Fuel Pump VRO Problem 94 Johnson 225hp

[CoastalPete]

Hi, hoping someone can help me with my Johnson 1994 Ocean Runner power problem. Just put the boat in slip after 1st installing new plugs, new fuel/water seperator, new inline fuel filter, decarbed engine and filled up tank 110gal. (had about 20 gal. from last season but was stablized). Put it in water and ran low rpm's no problem, then went for test run and no power over 1300rpm's? Took it to slip, runs fine in idle and will rev up past 5000 RPM's with no load, although after she runs for awhile I do hear something not right when doing so, like a real suttle miss fire (but no banging, knocking, smoke, etc.). The RPM's also will not stay consistent, it will rev up and down a bit on its own? I also hear some clicking on the side of the fuel pump. I am not getting any engine alarms, except when I first started it up this season the alarm stayed on steady until I shut it off then never heard it again.

Thought maybe gas problem so added more fuel enzymes (Startron) and checked fuel water seperator for water and there was none. Had marina mechanic hook up seperate tank to motor same problem, so its not gas in tank. They also confirmed spark on all 6 cylinders. I also checked enginer wires at night and found no arcs. Also, the water coming out of the engine felt warm but not hot where I should be overly concerned it has something to do with running too hot and the engine's saftey system (SLOW, which I think keeps the boat RPM's under 2200 or so).

Thinking maybe its the VRO fuel pump (hoping nothing to do with power head), need to confirm this, any easy way to check, what is the clicking sound an air leak? If so, should I rebuild, replace with VRO2 or new type OMS (I never had a problem with fuel or oil before this). PLEASE HELP point me in the right direction!

Thanks,
Pete

 

[dish]

Re: Fuel Pump VRO Problem 94 Johnson 225hp

Listen to oms pump by putting a srewdriver on the housing and your ear on the screwdriver.Should hear a click every 20 to 30 seconds.Constant clicking means fuel side of oms pump has bad diaphram or air leak in fuel system.

 

[Fl_Richard]

Re: Fuel Pump VRO Problem 94 Johnson 225hp

Constant clicking would also be adding lots of oil which would degrade performance.

Loss of power could be the shift interrupt switch on the throttle linkage. This will kill half of the engine to ease shifting. It could be stuck in the closed position from months of sitting in storage. It's on the starboard side near the shift cable connections. You can disconnect the switch. If the problem is the switch this should get it running properly.

The RPMS are too low for SLOW to activate..... Provided your temperature switch is OK. Its easy to test with a multi-meter.

 

[CoastalPete]

Re: Fuel Pump VRO Problem 94 Johnson 225hp

How do you test temp. sensors? If I had a bad ground would that make engine stall under load?

I listened again for clicking on the fuel pump and it now seams more normal clicking every 5-10 seconds. Checked compression and that seams ok. New plugs are now black. Marina mechanic says the fuel pulse limiter was bad as it was leaking gas so he changed it and the rpms went from 1300 to 2800. Someone told me to clean carb with CRC carb spray and now she wont go over 1000rpms without stalling...looks like I need to take all carbs off and clean.