'77 Johnson 85hp wont turn over

eterry

Petty Officer 2nd Class
Joined
Jul 8, 2006
Messages
113
This is strange! I was working on my boat today, geting ready for tomorrow, and replaced my nautical lights as they were bad. While working on lights I checked motor for power to rule out battery problems and motor bumped over fine. Got lights on and was gonna start motor and run some seafoam thru it. Hooked up muffs and hit elec. choke, they shut but motor wouldnt turn over! Tried to crank it a couple more times and nothing, choke even stopped closing. Thought battery was down so put my charger on, set for boost, still nothing! Am charging battery now, shows over 60% charge. Lights and horn work, but thought if battery was down the choke would at least engage. What gives? Boat has been on lake twice this year, last about 6 weeks ago. Battery is less than a year old. Ignition switch? Starter?
Thanks,
Eterry
 

eterry

Petty Officer 2nd Class
Joined
Jul 8, 2006
Messages
113
Re: '77 Johnson 85hp wont turn over

I read some other posts here to help troubleshoot, I went out and hooked the positive jumper cable to the starter, then grounded it and the starter turned over, though it didnt engage. I am thinking it may be the ignition switch, thoughts anyone??

Eterry
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: '77 Johnson 85hp wont turn over

there is an inline fuse near the starter solenoid, in a red holder (20 amp) it controls the starting circuit, and choke. also--
90% of starter problems are bad connections. remove and clean both ends of the battery cables, so that they are shiney, also the cable from the solenoid to starter. check for nicks in the cables. and make sure the connectors are on the wire good. the cable tend to corrode from the inside out, if nicked, corroded wires, and connections, heat up and cause resistance to the follow of electricity, thus the starter doesn't get enough. you can also take jumper cable pos battery post to large post on starter. with a good connection, the engine should spin. then if the starter is good clean everything and retest. then trouble shoot solenoid. starters can be rebuit at a starter/alternator shop, much cheaper than a new one.

also have the battery load tested at the auto parts store, free, i've had new batteries go bad
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: '77 Johnson 85hp wont turn over

i hope you are wiring you lights and accessories, totally separately from the motor circuit. if you pick up power from the control, that will blow the fuse.
 

eterry

Petty Officer 2nd Class
Joined
Jul 8, 2006
Messages
113
Re: '77 Johnson 85hp wont turn over

Thanks for the help Tash, I looked at the red connector last night but didnt see a fuze, will look again and see if i missed it, was almost dark when i looked. Will check connections and take battery in for test. I just replaced old nautical white light, used old wiring to put in new light and switch on existing wiring so that shouldnt be a problem. I had just hit the ignition and it turned over an hour before it wouldnt work, its a little boggling. The starter turned but didnt engage using the jumper cables directly on starter, was it not enough voltage to engage bendix? Am really scratching my head here....

Eterry
 

eterry

Petty Officer 2nd Class
Joined
Jul 8, 2006
Messages
113
Re: '77 Johnson 85hp wont turn over

Well if you think you know everything, go out and buy yourself a boat!! This is a learning experience for me and a humbling one. I thought there's no way the battery post/terminals could have corroded; the battery is less than a year old. I have been dealing with motors and batteries for over 25 years and terminal post dont corrode that easy, even if they did it wouldnt be enough to keep a motor from turning over, right ?

WRONG!!!! I took Tash's advice and cleaned the connectors, there was a SMALL amount of rust under the positive connector and post. Hooked it back up and started like a champ!!

Tash, whatever you drink I owe you a bottle!!

Lakebound~!!!!

Eterry
 
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