"hot wire" a 1976 johnson 70 hp

[John90290]

I inherited a 1976 johnson 70hp and would like to get it into shape to replace an existing 70 that's has a leaking head gasket.

The "new" 70 turns over on starter fluid for a few seconds but i can't get it to run off of the small fuel tank.

Could it be the fact that I don't have an ignition switch or is that used just to activate the starter? I only have the one control box for the engine I'm currently using on my boat.

It has good compression (120 on all) but I wanted to make sure i did not need a control box to start the motor before i start to trouble shoot plugs, coils, carbs and such.

Thanks for the help,

-John

 

[jtexas]

Re: "hot wire" a 1976 johnson 70 hp

first, starter fluid has no lubrication.....it'll clean the oil right off the cylinder walls - if you wouldn't run it without oil, don't start it without oil - put some premix in a spray bottle......

if you had a keyswitch, with the key turned off, it would ground out the ignition and you'd get no spark - so that's not a problem

when you say "turns over for a few seconds" - you mean it actually starts & runs then shuts down?

Are you choking it?
Is the fuel tank vent open?
What's the compression?

 

[mikesea]

Re: "hot wire" a 1976 johnson 70 hp

it should start by just bringing power to the starter,and if the carbs are delivering fuel,it should run supplying its own ignition,but be sure its secure and has water,it will cook a dry impeller in seconds,however you should change it anyway since it was laid up,be sure you got you head together ,there is no way to shut it down without choking it and that will take a little time,be sure throttle isnt wide open or someone could be seriously hurt

 

[John90290]

Re: "hot wire" a 1976 johnson 70 hp

Thanks for the advice!

The impellar is the first thing i was going to tackle then, using the wiring diagram in my manual, i figure i would connect an extra ingnition switch to avoid any hazardous situations once she starts to rumble.


For the most part she looks like she lived a nice life on a lake by the lack of rust anywhere when compared to my current twin 70's living in the pacific.

Thanks again folks!!