Johnson 150 V6 stalling around 2000 RPM

[MRB78]

-I have 2005 Johnson 150 V6 outboard that stalls around 2000 RPM while in gear in the water.

-It set up for about a year, then I ran it, it ran like crap.

-I changed the plugs (they looked wet), pumped out the old gas, put it new gas with sea foam added and ran it for about 2 hours in the water. Again ran like crap. It runs OK in the yard on rabbit ears I can manual throttle up to 5000-6000 RPM and put it in gear and get up to 4000 RPM. It the water and in gear it stalls around 1500 RPM.

-I sprayed some valvtech de-carb in the carbs while running, following all direction on the can. I ran it for about 2 more hours in the water and can get about 2000 RPM while in gear. Again in neutral I can get about 5000-6000 RPM on it or out of the water it will run up to about 4000 RPM on the rabbit ears. Only time it stalls is when I throttle up in gear in the water. All spark plugs are producing spark I checked them individually.

-Any ideas, I am trying to get it running with out taking the carbs completely apart and cleaning them. I know it will need this eventually but am hoping I can get it going without that.

I am very green when it comes to Outboard engines. Any help is appreciated.

 

[Lindyman]

Re: Johnson 150 V6 stalling around 2000 RPM

Not sure what this would be but wanted to chime in. Doesn't really sound like carbs to me. About 2,000 rpms is what the engine will allow while in SLOW mode correct? I'm wondering if this is a timing issue, or temp sensor issue? Also, I'd be careful putting your motor at those rpm's with just rabitt ears on. I think anything above 2,000 rpm's requires either being in the water or having a load put on the prop, otherwise engine damage can occur.

 

[MRB78]

Re: Johnson 150 V6 stalling around 2000 RPM

If I was in SLOW mode could I still throttle up manually in neutral to 5000 RPM while on the water? Or get 4000 RPM in gear on the rabbit ears? I will disconnect the leads to the sensor next time i run it to see if this works, from what I read that is how to bypass SLOW mode.

 

[Lindyman]

Re: Johnson 150 V6 stalling around 2000 RPM

Let us know what you find.

 

[MRB78]

Re: Johnson 150 V6 stalling around 2000 RPM

-Took the boat out again today, I cleaned the fule filter and disconnecting the temp sensors didn't seem to help (over ride slow mode). Sprayed some Power Tune directly into the carbs and followed directions on can. Maybe it helped a little. I got imediate response when i pushed what looks like a valve stem on a tire. I pushed it while running and at first just air with some moisture came out but then fuel (i think) came out and the boat immediatly picked up. The valve stem is just above and to the left of the fuel filter when in looking at the motor from in the boat. It also has a red piece on it that turns like a knob.

-After pushing this valve stem and turning it slightly I was immediatly getting 3500 RPM out of the motor and running about 30 MPH.

-Does anyone know what this "valve stem" does and what my problem could have been? 3500 shouldn't be my max RPM so i think something is still limiting me, one or two clogged carbs but i am getting much better response from my engine.

-Any more ideas?

 

[edjohn]

Re: Johnson 150 V6 stalling around 2000 RPM

did you ever find out the problem, my 2000 150 hp stalled the other day, and had to tow back to the mooring, will start then stall. the red lever you were referring to I believe is the device for fogging/winterizing I thought.

 

[doug2150]

Re: Johnson 150 V6 stalling around 2000 RPM

I believe the valve t bea shrader valve it is where fuel pressure is tested with a guage

 

[daselbee]

Re: Johnson 150 V6 stalling around 2000 RPM

Ok then...

There is no getting around it...you need to do the carbs. No spray, no short cuts. It sounds as if the high speed jets (or HS fuel flow circuit) are clogged in some or all the carbs. This is NOT SLOW mode.

And to REALLY do it right, you should clean the throttle bodies, detailing the small holes in the sdies of the bores where idle fuel is provided to the engine.

And....make absolutely sure you sync the carbs properly...all butterfiles must be completely closed at idle, and operate in complete synchronization as the throttle is moved. No compromises.

When you manually move the red lever on the primer solenoid, you are allowing extras fuel into the engine BEHIND the carbs nad enrichens what is a LEAN condition preventing revs and power.

Clean the carbs properly.
The schrader valve is for an OMC engine fogger can that screws to the schrader valve and fogs the motor for storage.

 

[edjohn]

Re: Johnson 150 V6 stalling around 2000 RPM

I found out what my problem was, water in the fuel, I have a 2000 Seaswirl Striper, I took the small circular cover off the deck after I had found water in the separator. Under that cover is the gas tank connections, there was water pooling on top of the tank, must have been leaking in around the guage connection.

 

[jhublein]

Re: Johnson 150 V6 stalling around 2000 RPM

When you manually move the red lever on the primer solenoid, you are allowing extras fuel into the engine BEHIND the carbs nad enrichens what is a LEAN condition preventing revs and power.

What is the normal operating position of this red lever ? Does it need to be flipped toward the back of the motor or the front ?

 

[71Windsor]

Re: Johnson 150 V6 stalling around 2000 RPM

first remember there is no such thing as a mechanic in a can using more and different aerosol products is not going to clean your carbs by spraying it though them you will have to take them apart and clean each passage way out. second the red lever in question it needs to be back over the solenoid. see the photo I attached

 

[G-Force]

The red valve is for fogging during storage and is also a manual choke in case the primer solenoid fails it normal position is 6 o'clock 12 o'clock will choke the motor