1970 johnson 60hp i'm at my wits end

[johnnybass]

well i have a 1970 johnson 60hp that has been giving me problems , and i thought i had it solved but it seems it is not. first off let me list what has been done
rebuilt all three carb
link & sync
actually took off powerhead to check for some kind of exhaust blockage (no problems)
rebuilt fuel pump

At this point i am thinking it actually might be in the amplifier(the wires were corroded and i spliced in new ones)
symptoms= it seems to run fine in the driveway on muffs , last time i took it to the lake it ran out to the fishing spot and then back to the dock to drop off my friends.
at the dock i adjusted the idle and fooled with the low speed jets, then took her out for a spin. she ran good but not quite as good as previously, so i let her idle down and played with the idle and low speed adjustments and then , she was idling and just died and i couldn't get her started. so i limped back to the dock with my trolling motor. i tried starting her again before taking her out of the water and no go. after putting her on the trailer , i said what the heck and turned the key (fired right up!!!!!) so what the heck is going on , this i told to a local mechanic which led him to believe it could be some kind of exhaust blockage but after pulling the powerhead and the lower unit and coming up with nothing i am seriously confused!!!
at this point i am waiting for a gasket to put the powerhead back on and the lower unit. i am seriously baffled!!! any help would be great.

as far as the amplifier it looks to be stock unit and from what i can tell as far as compression and how the exhaust looked inside this motor although it is a 1970 i would say the hours are relatively low . also considering it was always a fishing boat and had a kicker bracket and small outboard since new.
i don't know wheather or not these amplifiers just go out or do they sometimes act up intermitedly
i am very mechanically inclined but just wonder if i might as well give up on this motor . i did find a 1977 johnson 140 hp freshly rebuilt for 500.00 so i am almost ready to give up and go that route.

 

[johnnybass]

Re: 1970 johnson 60hp i'm at my wits end

anyone ? help

 

[STARCRAFT16SS]

Re: 1970 johnson 60hp i'm at my wits end

Don't have a solution to your problem but....make sure when you put the carb cover back on(intake manifold) that you are not pinching your fuel lines....I've done that before...runs poorly that way

 

[johnnybass]

Re: 1970 johnson 60hp i'm at my wits end

just a question. if i do the CDI amplifier upgrade , does this require there new wiring harness?

 

[Daviet]

Re: 1970 johnson 60hp i'm at my wits end

The amplifier could act up intermittently or go out completely. Make sure all the electrical connections are real clean and tight. Did you by any chance check for spark when it stalled? You didn't mention what your compression numbers, what are they? What is your idle speed set at, 700-750 RPM with the boat in the water and in gear? You should not need to replace the wiring harness to replace the amplifier. Are you running surface gap spark plugs?

 

[SparkieBoat]

Re: 1970 johnson 60hp i'm at my wits end

i would love to help you..but I am completely ignorant of pre 79 motors, I just refuse to work on them at all.

 

[esco]

Re: 1970 johnson 60hp i'm at my wits end

I would look into the carbs, I know you said you rebuild them but I was facing something similar at the beginning of the season, My boat would run like a champ with the muffs on but as soon as I put her in the water, I got nothing... ended up limping it along as well. I had to have a carb job done cause all of the high speed jets were clogged. Perhaps yours just needs adjusting. Anyhow... Just food for thought.

 

[eavega]

Re: 1970 johnson 60hp i'm at my wits end

Have you verified whether its an ignition or a lean fuel problem? I'll assume you have verified good spark. If not, that is the easiest thing to check once you get your motor back together. Walk through your ignition system and test each component. I think you don't even have to have the motor running to test some of the components.

To check for a lean condition, you can use a spray bottle with premix in it sprayed into the carbs. If the motor starts running normally, then your problem is fuel delivery.

These motors have very few moving parts, and only need fuel, compression, and spark to run correctly.

Good luck.

Rgds

 

[johnnybass]

Re: 1970 johnson 60hp i'm at my wits end

compression is great 123 123 122, so good there , and before i had the problems spark was good i cant check it at this point until i get the power head back on. as far as the high speed jetting being a problem , that still wouldn't be a problem at idle. and my idle is set at 750 in gear , and as far as plugs i use champion ql77jc4 or ngk b7hs-10 i am really leaning to the amplifier, but as long as I am in waiting i am going to go through the carbs once more , maybe i overlooked something. this motor does have me worried however as i have been looking around for new points also and seems they are obsolete. i wonder if there is any way to change this over to a newer system sans points.

 

[05blastsrt4]

Re: 1970 johnson 60hp i'm at my wits end

thought I would share my experience, I recenty purchased a boat with a 71' johnson 60hp, when I first looked at it, it had been sitting for about 5 years, sprayed oil in the cylinders, fresh gas, and a battery and it started. After bringing it home it would not start, next day it would start. It pretty much started when it wanted to, but when it did run, it ran fine. After cleaning the carbs, checking points etc. I finally bit the bullet and bough a used amplifier. My engine starts every time now. So your problem very well could be the amplifier.

 

[johnnybass]

Re: 1970 johnson 60hp i'm at my wits end

i think it might be the amplifier and clipper, i have been checking into it further and after talking to the original owner again have been able to clarify a few things. he only used the boat for fishing, and for trolling he had a small outboard he would use so from day one this motor has not been worked very hard at all. and to his recollection he never had the amplifier replaced so we are talking fourty one years of use here. so at this point to be safer than sorry i am going to bite the bullet and pick up the new cdi unit. this morning i took off the flywheel and checked out the stator and distributer cap along with the points, and would have to believe the old gent I bought it from as far as how little the motor has actually been ran everything looked like new .

 

[johnnybass]

Re: 1970 johnson 60hp i'm at my wits end

well i went through the carbs again, and they are as clean as can be checked the high speed jets and they are marked 57. i might change them out as i usually do my boating at 4500 feet above sea level to 6500 feet at the higher mountain lakes. just wish the gasket for the powerhead would have showed up today.