TOPIC: 61 Evinrude Starflite III 75 HP Won't Start

I completed a 3 year restoration project of a 1961 Glasspar G3. I purchased it with the Evinrude Starflite 75 HP already mounted. I don't know if it was the boat's original power, but the previous owner had used it for the last 20 years or so before putting it dry dock for from 2005 to 2010 when I bought it. I ran the engine on it's stand once in March 2012 after rebuilding the carb and replacing the plugs, points and condenser. It started easily and idled right down. I ran it for about 15 minutes then shut it off for another 15 minutes and started it again to make sure it wasn't a fluke. It again started easily and idled smoothly.

Fast forward to July 2015. Just before launching the now refurbished boat, I test started the engine again. It started right up so in the water it went. It ran like a top hitting a top speed of 38 mph. My son and his family arrived in early August for a stay while I had to go home. My grandson went to take his Mother for a ride and could not get the engine to start. It is now mid-September and it still won't start. I've checked compression (100 lbs/cyclinder), rebuilt the fuel pump, replaced all of the fuel lines, and replaced the fuel pump pulse hose, disassembled and cleaned the carb to make sure it wasn't dirty. The fuel pump delivers fuel to the carb like clockwork. All four plugs produce good spark. But -- the darn thing won't start or even fire either with fuel or with starting fluid. It's killing me to see it sit after all the work I've put it.

Any suggestions out there?

I'm assuming the starter is turning the engine over it's just not starting. Check the safety switch by the magneto it could be stuck in or bad. It's controlled by the linkage. Mine went bad and I had the same problem.

Bob

I had a truck that would not start. It had fuel the engine would not even cough with extra fuel dropped down the carb or even either. The spark tester looked good. I put in a new module balist resistor distributor wires changed the timing chain. What it turned out to be was the plugs I had changed them less than two hundred miles before and they would not spark under compression they looked good out of the engine with a spark tester but would not fire under compression. They were autolite plugs. Funny thing told a friend about this and he had the same thing with the same brand. Sounds dumb but might be worth a try.

Thanks for the suggestion, Bob. The kill switch is new and the magneto is properly grounded. Besides, I'm getting spark at the plugs which I don't think would not be happening if the kill switch were bad or the magneto not properly grounded. Any other ideas?

This is intriguing. I replaced the plugs when I first started the engine several years ago and they probably don't have more than 4 hours total on them even now. Still, it's about the only thing I haven't replaced and having an extra set is never a bad idea. I'll let you know what happens.

Aw crap your right, sorry was still on my first cup of coffee.

Bob

How did you check spark? With plugs in boot, laid on the block? If so, it's possible the ign is weak and won't spark under combustion pressure.

A couple of ways to check this; if you have a timing light, with the plugs installed, clamp around a plug wire, crank engine and see if the light fires.

Or, take some old spark plugs and break/cut off the ground electrodes. Crank over with plugs removed; a good, hot spark will jump the resulting gap and be bluish/purplish. If the spark is more orange-y, that's weak.

If you don't have any extra plugs sitting around, just regap what you have to around .060" and see if spark will jump the gap and its color.

Does your 75hp have a battery-fired distributor (cap on top), or a magneto (cap on bottom)?

Mag coils are notorious for failing after heating up, then sparking a bit after they're cooled down (until ultimate failure).

HTH & Let us know what happens..........ed