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1961 40Hp Evinrude Idle

dr_strangelove

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"Hi all...Just purchased a &#3

"Hi all...Just purchased a '61 Evinrude 40HP on a 14' Aerocraft as a boat for my cabin. The motor stars and runs fine, but does not want to hold a low idle. For instance...Tonight I took it for its "sea trial" and ran wide open without a problem. The problem was around the dock when wanting to go from fwd to rev. When I "chopped" the throttle, to allow me to engage the rev, it just died. Will only hold idle just below the "start" indication on the motor, no lower.

Also, there is a trangular knob above the butterfly on the carb...It turns, and I assume it is used to adjust something, but what? All of the writing is gone. Am I correct is running 24:1 in this motor? Thanks in advance."
 
"I do believe that the "kn

"I do believe that the "knob" you are talking about is the "low speed idle adjustment". If it is it directly controls the "low speed jet" (mixture of air/gas). The one on my Ev is quite snarky some times and can not constantly be left in the same position. Literally, depending on the weather/humidity etc, it has to be re-adjusted to produce a satisfactory idle. I would suggest starting your motor, give it enough throttle to keep in running - reduce your rpms until it starts to chug then try the adjustment first clockwise, then counter. It takes a second for it to respond so don't get impatient. Keep fiddling with it until you can back the throttle off completely and it is idling smooth. If you can't get to that point, I would first try changing the needle valve (on the end of that knob) and if no luck with that, the carb may need a total rebuild."
 
Sorry - forgot to mention - th

Sorry - forgot to mention - there is also a "high speed jet" that provides the air/gas mix when you are throttled up. So it sounds like you have a slow speed problem...
 
"i myself have a 1961 40hp #35

"i myself have a 1961 40hp #35022 . i'm having the same sort of difficulty at this moment . run it at 50:1 . the knob above the butterfly is your richer (counter clockwise) and leaner (clockwise). the idler screw that you want is right below the butterfly . what i'm doing now is getting the motor so it is just running (on the vege of stalling out ). then adjusting the screw in . in very tiny amounts . and waiting for the motor to catch up . when it's running smooth , i'm repeating the process over until it gets to where i want it . once there tighten the inner nut so the screw doesn't move and leave it alone . your high idle i believe is the screw right above the slow/start/fast lever

tim

life begins where land ends"
 
"Firstly...Thanks for the sugg

"Firstly...Thanks for the suggestions.

Secondly...Obviously a novice question, but, does this motor have a generator on it?, or do I have to charge the battery myself? The only thing I have hooked up is the lighting and a small depth finder. I did have to "crank" the motor quite a bit before it decided to run, hence the concern for the new battery.

Thirdly...I have a Ev 28 hp, same year, in excellent condition. Both of the motors came with the boat. I am thinking of removing the 40, after I get it tuned, then running the 28, in order to make sure it too is in good working order. Can I use the same prop?"
 
"A generator, if it exists, wo

"A generator, if it exists, would be oppisite the starter on the other side of the carburetor.

The 40h prop will fit the 28hp but may have excessive pitch. Try it and see what performance you obtain.

Hard starting? If you have compression.... and spark that will jump a 1/4" gap with a strong blue lightning like flame... a real SNAP!, the most likely cause is that the carburetor is somewhat fouled OR very much out of adjustment.

Note that the carburetor that has a fixed high speed jet, located in the bottom center portion of the float chamber, must be cleaned manually in order to be absolutely sure it is indeed clean.

Depending on what carburetor you have (1 or 2 adjustable jets), the adjustments are as follows.

(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.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

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.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store
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(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.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

(Carburetor Float Setting)
(J. Reeves)

With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.

Due to age, I'd suggest that you use the alternatice spark plug recommended by OMC which is the Champion J6C plug, and gap it at .030.

(Point Setting Of Magneto Models)
(J. Reeves)

Set the points as follows. Have the flywheel key aligned with the fiber rubber portion of the ignition points. Adjust the gap so that a .020 gauge will pass thru but a .022 will not."
 
"Where are the jet screws? Th

"Where are the jet screws? The only adjustments that I see can be made are with the Rich/Lean knob, and the "screw" on the outside of the engine labeled "idle adjustment". It is located next to the "slow/start/fast" indicator on the port side, outside of the cowlilng, just above where the fuel line connects. I looked, but couldn't find anything on the carb that would be adjustable.

I assume that it is the stock carburetor, the engine serial # is 35022.

Again, thanks in advance!)"
 
"Oh..one more thing. Fuel mix

"Oh..one more thing. Fuel mix. I have confilicting reports of gas mix. I've read that 24:1 was used for '61 and older motors, and 50:1 starting in '62. On the access door, it states to mix 1 quart of either SAE30, or 2 cycle per 6 gallons of gas. That would equate to 24:1. Stay with that, or can I run 50:1?"
 
The " idle adjustment &#34

The " idle adjustment " is there to keep the motor from stalling if it runs too slow.Adjust it for a smooth idle in gear and keep it from stalling.24:1 is the mixture and it is why this motor is still around and not in the scrap heap.The high speed jet is a fixed jet and is not adjustable but must be confirmed clean.
 
your low speed adjustment is l

your low speed adjustment is located right below the butterfly . i use 500ml oil mix for a 6 gallon tank . haven't had any problems with that .just with the low speed idle like yourself.

tim

life begins where lands ends
 
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