Idling issue. Still not solved. Getting frustrated. 1961 40hp Johnson RDSL-23

chead98

Petty Officer 3rd Class
Joined
Sep 11, 2009
Messages
82
Hi guys. I used the instruction posted for idling issues and it's just not working for me. Here's what I'm doing to get it started. This is an old very manual motor.

With the needle set as insturcted, I open the choke, turn it over a couple of time till it almost starts. Then close the choke and turn it over again. Now, in order for me to get it stated, I have to open it out almost full throttle, then when it starts, I slow it down to regular idling speed. I have to play with the idling needle in order to keep it running too. I never had to do this before. Sometimes it will start to spit and backfire, then cut out. I then try to set the needle up again, but no luck. Just frustrating, and I'm sure annoying for the neighbours. I just want this running normal again. Really, should the idling needle cause this many problems.

From the seated point, I know there's a equation for the setting but should it be close anyway. I try to start a turn and a half back, but it's just doesn't start from there, it needs more gas. I'm losing alot of gas just from fooling with this, (opening the choke, etc..) I'm killing my battery too. Re-charging it way too many times.

Could it be something else? Thanks, Chris
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: Idling issue. Still not solved. Getting frustrated. 1961 40hp Johnson RDSL-23

Keeping in mind that you have a engine that is going on 53 years of age.

How long have you owned this engine?... Did it ever run normally?... Has it been sitting for quite awhile since it last ran normally?

What are the compression readings of each cylinder?... With the spark plugs removed, does the spark jump a 1/4" gap with a strong blue lightning like flame, a real SNAP?

NOTE:
Opening the choke... means that the choke butterfly is horizontal and no extra fuel is being pulled into the engine.
Closing the choke... means that the choke butterfly is vertical, closing off the carburetor throat, forcing the engine to draw in more fuel.

If the compression is okay, and the spark appears to be okay, the usual causes you explain could be, just to name a few:

1 - A wobbling armature plate under the flywheel. This would result in having the points change their gap (normally .020) as the timing is advanced. (see below)
2 - Wrong spark plugs... should be either Champion J4C or J6C plugs, gaped at .030.
3 - Carburetor fouled, gummed, clogged. (If sitting a long time, clean and rebuild)
4 - Carburetor adjustable needle valves set wrong. (see below)
5 - Broken diaphragm in the fuel pump.

(Magneto Armature Plate)
(J. Reeves)

If the armature plate has a a loose fitting, wobbling motion (the plate that the points, coils etc are attached to), it is usually caused by a slightly worn support ring. This allows the point setting to change erratically as the armature plate turns.

The cure is to remove the armature plate so that the support which is attached to the powerhead with 4 screws is visible. Then, with a screwdriver and hammer, or some tool of your choosing, and looking straight down at the support ring, make a slight indentation at what would be called the 12, 3, 6, and 9 O'clock positions. Install the armature plate and check for a smooth turning wobble free movement.

You may need to do that procedure a few times to obtain the proper fit (not too tight, not too loose), but it's worth the effort.

Use a small amount of anti corrosive grease between the aluminum ring and the brass support plate and also on the brass bushing of the armature plate when all is well.

-----------------
Depending on which carburetor you have on that engine:
(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

--------------------------------------------------
(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.
 

chead98

Petty Officer 3rd Class
Joined
Sep 11, 2009
Messages
82
Re: Idling issue. Still not solved. Getting frustrated. 1961 40hp Johnson RDSL-23

Hi Joe. It was running great until the idling needle fell out. Since then, it never really worked well. Spark was checked and compression was also fine. Sorry for the choke confusion, I had it backwards. I will check the armature plate and fuel diaphragm. According to you, the sparkplugs are wrong. There's NGK plugs in mine.. and they were black and wet when I checked them today.
Just to Note: I can get it running but I have to put it full throttle in order to get it running. It idles pretty good then. (with the hood off) put the hood on and it seem to eventually stop. That could be due to my mixture ( too much oil) I since then, added more gas to even it out. I will change the plugs first. Easiest 1st. Thanks Joe, appreciate your help here.
 

chead98

Petty Officer 3rd Class
Joined
Sep 11, 2009
Messages
82
Re: Idling issue. Still not solved. Getting frustrated. 1961 40hp Johnson RDSL-23

Hi Joe. It was running great until the idling needle fell out. Since then, it never really worked well. Spark was checked and compression was also fine. Sorry for the choke confusion, I had it backwards. I will check the armature plate and fuel diaphragm. According to you, the sparkplugs are wrong. There's NGK plugs in mine.. and they were black and wet when I checked them today.
Just to Note: I can get it running but I have to put it full throttle in order to get it running. It idles pretty good then. (with the hood off) put the hood on and it seem to eventually stop. That could be due to my mixture ( too much oil) I since then, added more gas to even it out. I will change the plugs first. Easiest 1st. Thanks Joe, appreciate your help here.
 
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