1975 Johnson 50hp motor troubles

[Daviet]

Re: 1975 Johnson 50hp motor troubles

OK, I think I under stand your problem. Your lower unit has a pump in it to assist shift. The motor has to be at idle speed for it to go into neutral. When you get it to start, have someone watch the prop and see if it goes into neutral within a second or two. I may have asked this question before but do you have a factory manual for your engine, it will explain the operation of the lower unit.

 

[Daviet]

Re: 1975 Johnson 50hp motor troubles

It almost sounds like the shift rod is out of adjustment. Give me some time and let me see if I can locate a manual for your engine and do a little research.

 

[Starcraft Tony]

Re: 1975 Johnson 50hp motor troubles

Thanks for the info Daviet, I dont have the factory manual, when I bought the boat the previous owner provided me with a Seloc manual.....so far its been alright. I tried to get her started today. Just for giggles I hooked up a different fully charged battery and redid a compression test. Both cylinders are up to 95 (guess its time for a new battery). Hooked everything back up and tried to start. She seemed like she wanted to start so i fed in some fuel and she would sputter and almost start but then she wouldnt.

FOUND A NEW SYMPTOM While trying to start her for two or three min. i noticed smoke coming from the red battery wire, Of course I reached down and touched it and it was blazing hot Checked to make sure I didnt cross connect and I didnt, What could be going on here? short somewhere?

Thanks

 

[bktheking]

Re: 1975 Johnson 50hp motor troubles

Doesn't sound like a short, typically running a starter for two - three minutes will cause things to start to get hot, did you try for 2 minutes straight?

 

[Starcraft Tony]

Re: 1975 Johnson 50hp motor troubles

No only cranked it for like 10sec. Seen the smoke as soon as i started to crank, stopped and so did the smoke thought maybe i got something wet when hooking up the muffs, but nope. Started craking, and again smoke, went and grabbed a hold of the wire and it was fire hot.

 

[Starcraft Tony]

Re: 1975 Johnson 50hp motor troubles

Well I've given up on the hot wire, I looked around and didnt see anything touching so I must of been crakin longer then i thought. Anyways, the good news is i got the motor started (thanks for all the advice Daviet) . She sounds good. Replaced fuel line, sprayed some fuel into the crabs and she finally turned over. Let her run for a while shut it down, and started up no problem, let it sit for a while and started up no problem.

However all is not good as my prop issue still remains. She is spinning really fast, fast enough so that I dont want to stick anything in there, and I dont have the guts to put it in any gear other then netural in fear of doing more damage. Anybody have an idea whats going on here?

Thanks

 

[Starcraft Tony]

Re: 1975 Johnson 50hp motor troubles

Well I got the guts to cycle the boat through the gears to see if the prop would stop and when I came back to netural the prop nearly stopped. She spins freely when shes off now too, who knows? i'm just glad shes runnin again.

Thanks to all of you who chimed in with your advice.

Have a good and safe holiday weekend

 

[papasage]

Re: 1975 Johnson 50hp motor troubles

the hot wire while starting was probabley a loose cable or bad connection . that will cause a hot spot. 1975 doesen`t have a pump assisted shifter. that ended in 1972 or 73 . glad you got it running .

 

[SparkieBoat]

Re: 1975 Johnson 50hp motor troubles

sounds like a bad connection or the wire is too small...What size is the wire??
also I read your process of the head gasket replacement..
I did not see where you sanded the head down as mentioned in an earlier post..if the motor overheated it probably warped your head slightly. You really want your compression over 90...120 is what you really want. removing your head and sanding it smooth should help...also spray your pistons down with some deep creep of sea foam. hit the rings good..I think everything with your foot is ok.

good luck Sparkie

 

[classicjohnsons]

Re: 1975 Johnson 50hp motor troubles

Did you pull the corner of the housing where the wires go into the motor (i belive it is one bolt)? If the wire is bald it can ground out make you engine look like it is on fire and heat up the wire..