey]

I used that diagram. Thanks.

Update: I replaced the fuel bracket with one that came with the used OMS pump I bought last year. I disassembled and reassembled the fuel side of the OMS pump, finding nothing obviously broken. I let it sit for a couple of days, then reattached the pump to the engine. I made sure to pump the oil primer bulb to get a good flow down the hose.

I started the engine and after running rough for a minute or two, it ran fine. It did not stall after several minutes as it had been doing and the oil alarm did not sound. The engine was very smokey, but that's probably because there's oil in the tank and the oil pump is also apparently working. I let it run for 10 minutes or so without any issues.

What now? Water test, I guess. Fingers are crossed.

[seahorse]

possible air leak in the intake hose connection?