1955 johnson 5.5 doesn't stay running lower than the start position

[Tech Tony]

Hello, I am starting a cd-12 after an overhaul and It runs rich and idles like on the slow position but it it on the start position. when turned down to the shift position it dies like it was the stop position..not to say it doesn't idle good, it does but I've tried adjusting the handle position, but it only goes together one way. it just wont run past the small mark on the cam for the carb lever, and it still has a good way to turn before it reaches stop.does anyone know what i may be doing wrong? when you turn down the throttle does it throw off the timing in order to stop the motor?

 

[racerone]

There are initial settings for the high speed needle ( lower ) one and the slow speed needle.-------But you as the operater need to fine tune these once the motor is on a boat and operating under load.---Have you done that procedure ??

 

[nabiul]

Can you rotate the handle as low as it will go and then take a picture of the cam and lever?

What about the timing plate linkage to the tiller handle? There must be some way to adjust it or maybe there is a low speed throttle limiting stop that needs to be adjusted.

Does your tiller handle linkage have something like this?

http://www.leeroysramblings.com/OB images/QD_idle_adj.JPG

 

[Tech Tony]

ok Im trying to send pictures, but I keep getting messages about the pic is over the 200 pixel of some such limit, ive had no luck tring to crop the pics. but anyway I rough set the high speed needle in the barrel by putting in gear and wot. set where it ran the best. no problem, i can even ser the low speed needle and it dosent run too rich and trolls good ecxept the throttle is on start and any attempt to go lower results on the motor turning off. when the throttle is on stop the cam plate is not touching the carb lever and is about an inch away from it. thats how sit was when i got the motor als so i think its the way it should be, very puzzling. I am about to tear down the carb and go through it again, then try to get a new low speed needle, i dropped and bent the tip when i was removing the little lever that was frozen on. i straightened and used 1500 grit sand paper to smooth out any deformations. but i'm not sure it is right as it is a precision made instrument.. next i will try seeing if i can fine tune the magneto plate after that I don't know...

 

[nabiul]

No Title

Use a third party image host like imgur.

As long as the lever starts to move when the mark on the cam comes around you are ok, if not then it is not set right.

Did you take a look at the video link I PM'd you? You can see that the throttle lever touches the cam even at low speed.

 

[lindy46]

The cam is adjustable - there are two bolts underneath (I think 5/16") which you have to loosen so the cam can move in and out. Adjust so the follower just starts to open the carb butterfly when it hits the mark on the cam. You can repair the point on the needle by mounting the needle in a drill, and putting the drill in a vise to hold it. Then use sandpaper or a point file on the tip as you rotate the needle.

 

[HighTrim]

Yes the needle is really just a faucet, opens up more or less. straighten as stated above and should be fine.

Some motors are just like what you state. The band on the tiller at the grip is a guide at best. If it idles fine, and gets up to WOT ok (carb butterfly fully opens and mag plate fully advanced) drive it and enjoy it.

 

[Tech Tony]

hi all, yes that is what I was afraid of, that it is what it is . but I'm sure when it was new it lined up right. High Trim, thanks for putting my mind at ease about the low speed adjustment needle. lindy 46, I will take your advice and use my drill press to smooth out the needle. nabiul, have a question for you, is the engine supposed to run at all when the small mark passes the carb lever? seems like it should even at the slowest speed. maybe some trash got in that orifice under the float needle, and also what makes the motor kill when you get to stop, on a motor that lines up right that is? does it kill because of the timing being disrupted, or something else? thank all of you for the great help.

 

[nabiul]

If I remember correctly, when you get below the mark on the cam the motor should still idle. And from my experience with an antique johnson HD25 when you get to stop the timing plate rotates and closes a built in switch underneath that grounds the ignition coils and kills the spark. Your motor may use a similar system.

 

[racerone]

No the CD models do not kill spark when turned all the way to slow.