2000 Yamaha 3MSHY Flywheel won't turn

[mrlnavykorea]

This is the same engine that had the frozen carburetor. After a real struggle I got that to work, cleaned and replaced the parts with those from a Yamaha repair kit and replaced the reed valve. All that seems fine.
I unfortunately didn't think to turn over the engine before I started to repair the carburetor. After I reinstalled the carburetor I discovered that I could not pull the starter cord. I removed the manual starter and determined that that is OK. rewinds fine-no obvious problem. The flywheel won't turn at all. If I engage the transmission and turn the propeller I hear a periodic click which seems to me that maybe the piston is moving. Not sure of this, but clearly pulling the flywheel without the proper tools is beyond what I can do. I don't think you can use penetrants to try and loosen the flywheel because those would affect the electrical components in the stator. How much force can you apply to try to rotate the flywheel? Further disassembling the power head is also a major job. I have both the Clymer and Seloc manuals if that helps.

[DennisG01]

Are you trying to spin it with the spark plug in or out?

If you already have the plug out, try some gentle blows on the flywheel - maybe it will loosen up sticking piston rings.

[mrlnavykorea]

My lack of experience shows-Had the plug in.

[DennisG01]

Are you now able to get it to turn (loosen up) with the plug out?

[99yam40]

motor that will not move can be a major problem.
crankshaft, bearings, along with cylinders, piston rings all can rust and be destroyed.
sounds like your motor went underwater or was not stored properly for a long period of time

best to take it apart and see what all is a problem

[cpostis]

Look at this video, may get some idea of what you want to do.
https://www.youtube.com/watch?v=uJeAv3hGpxk

[mrlnavykorea]

I'm on Nantucket Island and the I only have a 5/8 spark plug socket. pause until can solve the logistics to obtain a 13/16 spark plug socket. The largest long mm socket I have is 19mm so that wouldn't work either.

[99yam40]

sounds like no tools and nothing that can be done to take it apart to see what is wrong

[cpostis]

I'm on Nantucket Island and the I only have a 5/8 spark plug socket. pause until can solve the logistics to obtain a 13/16 spark plug socket. The largest long mm socket I have is 19mm so that wouldn't work either.

About a 30 mile ferry ride one way off the mainland, I guess your tools are not on the island? Can you borrow from someone?

[TownsendsFJR1300]

Look at this video, may get some idea of what you want to do.
https://www.youtube.com/watch?v=uJeAv3hGpxk

Excellent video, especially for someone with limited tools.

Of course a full engine break down would be best (and much more expensive and time consuming). This little engine probably wouldn't be worth paying someone to repair.

As a side note, when the ATF that came out (after soaking) was on the floor, did it appear to be a very "rusty color"?

[DennisG01]

Based on your forum name... are you former Navy? First, and most importantly, THANK YOU for your service. Secondly... are you telling me a Navy man is unprepared with the proper tools?

[mrlnavykorea]

***, sensitive spot about a Navy man not being prepared. Some time ago I had a boat which was equipped with a small Japanese diesel. This motor was a piece of industrial jewelry and required a lot of work to keep it running properly. Went to a three day school just to learn to keep it running. As a result I have a pretty complete set of metric tools, except remember, no spark plugs.

At present I have a Maritime skiff with a 90 horse 4 cycle Yamaha motor which is maintained by the local dealer who is btw excellent. After this experience I appreciate how well he does to service the big engine every boating season

This little motor was barely used on a dinghy and was just left without being serviced for storage (Another sin against Navy doctrine-not my fault though), and now I want to use it on a small Zodiac. Took it to the dealer and his first estimate was $500 and up from there. Motor isn't worth that much so I thought it would be a decent tinkering project. Worked my way through the carburetor with the help of the manuals, which was a little frustrating. As to the question about the color of the ATF after soaking. No, it was not rusty. I think it was just a matter of time to get some penetrating agent into the area that was bound up.

The physical scale of the carburetor I can handle. Contemplating removing the flywheel (which does require specialized tools) and then breaking down the power head is overwhelming to me. As someone noted I served in Korea. I was an officer on a destroyer for 3 and 1/2 years. If you do the math I'm no kid (86).This is better than doing crosswords to keep mentally alert.

The local parts supplier doesn't have either the plug or the correct socket for the plug. I have to go off island for a few days and I will pick up the necessary sockets and miscellaneous pieces and when I return I will get the spark plug out. Then I will put some carburetor cleaner and then some blaster penetrator into the cylinder and see if it loosens up.
One last question- I assume that the numbers on the bolt heads are Newton meter torque values.

This forum is priceless, and I certainly appreciate everyone's time and effort.

[mrlnavykorea]

A quick update. I just watched the recommended video about un-seizing the engine. Went to look to see whether I had the correct socket and breaker bar. Took the tool to the flywheel and barely touched it and it came loose! Almost no pressure at all. I can turn it by hand with or without the transmission engaged. So now I will go off island to get a new plug and socket . I will remove the plug and use some two stroke oil in the cylinder. Then reassemble the whole thing and give it a try. Stay tuned! Again, this forum is priceless!

[DennisG01]

EXCELLENT! So it was likely just a stuck ring. I even had one stick on my engine over the Winter, even though I am adamant about winterizing and fogging. First time ever this happened, though. In my case, once I removed the plugs, the engine starter was able to spin it up. In your case, you just needed a little more leverage - although maybe with the plug out, you would have been able to do it with the rope, as well.

Either way, I'm glad you got that figr'd out! And I hope you know I was only razzing you a bit about the tools/unprepared I was NOT razzing about the first thing I said, though. You, and guys like you, are the reason we have things like this forum.

[TownsendsFJR1300]

Sounds like excellent progress.

IF you have ANY deep sockets, they'll work (correct size of course) for pulling the plugs. In a pinch, there should be enough room to put an adjustable wrench on them. Their not super tight..

AND, as posted above, THANK YOU FOR YOUR SERVICE!! .