1967 johnson 55hp

alcan · Dec 16, 2001

Iam having trouble with my 55hp johnson 1967.It starts,idles and runs fine.The problem is after 30 to 45 min. at wot it starts dogging down and dies. After a short cool down 5 to 15 min.the engine will restart.The shorter cool down the shorter the run time. I have replaced the water pump, thermastat and inspected cooling system also tested over heat sender and lite. All seem fine.Cylender head and exhust cover don't seem to over heat.The fly wheel gets so hot you can't touch it.I have replaced all ignition parts except points.Nothing seems to be rubbing,crank end play and seal are fine. I have been through the entire fuel system,it all checks out.What else is there?

petryshyn · Dec 16, 2001

Re: 1967 johnson 55hp

Hi alcan... >Does it startup immediately after it dies? >If it doesn't, is it slow cranking? >Is there spark when attempting to restart? >Is the primer bulb hard when it dies? G.Luck

petryshyn · Dec 16, 2001

Re: 1967 johnson 55hp

alcan · Dec 16, 2001

Re: 1967 johnson 55hp

Hello Schematic.No it will not start,only about 5 min.of set time.Then it will only run for very short time.The longer I let it set it will run a little longer.No it dose not crank slow at any time.I don't know about spark at time of death. I'am always away from dock, usually about 30 to 45 mins. No way to test.I can't seem reproduce problem tied to dock or trailer.I ran a 30 min test on the trailer.It passed,the next morning went fishin,it died,same mo. The primer bulb seems fine.

Rex · Dec 16, 2001

Re: 1967 johnson 55hp

I do not understand why the flywheel is get that hot. I first thought it might be the coils. When they cool off then they well start to fire again. Sould like you need to open your vent on the gas tank. But why is the flywheel get that hot?

MAYBE SOMEBODY ELSE HAS GOT THE ANSURE. GOOD LUCK REX A. HUBBLE

Rex · Dec 16, 2001

Re: 1967 johnson 55hp

Could be the points when they get hot the gap gets wider. Check to see if you got spark when it quits on you.

petryshyn · Dec 16, 2001

Re: 1967 johnson 55hp

hi again alcan : would be nice to know if you have spark.....but >check to see if any sensor is tied in to the ignition >does the charging system work properly. If not, I guess its possible that a shorted charge coil could cause excessive heat under flywheel which in turn could cause high resistance in mag coil primaries = no spark >when you replaced the coils, did there appear to be any oil around the top crank seal area? Were the points oily?

Rex · Dec 16, 2001

Re: 1967 johnson 55hp

Schematic I glad some one my see it the same as we do. For the flywheel to get that hot is what get me. What else could cause it? We need to know about the spark. You wound not think the starter is ingage do you? GOOD LUCK

alcan · Dec 17, 2001

Re: 1967 johnson 55hp

Wow thanks for the feedback Guys!I think I better add some more imput.This engine has electronic/point ignition.It also has 3 cylinders.When I bought the boat the motor was not running.I did'nt care.I have a few motors and needed the boat.The motor is mecanicly sound and looks nice to boot.It feels like low hrs to me. I begain to make repairs.I found the rotor and rotor cap were broken and cracked.The wiring harness turned to dust with every probe.I solved these problems,motor ran.Then the brain box went south.I installed one off a junk four cyl.it worked for a while.Bought a new ater market brain(cd box)I will test charging system and look into the starter to see if its hangin.I'll look sensors,but I am not sure what were lookin for.Could you mean somthing like the heat sensor crossing to shut down ignition?p.s.also installed new after market wiring harness.New coil,new spark wires.About those points,I havent replaced them as the OMC manual says they dont need replaced as normal ones do.I don't have equip.to test.How much ya think they'll cost? Also can't find a dealer, repairman who is comfertable working with system.Tecs too young or motor too old. I dono. Thanks again!

petryshyn · Dec 17, 2001

Re: 1967 johnson 55hp

Hi alcan: I apologize, I just assumed it was a mag ignition.I don't have a schematic of that exact year. How silly of me.... If its a CD ignition with points for triggering, it makes more sense. The charge coil or power-pack could be on its way out. *Use J.B.'s trick with the hair dryer to detect a bad pack. >start engine and let idle >heat power-pack with hair dryer until hot to the touch. If engine dies = bad pack. >if no effect, I'd get a schematic and determine the charge coil leads. >wait till engine dies on water, check charge coil according to manual. *If you can't get a manual, I can give you a generic way of testing the charge coil. Good luck

Rex · Dec 17, 2001

Re: 1967 johnson 55hp

I really hate to say this because of safty. Run it with the cover off. Why is the fly wheel getting so hot. I had a 1967 33hp. and the points was not that big of a deal. Check the spark when the engine dies. Just a spare plug in the boat and hold it to the block hook a spark plug wire to it and have some one to turn it over. I can't say anything else until you tell me if it has spark or not. R.A.H.

alcan · Dec 18, 2001

Re: 1967 johnson 55hp

Gentlemen,Thank you.I haven't had time to do any tests yet, its been stormy here,that keeps me hopin on my day job,getin ready for the holidays is takin the rest.Woe is me!Rex, running her w/o bonnet, Great idea!I've had a couple of motors in the past that were suckin exhaust gas.They would run great in the tank,put the cover on, put em on the boat and die.I'll probably have some time between the holidays if it don't snow.Schematic,I am sorry I am the one who was vague.But yes I have a model specific manual w/a schematic.Thats what makes me so #$@%^&.You would think a guy would have no problem.Anyway Thanks again and happy holidays.

JB · Dec 18, 2001

Re: 1967 johnson 55hp

Howdy, Gentlemen. Alcan, It looks to me like these fellows are taking you where I would take you, but I do have a thought or two to offer. This slowly dying behavior, including the time to restart determining how long it will go before dying again seems to me like a fuel starvation problem or a temp problem, not an ignition problem. What have you done to determine that the fuel tank is well vented? How about restriction of fuel flow? Try a substitute tank, hose and bulb. Your running problem may be unrelated to the hot flywheel. Prove that fuel flow is adequate, then go back to the flywheel heat symptom. Red sky at night. . . JB

Rex · Dec 18, 2001

Re: 1967 johnson 55hp

J.B. CORNWELL I ask hin to make sure the tank was vented. I have send alot people your way because I could not remembe the full story. Rex A. Hubble

G DANE · Dec 19, 2001

Re: 1967 johnson 55hp

I had a problem looking like yours, but on a smaller motor. When the ignition advanced, the magnets were barely touched by the flywheel. In iddle position, no problem. When i tried to crank, to control it, i could not feel anything, due to compression. When i removed the flywheel, i could see the coils and magnetos had touched. Remove your flywheel and look. !!!

petryshyn · Dec 19, 2001

Re: 1967 johnson 55hp

ditto g dane

suzukidave · Dec 19, 2001

Re: 1967 johnson 55hp

Maybe a dumb question but have you checked to make sure the engine cowling vents are clear? I've seen something similar that was apparently caused by a blocked cowling intake vent -- the motor would just die after a sustained run and take time to restart. I recall they monkeyed with the electrical for a while until they figured it out. I don't know if it was the carbs or the electrical that caused the stall but clearing the vent stopped the problem. Maybe its because you get poor air circulation inside the cowling which really heats everything up after running for a while and causes resistance in the wiring? Anyway, it was the same symptoms you describe including the delayed restart. I'm not even a backyard mechanic by the way so let one of these other guys comment on this before you take it seriously.

G DANE · Dec 23, 2001

Re: 1967 johnson 55hp

Magnetos touching coils - contd. Try to crank the engine while looking at the stator plate from underneath. If the plates moves when you crank, the coils touch the magnetos. The coils get very hot, and they will cause more and more friction. Coils can recover when cooled down, but are damaged anyway.

clanton · Dec 23, 2001

Re: 1967 johnson 55hp

It has a battery powered CDI with points for trigger. The stator under the flywheel is charging system only. It may be overcharging to overheat the flywheel, check charging system. The heat may be killing the condensors. The points for some of the engines with this ignition system were about 55.00 a set a few years back. My parts book list this engine 1968.

alcan · Dec 24, 2001

Re: 1967 johnson 55hp

Merry Xmas every one.I've been through the entire fuel system.New vent,vent hose,fill hose w/ground,cleaned tank,new delivery hose, new bulb,new conectors,new water seperator canister filter,fuel pump,cleaned carbs.I know the system works because it runs my kicker just fine,thats how I get home.Suzukidave no such thing as a dumb question.I've been hung up on those simple over looked things before.I will have a look.Clanton I have'nt had time yet to test charging system. My oem manual states, overcharged battery. Where to look? Alternator.Cause,extensive running w/o accessories.What to do?Hey turn on some accessories during extensive running.I don/t know about that.Clanton what would cause an overcharge? Would this overcharge cook my amplifier? Or the heat messin with the condensors take down the amplifier? Would this heat also be enough to crack the distributor cap? I'll look into this. Your probably right about the year being 1968. I'll look that up again as well. Thank you all and happy ho ho!

1967 johnson 55hp

Commander

Commander

Commander

Commander

Chief Petty Officer

Chief Petty Officer

Commander

Chief Petty Officer

Commander

Commander

Chief Petty Officer

Commander

Honorary Moderator Emeritus

Chief Petty Officer

Commander

Commander

Petty Officer 1st Class

Commander

Rear Admiral

Commander