Johnson J30ELDE butterfly setting

[mytiburon]

Does anyone know the proper way to set the butterfly for the carb? (its a 1996 30hp)

I'll start by mentioning the boat is new to me, a little 14 foot lund that i bought and rebuilt over winter. All new flooring, gauges, electrical,water pump rebuild etc etc etc.
Anyways, After it got it ready for a test start last week, put the leg into a barrel and tried to start.....

Test 1- Wouldn't start. Investigated and getting no fuel from priming solenoid,so i repaired, also installed and gapped new champion plugs, checked compression 125psi cyl 1 and 120psi cyl 2 and now the boat starts but wont run without priming more fuel.
Test 2- Rebuilt the carb installed new kit, found previous owner installed the gasket between the bowl backwards. Reset the bowl float etc.Boat now starts easily and runs smooth but only stays running at about 1200 RPM AND with the high idle lever UP,which also slightly opens the butterfly of course.When i close the high idle lever the engine stalls, like the butterfly is choking the engine of too much air.

So my question is, should a closed butterfly valve actually have a small gap so the engine can run? If so is their a proper way to gap it?

 

[racerone]

No----The throttle plate should be CLOSED at idle.-------The primer solenoid is NOT a pump.-----It is a valve that works when motor is CRANKING.

 

[mytiburon]

No----The throttle plate should be CLOSED at idle.-------The primer solenoid is NOT a pump.-----It is a valve that works when motor is CRANKING.

I get that the point of the primer solenoid is for start only,its just something i repaired because it was not working, again the issue is motor wont idle/run unless the butterfly valve is slightly open though. Any suggestions

 

[racerone]

Trouble shooting is required.----Start with a compression test.-----How did you test that the primer solenoid was not working ?----They are simple and very reliable.

 

[mytiburon]

Trouble shooting is required.----Start with a compression test.-----How did you test that the primer solenoid was not working ?----They are simple and very reliable.

Compression is 120 and 125 respectively.

I knew the primer solenoid wasn't working because it was getting 12VDC and didnt hear a "click" when my key was pushed in & because no fuel flowed from the barbs. (even when the bypass valve was turned)
I ohmed out the coil and got 5 ohms so i know the coil itself was ok and should have been working. When i pulled the cover off the solonoid I realized "the last guy" to work on it put the plunger in upside down which is why it never worked. So i flipped the plunger the correct way, installed a new diaphragm now it clicks and spits fuel out as it should when it receives power. So all good there.

Then visually it looked as though "the other guy" put a gasket between the carb bowl and float bowl backwards. I tore it down put in a new Johnson carb kit and i was correct he did have the gasket backwards. So it is all rebuilt now and reinstalled.

It just will not idle with the butterfly closed, acts like it has no air and is being chocked off.

 

[Vic.S]

It just will not idle with the butterfly closed, acts like it has no air and is being chocked off.

Have you adjusted the idle speed setting ( 775 to 825 rpm, in gear) as described in the manual?

 

[mytiburon]

Have you adjusted the idle speed setting ( 775 to 825 rpm, in gear) as described in the manual?

No I haven’t done that yet, I don’t think I can get the motor off of high idle long enough to even put the boat in gear without stalling. It literally dies instantly when I put the high idle lever down.

I also checked the timing indicator, it nicely lines up with the 2 marks as the butterfly starts to open,and the butterfly is complete horizontal/open when the throttle is in the wide open position and against the stop.

Btw, all the help and feedback is very much appreciated

 

[Mohawkmtrs]

Sounds like it is not getting FUEL rather than not getting air at idle.

Did you set (initially) the slow speed needle at 1 1/2 turns out from lightly seated?

 

[mytiburon]

Sounds like it is not getting FUEL rather than not getting air at idle.

Did you set (initially) the slow speed needle at 1 1/2 turns out from lightly seated?

I started at about 2 and worked my way in and out 1/4 turn at a time

 

[jimmbo]

Have you adjusted anything on any part of the Throttle Linkage?

 

[mytiburon]

Have you adjusted anything on any part of the Throttle Linkage?

I did today and it is running quite well. I adjusted the linkage so that the butterfly is ever so slightly open and it idles pretty good now. I may have to make some adjustments on the water but we shall see.
I set the air/idle screw at 1.5 turns, it honestly doesn’t seem to have much change to the idle wether it’s screwed in or out from the 1.5

 

[jimmbo]

As mention in Post #2... The Carb is supposed to be Fully/Completely CLOSED at idle. Retarding the timing is what controls the Idle speed. Idle mixture can not be calibrated properly if the carb is open, even the tiniest bit. Perhaps you were just trying to get it to idle with the Timing retarded more than it can run.

Are you sure it is running on Both Cylinders?

 

[oldboat1]

If adjustment to the idle mixture needle has no effect, the idle passage at the top of the carb is probably blocked. If you remove the plastic carb cover, spray carb cleaner down every opening and make sure the correct gasket is used (kit may have gaskets for multiple). I believe there is a mid-range orifice at the top, and a high speed jet at the bottom. They both will need to be squeaky clean.