Johnson 6HP Problems

[HantsCounty]

Hi guys, new to outboards, have always used trolling motors on my little boat but just bought a 6Hp 2 stroke Johnson, not sure of the year but it is an older unit. I bought this last night and seen it run in a bucket with no problem. Took it out on the lake today.... Was a little hard to start, but once it started I could keep it in high RPM, getting the RPM's up very high and motor seemed to run fine. No way it would idle... Once I switched it into gear it would die out unless I put the throttle up as high as it would go. Once moving on full throttle it would not get very high RPM's at all and it would run very slow, almost a fast walking speed, this is as fast as I could get this going. But once I took it out of gear I could get the RPM's up very high, in gear RPM;s would stay low no matter what, and will die out if I turned the throttle down at all from fast. Any ideas? I have a camping trip planed for tomorrow and need this to work, if not need to make different plans.

I was told to mix gas to 40:1

 

[nwcove]

Re: Johnson 6HP Problems

sounds like its running on one cyl and/or needs carb work. try pulling a plug wire off while its running in a barrel, see if it makes a difference, if no difference put that wire back on , and pull the other one. whats the model # on the tag on the transom clamp?

 

[HantsCounty]

Re: Johnson 6HP Problems

tag is no longer on the motor. Could running on one plug be just due to dirty / bad plug, or a further electrical problem?
Thank you very much for the quick response!

 

[nwcove]

Re: Johnson 6HP Problems

have a look on the powerhead, there should be a nickel sized aluminum plug, it should have the model # stamped on it. IF it is running on one cyl, it could be a fouled plug, bad coil, etc ect. you first need to do the simple test to verify.
a pic or a model number would help figure out what you mean by "older unit". ( i personally dont consider anything newer than 1975 an "older unit" !! lol) are you in hants county N.S?

 

[HantsCounty]

Re: Johnson 6HP Problems

Yes Sir, I am in Windsor, How about yourself?

So did your spark plug test, checked gap and cleaned them up, switched the two, the top cylinder is not firing. The one spark plug on top is not working, I pulled the plug ontop with no difference, plugged it back in and took out the bottom plug and engine dies, Switched the plugs and had the same results. The Model or serial # that was on that cap is 00002979

So what am I looking at next if the top cylinder is not firing?
Thanks again!

 

[nwcove]

Re: Johnson 6HP Problems

its tough to help without knowing what year the engine is. do the plug wires go to external coils?...or do they go up under the flywheel? a few pics of the motor...cowl, and powerhead could help narrow down the year.

( im in hubbards. small world!! lol)

 

[HantsCounty]

Re: Johnson 6HP Problems

I will take some pics here in a minute, but the two wires run up under the flywheel. My folks live up in chester!

 

[nwcove]

Re: Johnson 6HP Problems

sounds like it has the older universal ignitition then. not to bad /expensive to fix. i work out of chester..may know yer folks if they have been in the area for awhile!( but a compression test will tell if the motor is worth spending money on.....uap/napa usually will rent a tester cheap for a day)

 

[HantsCounty]

Re: Johnson 6HP Problems

Buddy did say it was rebuilt not too long ago, I would like to fix the problem regardless! if its cheap and or easy id like to just go ahead and do it anyway. So what should I be looking at to get this fixed up?
My parents have been living in Chester for 5 for 6 years. They have a sail boat they sail out of Chester, its at the big marina there.

 

[HantsCounty]

Re: Johnson 6HP Problems

maybe condensers and points? any idea where I would get them here in NS?

 

[nwcove]

Re: Johnson 6HP Problems

you need to do a compression test before spending any money on it. as mentioned. uap/napa will rent a comp tester. dont throw money at it before the comp test. ( i do have fond memories of chester "race week"....its quite an event for the sailors!!)

 

[HantsCounty]

Re: Johnson 6HP Problems


just ran out and grabbed the neighbors tester, its in PSI and says 85 PSI?
those are some pictures of the motor.

 

[HantsCounty]

Re: Johnson 6HP Problems

is 85PSI going to be ok?

 

[Davem3]

Re: Johnson 6HP Problems

85 PSI is just fine, i have the same exact motor and mine is a 1968 with 90PSI.........
the plate should be on the port side of the outside transom mount............

fuel mixture is 50:1


okay, check for spark on both cylinders first.............
never mind, i had a senior moment here

under the flywheel, check the coils, condenser, and the points, gap is at .020, see here:
http://www.marineengine.com/parts/j...5R&manufacturer=Johnson&section=Magneto+Group


after that is fixed, look at the fuel lines, i replaced mine made them E-10 friendly.
it looks like the thermostat housing was done recently, take it back apart, and look for the thermostat, it does make a difference, and check the impeller as well, get the NEW kit with the SS insert...........

also, it might be a good idea to rebuild the carb as well, the float cannot be in good shape, i bet.........

my model number on my 68 is CD-25R that should help you tons...........

and mine is immaculate like yours, all original stickers in place and NO scratches either, enjoy that motor, she is awesome

 

[Davem3]

Re: Johnson 6HP Problems

oh, and welcome to Iboats, Sir ................

the only thing worrying me is that that motor was overheated at one time .................

hence the water thermostat/ impeller questions, advice

 

[HantsCounty]

Re: Johnson 6HP Problems

excuse my lack of knowledge with this stuff, as this is the 1st outboard I have had to work on. Used to vehicles etc. How do I check the coils, condenser, and the points to see if they are faulty? Just by looking for cracks etc?
will I need a Harmonic puller to get the flywheel off? Thanks alot! I hope I get to enjoy this motor!

 

[HantsCounty]

Re: Johnson 6HP Problems

I take it you think this is a 1968 or around that model? It does not have the plate on it anymore. just the 00002979 on the coin looking plug. Am I expecting too much by thinking I can get this running with two cylinders for tomorrow?

 

[SeaKaye12]

Re: Johnson 6HP Problems

Chances are you will just need to clean and re-gap the points. You can visually inspect the coils; if they are cracked they are almost sure to be bad. Condensors rarely give trouble but replacing them is pretty much the only remedy; they are inexpensive.

Also just check over all the wiring for good connections; especially the spark plug wire. Sometimes they can be salvaged by cutting 1/4" from the ends t0 freshen up the connection a bit.

And; yes....the harmonic balance type of puller is the one to use.

Your spark plug wires are not original. I imagine that you will find new(er) components under the flywheel and simply dealing with dressing the points will fix things up.

 

[HantsCounty]

Re: Johnson 6HP Problems

awesome, thanks guys. going to go grab a puller now and take a look at this thing now. Fingers are crossed its just the points. Am I able to use a spark plug gaper for the points? and to .020?

 

[AlTn]

Re: Johnson 6HP Problems

feeler gauge for the points....for a quick clean allow the points to close on some sandpaper/emery cloth..200 or finer...and pull the paper through a few times the clean the points with some acetone, spray carb cleaner ,etc...try to avoid getting it on the points cam as it has a light coating of oil on it to prevent premature wear of the rubbing block on the movable points arm...add 1 drop of a light oil to the wicks you'll see, or should see, on each point set... the flywheel puller will require 1/4"x20 tpi bolts grade 8 preferred as well as some grade 8 washers...the water level in your barrel should be higher than it is in your pic by 8" or so, just a few inches below the exhaust relief holes < nostrils > on the rear of the exhaust housing...google..leeroysramblings.com..6 hp. repair and maintenance as you'll find a lot of info there...good luck on a quick spark return, sometimes these things take more than one attempt