Johnson CD-11 throttle/mag linkage question

[twostroke]

Gotta’ CD11 running last night that has been sitting in my shop for probably 20 years. It was clean and had good compression and cylinders looked good through Snap -On camera. Master plan is to restore eventually. Rebuilt carb, replaced top half due to choke linkage damage, new coils, points/condensers, water pump, resealed lower unit gearcase, etc. Timing/points are right on the money according to my VOM and pointer fixture. Started on 4-5 pulls, warmed up and ran really nice (low speed—in a tank), shifts nice, but shuts off as soon as the cam on the mag completely releases the throttle rod…which is a little faster on the twistgrip indicator than "Start". Is there supposed to be a rubber roller in the throttle rod where it contacts the cam on the mag like newer models (parts book doesn’t show one…) or do I have something out of time/adjustment in the linkage? Looked through my manual (albeit quickly) and didn’t find a lot.

Any help/info would be much appreciated. Thanks!

Jim

I say "pardon me" a lot. I had a 20H, then raced open mod sleds.

[RICK EICHRODT]

Sounds like the low speed fuel circuit is not functioning. Check for a broken needle tip stuck in the top of the carb. Remove the welsh plug on top to inspect.

[twostroke]

The low speed circuit is working; it responds nicely to the mixture screw. At the throttle position I’m describing above it’s idling nicely….hardly faster than trolling speed. That’s why I’m wondering whether I’m missing parts or have something waaay outta’ sync.

I say "pardon me" a lot. I had a 20H, then raced open mod sleds.

[1946zephyr]

I wouldn’t yank the welch plug just yet. Those motors don’t "lean sneeze" like the bigger motors. I would check the inside of the carburetor bowl and make sure debris hasn’t plugged up anything in the bottom. When these motors sit, the sediments will sit along with the old gas. I would see about getting a plastice float if possible, if you end up having to rebuild the carburetor. I’ve rarely ever had to rebuild any of those carburetors, but they can get plugged up in the bottom end, occasionally, when gas dries up and shellacs down there.
As far as the cam follower goes, that model didn’t have the roller at all. There was just a straight rod coming off the carburetor and it rides on the cam on the mag plate. Over time, a divot will wear into that cam and it will need replacement. The rollers were added in 1956. 1954-55 Johnson 5.5 was the only models without the rollers.

[twostroke]

Carb was completely apart, soaked in dip-tank and rebuilt just a week or so ago, and I put in a newer style plastic float. The low speed circuit is working….I could make it go into a rich ‘roll’, and lean it….and as I said…it idles nicely. I’ll have to retrace my steps tonight. As nice as it runs, it’s gotta’ be something stupid.

I say "pardon me" a lot. I had a 20H, then raced open mod sleds.

[twostroke]

Duh. I’ll bet I know what’s wrong. The original carb was broken where the square choke shaft slides in it, and some IDIOT (me….) replaced the top casting with one from a CD-12. I’ll bet that lever is a little different…. I’ll look tonight.

Thanks for the input….

I say "pardon me" a lot. I had a 20H, then raced open mod sleds.

[fleetwin]

Those throttle position indicators on the twist grip are not accurate, so please don’t judge the idle performance based on the twist grip saying it is in the "start" position. But, you seem to indicate that the engine craps out just as the throttle cam pulls off the cam follower, do you have the cam and follower synchronized correctly? There is a line on top of the cam, the cam should just start to open the throttle cam follower (throttle arm) when the line and follower meet. The throttle cam has two screws that can be loosened, so its positioning can be adjusted.
The engine won’t idle correctly if the throttle plate does not close completely at idle speeds. The engine will run rough/rich off idle if the cam starts to open the follower/carb butterfly too late.

[twostroke]

Thanks a ton…..I’ll bet that’s EXACTLY what’s wrong……because while I did get it to run smooth at an idle, I had the needle a lot leaner than I’ve had to set them on my other CD’s. I’ll check that tonight. Thanks again!

I say "pardon me" a lot. I had a 20H, then raced open mod sleds.

[crosbyman]

if you don’t have this link why not copy it for future ref. it contains all you need for your CD
http://boatinfo.no/lib/johnson/manuals/ … on.html#/0

you can store in PDF format by going to the bottom of the page an enter a series of pages ex: 105-115 that coverswhat you need then PRINT into a PDF file for storage on your PC

page 108 talks about cam follower adj. screws etc… as per Fleetwin instructions

Joining AOMCI has priviledges 🙂

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