TOPIC: 1962 Merc 1000 mystery

The beloved merc 1000 on my beloved Glasspar G3 has seen better days.

I'll start at the beginning so we have a full medical history to work with.

Two seasons ago, after two summers of beautiful running, the crankshaft went kaput. I didn't have the time or the funds to get it fixed right away, so it sat for a season and was fixed over this past winter. Once all fixed, I took her out and she flew perfectly. Once around a small lake (about 20 min), then another time around...well only 7/8s around because all of the sudden it started losing power and we had to putt-putt home on what seemed like three cylinders. Lo and behold, we ran a spark test to find only three cylinders were firing. Well maybe one of the coils? Perhaps a resistor shorted? Lots of thinking and 3 rebuilt carbs later, the suspect was apprehended, and the spring in the point was broken. Once replaced, she fired right up and sounded good...on land. Then it was back to the lake. Problems: the fast idle cable/setup somehow shifted and really didn't do much, so starting it was tougher than normal. Opened everything up, readjusted the fast idle so it actually did something, and back on the water we went. Well it started up really nicely but when I shifted into forward....dead. Well let me adjust the fast idle screw...and adjust it...and adjust it. It would still die, and die, and die.

Back to the drawing board. Well if that was a 20 pitch chopper prop, let me throw on a smaller prop just to see if that makes a difference.

A two blade 15 pitch prop on the tower of power and suddenly I could shift into forward. It actually ran very nice with that prop, starting, accelerating, even a WOT rpm of about 5200. But something still wasn't right if it used to spin a 20" chopper at 5400. It seemed to me like I was running on 4 cylinders. Maybe fuel lines are plugged? Checked that..nope.

At this point frustration became real. Let's just start disassembling everything until we find something wrong. A lot of wrenching later, I pull the float bowl cover off of the middle carb...the little spring on top of the float bowl cover had become stuck on the pin/flap assembly on the float cover. This might be it! Put it all back together and turned the key....she roared. So back to the lake. Started right up and was idling much faster than before so I dialed the screw back a bit to get it just right. With that same 15" two blade prop on, it shifted right into forward, planed out, and ran. At least this time it got to 5200rpms before actually being WOT. Maybe it's fixed, let's put the chopper on. Chopper on, had a bit of difficulty shifting into forward without it dying but it was possible. Very tough to get up on plane, but it did plane out. Yet the motor would only spin the prop to 3000 rpms...not even close to the 5400 it could once do. And at this point, I gave up. Pulled it out, went through the winterization process, and tucked everything away.

So I have come to you in search of great mercury wisdom, and some brainstorming to diagnose my once admirable merc/G3 combo.

I appreciate everybody's time very much, thank you all in advance.

-Ben

Check your point setup. they have to be setup just correct to work right.

I suspect points as well. Dwell or sync. Also check fuel delivery from the tank.

Hey Ben,

Not sure what year your 1000 is but I'm curious if it has crankcase bleed check valves and if you looked at them.

Thanks,
Terry