CD-14 requires full choke for idle and run

[greenie727]

Gentlemen,
Just picked up a nice low hour Johnson CD-14 with original pressure tank. Previous owner replaced both coils and pump impeller. Brought it home and test tank run required full choke to keep engine running at idle and any throttle setting above idle. Without any choke engine will stall out. Engine builds and tank holds good pressure. Previous owner claimed he coated original carb float with shellac. I will remove carb and install new carb kit. Is it likely that newer ethanol fuel blends deteriorated shellac coating and plugged main jet and low speed needle passages? Any other suggestions at what to check for this symptom? First post on this great website. Thanks in advance for any help.

[chris-p]

I have seen many floats that were "coated" with who knows what, and when fuel contacted it, the coating melted off.

Regardless, you have to open it up. It is running WAY too lean, likely due to a restriction like you think, or an air leak somewhere.. You have adjusted the needles correct>>?1.5 turns out from seated for the low, and 3/4 for the high, then fine tune on the water.

[greenie727]

Thanks Chris,
I will remove the Hi / Lo adjustment levers and check turns out from seated. I think a new float and carb kit with gaskets and needle packings should help. Just love the holiday bronze and cream color with excellent sea horse badge on this motor.

[jeff-register]

Greenie,
Use some power tune from OMC or Merc. Spray enough to soak the carb body. It may take two cans but it will not hurt any plastic parts but it will clean the small passages in the body. it may be pricey but very good for cleaning. A friend who is in the Mercury business uses the power tune for years now. He saves the used fluid & runs it thru a oil filter & reuses it.

[greenie727]

Thanks Jeff,
I might give it a try before I pull the carb to disassemble, clean, and install new carb kit.

[beerman57]

Greenie, you need to disassemble the carb and do it right, get the power tune with the long, small spray tube, spray it in all openings and let it sit for a while, then spray every opening again before flushing it out and blasting everything with compressed air.
Jeff, 2 cans? What size are you buying? Is there a .5oz. size? That’s strong stuff and it doesn’t take a lot.

[1946zephyr]

If your float turns out bad, you can get a plastic one through marineengine.com. With todays fuel, it’s hard to find anything to hold up. A lot of people like to use model airplane dope.

[greenie727]

Thanks everyone for all the replies. I have ordered the carb kit (0439071) with float from Marine Engine. Is it absolutely necessary to remove the factory original welch plug on the top carb body above the high speed nozzle? I always worry that the new plug supplied with the kit will not seal as well as the factory installed plug.

[Doug Wilson]

That is your call, I have not taken any out, and not had a problem. If you soak the carb. good can usually get away with it. There are many on here that will disagree with me but that is my method.
Have used model airplane dope on several carbs with no problems so far with 3 or 4 coats on them but I always run ethanol free fuel too.

Doug

how is it motors multiply when the garage lights get
turned off?

[fisherman6]

I usually do not bother pulling the welch plug as long as I am able to get plenty of carb cleaner to pass thru the ports in both directions. I have pulled a number of them when doing carb rebuilds and rarely find anything behind those plugs. I have never found more than a trace of fine debris inside that cavity. Unless I’m chasing other problems I cannot figure out, I do not pull them anymore.

When replacing the welch plug with a new one I do seal them up with clear nail polish just to be sure there is no leakage. I have never had a problem with one leaking unless the pocket was buggered up. If you do end up pulling the welch plug, be VERY careful when drilling the pull hole in the center of the existing plug to not let the drill touch the carb body when it breaks through. 😉
-Ben

OldJohnnyRude on YouTube

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