HIGH Idle Not Going Down- 96 Johnson 130 V4

I have a 96 Johnson 130hp V4 looper and my motor runs at a very high idle at 1200 and lately surges to 1900 rpm's and can sit there for some time, then drop back down to the 1200's before going back up to the 1800 to 2000 range.
It's driving me crazy trying to track down the reason for the really high idle, so I'm hoping someone here could add some insight to a fix.


First off I am running my motor off of a 1 gallon gas can with the hose stuck in through the cap opening that is just a little larger than the hose. The reason for this is I just purchased the boat and the previous owner had mention he was doing premix in the tank along with using the VRO. So currently I'm in the process of taking the old gas out and cleaning the tank. I also disconnected the VRO so I can control the amount of premix being used.

My first questions is, could using the gallon can create the motor to run at a really high RPM by sucking in to much air? I've done this exact setup with my 2 stoke Yamaha and never had this high rpm issue, but this Johnson is a different monster.

2nd, I've checked for vacuum leaks and didn't see any, I have replaced my coils, plugs, and plug wires. I looked into the carbs and I can see the butterfly valve in all carbs have the same very small gap, not completely closed, but there is a 1/16" or less gap. I wouldn't think this small of a gap could cause the idle to take off to 2000 rpms could it? See picture below.....

3rd, I've back out the idle screw on the motor when it's at this high RPM and it does nothing, the engine continues to run high.

All suggestions are more then welcome ! Thanks all in advance...


Here you can see how much the butterfly valve is open...

Check to make sure roller is not touching throttle cam...and if the screw you stated you adjusted is the one at 11 o'clock that a mid range air adjustment put it back at about 1 -1/4 turn outs

Are you doing these test on a set of hose muffs or with the lower unit submerged in a tank? Hose muffs would explain why your idle is high but I don't think that will explain the varying RPM. Something is going lean for the RPM to climb like that.

Like a case leak or timing

Magnet shift, woodruf key for flywheel?

I went ahead and rebuilt the carbs and primer solenoid and had a really hard time starting it up. Fuel doesn’t seem like it’s the issue, but I tested the stator on Ohms and got 400 and 75-80 on cranking volts, so it seems the stator has issues.
When it did start it did run better, but at 1000 rpm on muffs without the sneeze, so it seems I’m heading in the right direction, I hope.
I’m thinking of pulling the flywheel off this weekend and possibly ordering a stator and going from there. If it’s the flywheel I guess I’ll be buying that as well, we’ll see.

The throttle butterflies being open to any clearance IS NOT a idle setting. the throttle roller is obviously touching the cam for the butterflies to be off idle.

Back the roller away from the cam so it is not touching anything. Now, make sure that all of the butterflies are in synchronization so that they open and close at the same time, then adjust the roller so that the throttle butterflies just start to open when the roller is dead center with the cam's scribe mark.

According to an available database here, that rpm fluctuation is most likely due to the butterflies not being synchronized.

1000 RPM on a hose is about right...Sync and link on engine needs to be in barrel or lake.

That’s good to know about the 1000 rpm on muffs.
Im now chasing a ignition problem which I believe after testing I’ve got narrow down to the stator which I should be able to put the new one on tomorrow or this weekend.

After getting the flywheel nut off, the flywheel is really stuck on and the puller is not working that great.
I was thinking of spraying some WD40 or “Freeze Off” on it and letting it soak, good or bad idea????