Johnson 25EL758 Ignition timing?

[foghead]

Does anyone out here have the specs and methods for timing a 1975 Johnson 25EL758? I just rebuilt the carb and I'm thinking that the linkage is somehow tied into the timing of the motor... can someone pleeeeez help me with this? Nobody around these parts has a clue about these older motors...

Thanks to any and all for help!!

 

[Cofe]

Re: Johnson 25EL758 Ignition timing?

With motor off.
Throttle all the way down. The roller above the carb needs to line up with the mark on the throttle cam. Carb butterfly all the way closed.

With motor off.
Shift into forward, throttle at WOT. The roller has picked up off the throttle cam. Carb butterfly horizontal.

Adjust linkages to achieve these results...... Hope this helps out.

Model #for your motor is 25EL75B........They are hard to read sometimes.

 

[foghead]

Re: Johnson 25EL758 Ignition timing?

Thank you so very very much!! It almost seems as if every one of these motors has a different procedure!

I'll git 'er dun first thing in the morning and see whee it gets me. Should be just about read for it's first voyage in 15 years then!

TY yet again!!

(Correct model # also duly noted!)

 

[Cofe]

Re: Johnson 25EL758 Ignition timing?

15 Yrs?

You should read awakening a sleeping motor in the sticky.....top secret file at the top of the forum.....lots of good tips......

 

[foghead]

Re: Johnson 25EL758 Ignition timing?

TONS of good info in that sticky... The motor will get a new fuel pump, vacuum hoses and water pump rebuild. All common sense items that were just kinda foreign to me when it comes to these little motors... the cylinders got a nice blast of 2-stroke oil before I tried firing it just to make certain that the walls were lubed a little.

Now to find a manual for the little bugger...

 

[Cofe]

Re: Johnson 25EL758 Ignition timing?

The best manual to get is a OEM manual.....preferably OMC......you can sometimes find them on ebay.

 

[foghead]

Re: Johnson 25EL758 Ignition timing?

Thanks again Cofe... motor timed out beautifully, lower oil in the gearcase looked perfect when I replaced it... basically, a fuel pump rebuild, vacuum hose replacement and impeller replacement are all that's left to do to make the motor tight.

Very funny thing - this motor uses the idle screw (a crappy little plastic insert thing that doesn't hold up at all) to control BOTH the idle and the timing. A steel screw with a jam nut is going in its place with plenty of adjustment room left on the throttle control and cable.

I've found that the more simple the design, the more critical every specific part is... this motor is VERY simple.

Once again, thank you!