1993 Johnson 140HP V4 Engine Help

[MatLat]

Me and some friends are trying to wrench on this motor and understand the mechanics behind it. Our first action was siphoning all the old fuel out as it sat for 2 years and replaced it with new fuel.
The first time we took our boat out we were cruising wide open for 10 minutes before the engine started "bogging", ( never fully died), seemed to only do it a high rpm. Happened for the next 30 min all the way to the dock.
We replaced the fuel line and primer bulb. Took it out after that and it ran like a champ for the next hour, no problem at all. On the way home we fired it up, threw the throttle down and it fully died, fell on its face after 5 min. Wouldn't turn over after than.
We were left stranded and called for a tow. While waiting for a tow we finally got it to fire up after about 40 min, and putted back to the marina.

People are telling me its the fuel pump, others say it may be a spark issue. That specific engine is a 2 cycle with a VRO fuel pump.
Any advice on this issue would be greatly appreciated.

Thanks,
Matt

 

[AEROCOOK]

First of all, you took a huge risk in just siphoning out the old gas and hoping for the best, hopefully you haven't done any damage.
A "new to you" motor that hasn't run in a few years needs some attention prior to being put back in service, things like a new water pump impeller, carb cleaning etc. Go to the stickys and read up on "Awakening a sleeping outboard" this will get you going in the right direction.
Also, if the VRO is still hooked up, it would be a good idea to run premix gas for the first few tanks while monitoring the oil level in the VRO tank. This will tell you whether the VRO system is delivering oil.

 

[MatLat]

I got this boat from my grandfather and uncle. It hasnt hit the water in 2 years since i got it 2 months ago. But my uncle started it up a handfull of time in the 2 years. He explained to me that the impeller was replaced and had only 10 hours on it. We checked the sparks on it after recieving it aslo.

Im going to rebuild and clean the carbs. See what happens.

 

[James R]

Everything that AEROCOOK said is essential to getting this motor back on line, including the impeller. You don't know the condition of the impeller. Replace it anyway. No sense in risking a good motor for the sake of a few bucks. Change the lower unit oil and replace the plug seals when you do. I have never trusted the VRO system to deliver oil. I disconnect the oil line, plug the oil input to the VRO, disconnect the electrical connector from the VRO and run on 50:1 Mix. The fuel pump part of the VRO is quite reliable. Always use Stabil Marine in all of your Gas and fit a water trap filter in your fuel feed line. Many reasons for all of this and all of them good. By the way if you don't fit a water trap filter you could block the carbs again because there is sure to be crap left in the tank.

 

[rjcamel2355]

Carb rebuild would be a start. I personally wouldn't trust an impeller that has sat for 2 years. If it's throwing a good stream, great keep running it, just keep an eye on it. (even though it has been started a handful of times). Clean the carbs, check the spark, change the plugs. Likely if it was running good and went to **** on you like that it's something fuel related/something stuck in the carbs. Run a compression on it, just to be safe and post your results.