1963 johnson 18hp questions

[wiboatergile]

Newbie here who found this forum very helpful with many of my questions.
What I have found out: the oil/gas mix is 24:1, plug gap.030 , plugs j4c ,
how to use seafoam.

What I want to learn: Rough idle or no idling-will seafoam help with this?
Lower unit lube suggested?
Appears to be no air cleaner between carb and where adjustment linkages are?

Got the Boat trailer and motor 2 yrs ago for $400.00 and a small canoe.
Took the guys word on gas/oil at 50:1, but really want to make sure everything is right. Oh and yes ran it Saturday in a tournament but it doesnt seem to have the power it should.
thanks for any help
Mark

 

[tashasdaddy]

Re: 1963 johnson 18hp questions

a carb rebuild should solve you problem, seafoam will not clean a dirty carb, it will maintain one. 24/1, gap .030 , J4C or J6C new plugs. parts are available at laingsoutboards.com check compression, rebuild the carbs, and use the following adjustments, high and lowspeed adjustment. i've had many of the old motors and love them, just refurbished a '58 35hp.
http://forums.iboats.com/showthread.php?t=167352

 

[wiboatergile]

Re: 1963 johnson 18hp questions

Thanks for the Info!!
Did the rebuild this morning and had to run some errands.. Decided to pull the plugs and check them and found the upper cylinder plug black and sooty. Lower one was clean. Would this be a condenser/point problem or fuel/carb cause? no luck in getting cover off inspection hole of flywheel yet. But plan on just changing them as not sure when it was done last, engine is almost as old as me....

 

[wiboatergile]

Re: 1963 johnson 18hp questions

Thanks for the Info!!
Did the rebuild this morning and had to run some errands.. Decided to pull the plugs and check them and found the upper cylinder plug black and sooty. Lower one was clean. Would this be a condenser/point problem or fuel/carb cause? no luck in getting cover off inspection hole of flywheel yet. But plan on just changing the condensers and points as not sure when it was done last, engine is almost as old as me....

 

[tashasdaddy]

Re: 1963 johnson 18hp questions

i would replace both sets of point, condensers, coils, plug wires, and the impeller. probably around $150, but you will have a dependable motor, before ordering check compression, and know you have a good base to work with. http://www.laingsoutboards.com/newp...ncludes Gale, Sea King up to 1963, and others

 

[F_R]

Re: 1963 johnson 18hp questions

A leaking fuel pump diaphragm will cause bad idle and flooding of the cylinder that it is mounted on.

 

[hammerhandle]

Re: 1963 johnson 18hp questions

Definitely change the lower unit oil,it will tell you if somethings wrong as if water comes out or metal shavings in the oil.You must use the marine gear oil, as it is designed for this application, it will somewhat "mix" with water if some happens to get in there and protect your lower unit to a certain extent.it will be a milky color.Im sure automotive stores would have it, i got the valvoline brand at meijers, and ive seen it at wal-mart as well, also change the "o" rings as well on the upper and lower screws, use teflon washers. There is no air filter to speak of it is called an air silencer and i dont see where it does alot of good if you ask me.I just rebuilt my 63' 18hp last year and replaced about everything that would wear out but i think ive got a very good engine.When i first got my engine i didnt know what the oil mix ratio was and all the manuals say from 64' on to use 50:1 .When i disassembled mine it had all needle bearings through-out the power head like a 64., no bronze or babbit bearings as did the older motors i dont know if 63 was a change over year and kept the same 24:1 to be on the safe side or what the specific reason is, maybe an expert can put light on this. Im currently running 40:1 synthetic and is running excellent.

 

[BoatBuoy]

Re: 1963 johnson 18hp questions

My '56 30-horse has all needle bearings on the rods and roller bearings on the crank. It has no babbet or brass bushings either. I still run 24:1 as I don't relish looking for 50-year old parts, nor paying the premium price, if it happens to come unglued. Oil's cheap. In later years, the metals improved, the oils improved, and the designs improved. These differences, taken as a whole, allow the use of 50:1. Yes, my con rods have needle bearings at the crank end, but perhaps they are made from steel not quite as good as the needle bearings in a '64 40-horse.

 

[wiboatergile]

Re: 1963 johnson 18hp questions

Talked with local Johnson dealer and changed the lower unit oil and screws/with the teflon washers. It was absent any debris. Plug wires were changed when I bought it.. ON a happy note I ran her till no white smoke came out and she perked up some. When restarted she fired first pull and ran alot better.. Using 24:1 mix with seafoam mixed at 1oz per gallon. Will replace points and condensers tomorrow and have new plugs onhand.. Thanks for the help guys and will let ya know how she does.. btw she idles well now that carb was rebuilt and reset per tashasdad recommended website..

 

[Walters]

Re: 1963 johnson 18hp questions

Newbie here who found this forum very helpful with many of my questions.
What I have found out: the oil/gas mix is 24:1, plug gap.030 , plugs j4c ,
how to use seafoam.

What I want to learn: Rough idle or no idling-will seafoam help with this?
Lower unit lube suggested?
Appears to be no air cleaner between carb and where adjustment linkages are?

Got the Boat trailer and motor 2 yrs ago for $400.00 and a small canoe.
Took the guys word on gas/oil at 50:1, but really want to make sure everything is right. Oh and yes ran it Saturday in a tournament but it doesnt seem to have the power it should.
thanks for any help
Mark

I too am a newbie here but would like to say thanks for all the amazing information already.
Thought my 1963 Johnson outboard FD-17B was running a little rich. I am going to have to try the 24:1 mix as I am currently running 50:1 and getting a tonne of smoke.
Also, I do require a top cover if anyone may have one for sale or know where I might find one.
Thanks Again!!!

 

[dalejiw25]

Re: 1963 johnson 18hp questions

For the FD-i7 you can use a 25 h.p. hood from the same year if that will help you in your search. Gives you 2 options to look for anyhow. Good luck.