Starflite 3 75hp starter issues

[wdirnbeck]

I’m having some troubles with my Non running starflite 3 with electric start. When I test the starter off the engine with 12 volts from a marine battery it spins fine and is also able to engage the bendix. However when I have the starter mounted on the engine using the boat’s ignition system (unicharger) or jumping the starter from a battery directly the flywheel will only rotate a few degrees. Then it will stop. When I rotate the crank with a breaker bar I do notice it takes some effort when it gets to a certain point then is easy to keep rotating after that. Any ideas if this friction is stopping the starter and what it could be?

 

[racerone]

Remove the sparkplugs.----Does the engine now turn easily by hand ?-----And remove lower unit as it might be the issue.

 

[tphoyt]

You should be able to rotate the flywheel by hand. Sounds like something is wrong internally to me. When is the last time this motor ran?

 

[wdirnbeck]

You should be able to rotate the flywheel by hand. Sounds like something is wrong internally to me. When is the last time this motor ran?

You would have to ask the mice living inside it… the person who sold it to me couldn’t give me an answer as he “knew nothing about it” but going off the most recent registration it looks like it could’ve been 30 years since it was last moving. I don’t know if this would be indicative of anything but it seems like the point where it gets hard to rotate is when the flywheel timing mark is around the 4 o’ clock position. There’s no scraping or jagged halts when I attempt to rotate it, but it just takes more force even with all the spark plugs out. When I first got the thing it would not rotate at all but a concoction of oils seemed to do the trick to get it at least able to move

 

[racerone]

Time to inspect.-------Remove the 4 bypass covers on the side block.----Have a look in and see what is in there.

 

[jimmbo]

As suggested, drop the lower unit, and see if it still binds up. With the Spark Plugs out, can you see the tops of the Pistons?

 

[wdirnbeck]

As suggested, drop the lower unit, and see if it still binds up. With the Spark Plugs out, can you see the tops of the Pistons?

Yes, my endoscope camera thing was too large to get inside the cylinders but from what I could see, each piston looked fine albeit with some mystery buildup on top that didn’t really look that concerning. Couldn’t get camera around enough to see the cylinder walls though. I’ll try and get the lower unit off as well as those bypass covers

 

[jimmbo]

I was wondering if you were serious about Rodents stockpiling stuff in the Cylinders, as it could interfere with the Pistons from gettin to TDC, If the engine had been stored other than Vertical, and even then, Rodents could have gotten that far in there

 

[wdirnbeck]

I was wondering if you were serious about Rodents stockpiling stuff in the Cylinders, as it could interfere with the Pistons from gettin to TDC, If the engine had been stored other than Vertical, and even then, Rodents could have gotten that far in there

This sounds like a possibility. Maybe there’s some buildup I can’t see

 

[jimmbo]

Without a History on the Motor, anything is possible. If the Engine had been under water, and was running when that happened, Things like Connecting Rods, can and do bend, and will result in an Motor that can stiffen up when rotated. Also Cylinder Walls and Rings could rust, and close up Tolerances making for binding. You could try some Penetrating Oil in the spark Plug holes, myself, I prefer to use Engine Tuner, but that is my choice.
Of course the Problem, if in the Powerhead could be the Crankshaft and/or the Connecting Rod Bearing, including the Bearings in the Piston Pin

 

[wdirnbeck]

Without a History on the Motor, anything is possible. If the Engine had been under water, and was running when that happened, Things like Connecting Rods, can and do bend, and will result in an Motor that can stiffen up when rotated. Also Cylinder Walls and Rings could rust, and close up Tolerances making for binding. You could try some Penetrating Oil in the spark Plug holes, myself, I prefer to use Engine Tuner, but that is my choice.
Of course the Problem, if in the Powerhead could be the Crankshaft and/or the Connecting Rod Bearing, including the Bearings in the Piston Pin

I’m new to outboards, and I’m starting off with what seems like ancient tech. Would it be wise to take off the lower unit to rule out any issues with the gearing even if the prop spins freely in both directions and it is in neutral?

 

[jimmbo]

The propshaft is not engaged to either the Forward or Reverse Gear when it is in Neutral, so it can spin freely. Removing the Lower unit from the motor takes the Forward, Reverse Gears, and the Pinion out of the Equation. Once it is off try rotating the Flywheel, if the Motor now turns freely the Problem is in the Lower unit. If the Engine is still binding, then further investigation is need there

 

[tphoyt]

May as well. You will need to do a water pump service at some point anyway if you decide to move forward with any other problems.

 

[ct1762@gmail.com]

you need to replace the head gaskets anyway, so i'd pop the heads off and have a look. if you do not replace the head gaskets, those graham cracker like gaskets will leak sooner or later.

 

[jimmbo]

60 year old motors do have some secrets

 

[jimmbo]

This might help

http://www.fiberglassics.com/library/images/9/98/Evinrudeservice004.pdf

 

[wdirnbeck]

60 year old motors do have some secrets

Pulled the lower unit off today and am still having a problem with the it being hard to turn over. I also went ahead and pulled the heads and am happy to see the cylinder walls look like they’re in pretty good condition and there isn’t any sort of blockage. Took some measurements of the top of each piston at TDC to the very top of the cylinder walls to see if there was any variance and they all seem to be the same. Going to see what I can see from the bypass ports and whatever this cover is that is in front of the thermostat. I’m not expecting to be able to tell immediately what’s wrong and I don’t have any sort of hoist or stand to separate the block so I’ll have to devise some experiments to find my issue if I can even get a look at the crankshaft. See my attachments for the pretty pistons

 

[racerone]

???-----Those cylinders are NOT IN GOOD CONDITION in my opinion.-----If you want a nice runner it has to come apart !!

 

[wdirnbeck]

???-----Those cylinders are NOT IN GOOD CONDITION in my opinion.-----If you want a nice runner it has to come apart !!

Good enough to run at all? Haha. It’s looking like that’s how this is going to go down anyways.

 

[tphoyt]

I agree it’s iffy at best. Its hard to tell from the pics but there looks to be zero crosshatching left. Even if the scoring it has it light there is so much of it there will be opportunity for compression loss.
That carbon build is likely the cause. It can be fairly abrasive stuff. Have you had a chance to inspect the rings yet?