I never met an outboard I didn’t like until now – 1960’s 40Hp Evinrude

[fleetwin]

OK, doesn’t even pop/fart when fuel is primed directly into cylinders, but you say there is hot blue spark. Have you tried the inline neon testers while cranking? Perhaps the engine is sparking while cranking, were the plugs out while you were checking for spark? Perhaps the key switch is funky, or maybe the vacuum switch is out of whack. You might try disconnecting the mag plate leads from the stop/vacuum circuits.
There isn’t much else that could throw the timing out of whack, the engine would surely pop/backfire if the plug leads were reversed. Maybe the carb throttle linkage is disconnected holding the throttle plate closed. I can’t imagine how the exhaust might have suddenly got plugged up either. I suppose it is possible that water is entering the crankcase/cylinders, you could try cranking the engine for a second while the gearcase is out of the water. Are you sure the fuel supply is clean/no water? You might try pumping some fuel out of the tank into a glass jar and letting it sit to see water separating out.
I supposed the engine could somehow be flooding (yes I remember you saying the plugs were dry though). You might try disconnecting the fuel line, draining the carb and letting the engine sit for a few hours, then priming the cylinders and cranking again with no fuel in the carb bowl.
But now that I think of it, perhaps we are overlooking the most obvious problem…Are the spark plugs new? Perhaps they are NG, try another set of plugs!

[rvpapasso]

Frank, if you read my original post the spark plugs were dry after extreme choking and injecting fuel directly into the carb. The amount of fuel I injected directly into the cylinders was enough to wet the plugs. I did not consider it excessive to flood the cylinders as I have done this before with success to get a dry motor going.

[chris-p]

I would start with new plugs.

Are you testing spark on an open air gap tester with the gap set to 1/4" or so, or are you holding plug to the block?

If to the block, perhaps you are being fooled into thinking the spark is good. Perhaps see if it will jump the appropriate gap, mimicking cylinder compression.

As you said, with good compression, and proper timing, she should at least pop after injecting a fuel/oil mix directly into the cylinder.

[frankr]

quote RVPapasso:

Frank, if you read my original post the spark plugs were dry after extreme choking and injecting fuel directly into the carb. The amount of fuel I injected directly into the cylinders was enough to wet the plugs. I did not consider it excessive to flood the cylinders as I have done this before with success to get a dry motor going.

With all the fuel you dumped into that thing, one would expect the plugs to be wet. You know for a fact that it had a bunch of fuel but still they weren’t wet. Doesn’t that suggest that too much fuel doesn’t necessarily result in wet plugs? I’d dry it out and try again.

[jcrigan]

Just a thought. How is the crank case compression?

[weedlessdrive]

I’ve had the clip on the fuel line flipped over before only to realize it a few hours later. But I assume you checked everything from the way it sounds. Good luck.

[retiredoz]

I just had a very similar experience on a ‘new-to-me’ ’90s Chrysler. Tester showed spark, no sign of life even after a direct injection of starting fluid.
Problem went away after tossing the virgin-looking Champions and putting in a pair of NGKs.
If you can inject fuel into the cylinders and not get even a fart, you have no fire. Motors will pop even if cross-wired, which says something will happen even if seriously mistimed.

[rvpapasso]

Thanks for the tips. I have brought many engines to life and really am stumped as the usual stuff isn’t working. Swapping to a second set of new plugs is easy. Just remember this engine just ran great twice in the barrel.

I tip I read that I did not check for is if the exhaust got clogged from critters nests. Could be the short run shook them loose. I would have expected still to hear a muffled pop but something I did not check for.

Keep those cards and letters coming until I figger’ this thing out.

[jerry-ahrens]

Have you checked the spark with a spark tester or just laying the plugs on the block? I would use a 1/4 inch air gap spark tester. A healthy ignition should easily jump the gap.

[Mumbles]

One more time, check and clean your ground wires no matter how pretty they look.

[Author]

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