1964 40 HP Johnson get my gun please!!

[BLDINGNSPECTOR]

Will start up but no rpm's. Plugs constantly fouling. Ran compression test about 110 psi per cylinder. Installed new points, new condensors, new wires, new magneto etc. changed gasoline from 87 octane to 90 octane, checked oil gas mixture 1:50 . New plugs, still putt, putt, putt, help this tired building inspector with hardly any money??

 

[12Footer]

Re: 1964 40 HP Johnson get my gun please!!

I werk for the city myself, so "I feel your pain".<br />Go back to 87octane on your next tank.<br />Remove the exaust port plate and clean all the carbon out of it. I highly suspect this motor cannot breathe. More acurately, it can't exhale. This is a common problem.<br />Decarb the engine after you have physicly opened up the exuast ports,(combustion chamber on out).<br />Also,your compression is good,and will improve after cleaning the coke out of it.

 

[Walter]

Re: 1964 40 HP Johnson get my gun please!!

If you are mixing your fuel 1 part gas to 50 parts oil then I think I know why your plugs are fouling! Hee, hee... I'm sure you meant 50:1 At least I hope so!<br /><br />Most likely that engine began it's life burning a much richer mix than what today's new oils allow us to get away with. So I'd suspect 12 footer is right on the mark by saying she's probably majorly choked up. Even if that's not the problem...it sure can't hurt to give her a good cleaning. Do that, and let us know how things work out.<br /><br />Good luck...<br /><br />Walt

 

[Chinewalker]

Re: 1964 40 HP Johnson get my gun please!!

Hi Inspector,<br /> Another thing to check is that you're getting full magneto advance and that the carburetor butterfly is opening all the way. Those old big twin OMCs had a rather convoluted throttle advance linkage that occasionally would loosen up. Carb butterfly should be more or less horizontal at WOT.<br />- Scott

 

[SeaMasterZ@aol.com]

Re: 1964 40 HP Johnson get my gun please!!

arent these old timers supposed to be run at 24 to 32 to one?<br /><br />Joe Reeves has made the point (and its a good one IMHO) that those old motors are still around cause they had plenty of lube, made em wear out proof ... so you smoked a bit, smoking was cool back in those days!

 

[Hooty]

Re: 1964 40 HP Johnson get my gun please!!

I'm not sure about that year engine but if it has inserts instead of roller bearings, it might should stay at 24:1.<br /><br />c/6<br /><br />Hooty