1968 3hp Johnson

racerone

Supreme Mariner
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Dec 28, 2013
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37,815
I can not touch / hear your motor.----Perhaps flywheel is rubbing on the coils and making the chirping noise.
 

film495

Petty Officer 1st Class
Joined
Apr 8, 2009
Messages
285
I can not touch / hear your motor.----Perhaps flywheel is rubbing on the coils and making the chirping noise.
I'm betting on the carb. probably put 4 or 5 hours on it this weekend, I'm going to run it some more with the 24:!1 gas, and just set it at some steady trolling speeds, and see how consistent it runs, and check the plugs after.

The tapping noise is either piston slap or I'm hearing something in the exhuast, but you have to try to hear it, so - most likely just normal motor sounds.

When I eventually get the nozzle out of the 3hp carb, I'll be keen to test it out. Not sure how to get the nozzle out without breaking it and drilling it, maybe I'll put it in my freezer for a while ... lol
 

film495

Petty Officer 1st Class
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Apr 8, 2009
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285
got that nozzle out. the end is buggered, but it could probably still be used, but I got a replacement I'll use. another piece for the odd parts bin. I heated it up good and applied solvent and penetrating oil, let it sit, heated it up again an hour or so later and applied more penetrating oil, and then worked it back and forth with vice grips, just hard enough so the grips wouldn't slip. took about 5 minutes of just applying back and forth twisting force and then it started to move a hair and a couple minutes later it was out. I probably could have just spun it in a vice, but I really didn't want to snap it off, or strip the threads in the carb body. so, that carb just needs to finished getting cleaned and put back on and we'll see how this motor runs with the correct carb. I was going to run it again tomorrow to go fishing, but I have another trolling motor on the boat already to go, so - I'll take my time and do it correctly, reminding myself I bungled the carb trying to do things too hurried in the first place ...
 

film495

Petty Officer 1st Class
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Apr 8, 2009
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ran this motor good. probably 4 -6 hours of mixed running over 2 or 3 days. Seems to run great. Think at some RPMs I'm rining the flywheel like a bell. I'll probably mess around with it Wednesday, next time I run it. Think I'll just put tape on the flywheel to see if it changes the harmonics. I kind of figure I'm just ringing it at certain RPM ranges, and that seems like a decent way to try to confirm the theory before I pull the flywheel and try to align things again.

I ran a 3hp Evinrude last week, and in a similar throttle position, I got the same harmonic dog ear high pitch chirping, but it was much harder to recognize, not as loud, but same exact sound. Maybe I need to do a bit of a fix on that one too soon.
 

film495

Petty Officer 1st Class
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Apr 8, 2009
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285
been runing this motor trolling. haven't had the flywheel off again to check and reset the coil position and to look in at the ignition to see if I have a wear spot from rubbing. runs good starts easy, high speed run strong for extended periods, I just avoid the mid range where it chirps a bit, which I'm convinced you're right it is coils rubbing. I heard my Evinrude 68, make the same noise, not as pronounced, but the same high pitched tone at a similar RPM, chirp. For trolling I think I need a hotter plug, doesn't like to troll down below 2.5 mph. It will, but it starts to miss after a bit, and sounds like it might stall out. I think it is the standard Champion J6C plug I'm running. Max speed on my GPS spedometer is about 5mph, thought it might hit 6, but I don't want to troll that fast anyway. Just backed off full throttle, it settles into about 4 mph, which is a fast troll, but I've had most of my success, up at 3 or 4 mph, and not down at 1.8 -2.5, which seems to be more common, but I learned it by trial and error, and never used a speedometer before to really know how fast I'm trolling.

ran this at least 10-15 hours trolling over the last couple weeks.
 

film495

Petty Officer 1st Class
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Apr 8, 2009
Messages
285
tried to run this motor yesterday, and it started first pull after sitting for a week, and it started fine like normal, but when I tried to start pushing the choke in it did not rev up, and after about 10 seconds it stalled. It seemed flooded, so - I ended up pulling the plugs and disconnecting the tank, and just cranking it out, a lot, and then letting it sit for a half hour, and put new plugs in it and it started for about 3 seconds and stalled. The new plugs did not seem wet, and upon closer inspection, the carb was readily leaking gas from the top right little hole, every time I pulled the engine over. Strange, the same motor went from severely flooded to no gas. All I can think of is stuck or sticking float assembly. If I squeezed the bulb, gas would come out the same hole, so - what is that float stuck and needle not seating at all? I tried tapping it a bunch with my socket, to no avail. It still confuses me that at first it was just flooded, wet plugs, gas shooting out the cylinders when I pulled it over, like the crank was just filled with gas. Then after I let it sit for a long while, the new plugs barely smelled of gas at all, and gas was coming out the front of the carb, and apparently not going into the crank, but if the bowl is full, it would have to go into the crank, what would stop it?
 

cyclops222

Lieutenant
Joined
Mar 21, 2024
Messages
1,289
Cork float is soaking up gasoline. Buy NEW float . Been there. Some dissolved varnish may be on parts. But mine worked perfectly when replaced.
 
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