Bog/Stall/Die on Throttle

[vorsprung]

I have a 2000 Johnson J150PLSSC that bogs/stalls/dies at holeshot, I pretty much have to feather it past 2000 rpm and then it runs like a banshee at WOT. I've noticed a pattern though with this issue, it happens after the engine is fully warmed up, not when it's cool. It still doesn't idle the greatest but it does start everytime, the low speed needle valves were all varying turns (4-10), I've now set them all to 5 turns.

So far:
- Rebuilt Carbs with OEM parts (verified float height)
- Replaced Vapor Separator Gasket/Needle/Seat/Float (verified float height)
- New Primer Assembly
- New Champion Spark Plugs, CDI Wires and Coils
- New CDI Optical Sensor
- Mechanic inspected Impeller (pees just fine) and compression test checked out
- Rebuilt VRO with new OEM pump motor/diaphragms/oil bulb/oil tank filter
- Verified no ASV valve off the tank and checked for any cracks in the pickup tube, replaced all fuel lines, bulb, and fuel filter.
- Took off both Throttle Bodies, cleaned and put in new gaskets
- Verified rectifier is working at specification.

The only thing I found new today was that the stator has higher than specification resistance (0.60). Spec is 0.05-0.19, could this be a possible root cause of my problems before I drop $400 CDN on a new stator?

 

[brodmann]

You mentioned both Carbs and throttle bodies. That's a bit confusing to me.

 

[vorsprung]

Yeah, I rebuilt the carbs and then pulled the throttle bodies off, cleaned them out and replaced both gaskets. Then re-attached the carbs onto the throttle bodies. #1 is a throttle body, carbs you can see, gasket is #64.

 

[racerone]

Why all the new parts ?----Checked carburetor bowls -----They are often warped.

 

[Faztbullet]

After you feather it to get it going, will it take off if you stop for a minuite?

 

[vorsprung]

After you feather it to get it going, will it take off if you stop for a minuite?

Nope, have to feather it again or it dies.

 

[racerone]

Check float bowls.

 

[vorsprung]

Why all the new parts ?----Checked carburetor bowls -----They are often warped.

-Carbs were just a place to start, I did check with a flashlight and a ruler to make sure the bowls were not bowed. I replaced the throttle body gaskets because I took everything pretty much off the engine this past winter, they were pretty smashed down so I put in new ones to prevent any possible future leaks. I did clean out the throttle bodies really good to make sure there wasn't any blockages.
-Previous owner put in the wrong spark plugs
-Spark plug wires looked like they were the originals from 23 years ago
-2/3 Coil Packs were way out of spec for resistance
-Fuel Bulb/Line looked like the original from 23 years ago, fuel line was the original so to rule out any breakdown inside the hose and any air leaks I replaced it.
-Oil Bulb looked like the original and was fairly rigid, didn't know when the last time the tank filter was changed last.
-VRO pump motor was leaking oil at the intermediate seal and had knock-off brand diaphragms (they were a little ratty looking also). I did vacuum check the entire fuel bracket component system to make sure there was no leaks when I reassembled.
-Fuel filter was fairly yellow/old and was plugged up
-Vapor Separator Gasket was fairly smashed and was leaking. Needle was rusted and sticking in the seat.
-Primer rebuild kit was done based on a suggestion from another forum site to correct a starting issue. The filter in the primer was also fairly yellow and did have grit in it.

 

[brodmann]

When cleaning the carbs, did you run a piece of wire or a jet tool through all the jets? Did you set the float levels like they are supposed to be? Was the motor working properly before you took it all apart, or what was the reason for all this work to be done?

 

[vorsprung]

When cleaning the carbs, did you run a piece of wire or a jet tool through all the jets? Did you set the float levels like they are supposed to be? Was the motor working properly before you took it all apart, or what was the reason for all this work to be done?

Yup, used a jet cleaning tool to make sure there was nothing gummed up.

Carb floats were all checked to make sure they were level (both directions).

The motor wasn't working the greatest when I got it. Idled terribly and sometimes it would take a few times to start it. I also wanted to make sure this engine was primed for the boating season, unfortunately that hasn't exactly panned out.