1963 Johnson 75hp

[Da Bull]

I`m working on a 1963 Johnson 75hp V-4. Does anybody know the ballpark compression?

[Dave S]

Don't know.....if all close...... good Nu'f.....Is a eltric shift ?.....

[Capt.Insane-o]

if it's dumping as much gas as it burns in the water it's perfect.

[Dave S]

Cut the block deck surface so piston is even with the deck.......them motors had no squish band.... thats why they wasted gas..... Here we go........Put a 140 PH under the hood.........

[Da Bull]

Yes electric shift. Yes it dumps lots of fuel into the lake.

[FUJIMO]

Yes electric shift. Yes it dumps lots of fuel into the lake.

...perfect. thats the way theyr'e suppose to run.

[FMP]

Nice Pair was working on one, few yrs newer. They had that temp heated choke, burn a gallon on warm-up and idling away in 3 minutes.

[Capt.Insane-o]

I rebuilt/restored a 1967 65 hp years ago and it was 115 psi with new internals.

[Da Bull]

Got her running pretty smooth with little smoke.

[Da Bull]

Nice Pair was working on one, few yrs newer. They had that temp heated choke, burn a gallon on warm-up and idling away in 3 minutes.

Yep same thing here.

[FMP]

I like Dave S's idea, tighten it up a little if possible.

[racer]

Those had 85 to 90 on my snap on gauge when right. They do waste a lot of fuel.

[keith scotton]

A friend bought a wood runabout with one of those on it wanted to go skiing. Put boat in ran out to his favorite spot not far. Got him up skiing about five minutes motor quit. Hit the key motor spun did not start went to the back of the boat reached down grabbed the 6 gallon can from under rear splash well about did back flip over the side can was bone dry. Not what I was used to in fuel consumption.
Enjoy Time at the Pump Keith

[FMP]

Down draft set up on that? Build a new intake and set a small Holley 4bbl on it, probably use less gas.

[Dave S]

Or...... a v4 suzzikee.......