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Offline jordan.stevens.9469

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Seized engine
« on: August 04, 2015, 03:32:05 PM »
Is the crankshaft bolt on the left side. (How can I get leverage on my crankshaft to un-seize the engine)
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Offline eigenvector

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Re: Seized engine
« Reply #1 on: August 04, 2015, 04:01:02 PM »
Do you know why it's seized?  I'd be asking that BEFORE trying to unseize it.
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Offline SOHC Digger

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Re: Seized engine
« Reply #2 on: August 04, 2015, 04:08:58 PM »
As you are seated on the bike, bolt on the left side behind the alternator cover.
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Offline Stev-o

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Re: Seized engine
« Reply #3 on: August 04, 2015, 04:38:29 PM »
Just to clarify, there is a differance between a "seized" engine and one that is "stuck".

Seized typically means a mechanical failure whereas a motor that has been sitting for a spell gets stuck, the rings rust to the cylinder walls.

Have you tried putting in gear and rocking it back and forth?
Some guys pour a "cocktail" of ATF/Acetone in the spark plug holes and let that penetrate a day or two and then try to break her free.
This has worked for me...
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Offline mystic_1

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Re: Seized engine
« Reply #4 on: August 05, 2015, 06:19:45 AM »
Might want to try a strap wrench around the alternator rotor itself, rather than trying it's mounting bolt.  You'll get more leverage that way.

The "nut" at the other end of the crankshaft (right side points cover) isn't really a nut at all but a nut-shaped fitting that's mounted to the ignition advancer shaft, which is only like 6mm or so.  Fine for indexing the motor during timing, but don't try to free a stuck motor with it or you'll snap it off.

mystic_1
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Offline BobbyR

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Re: Seized engine
« Reply #5 on: August 06, 2015, 12:22:26 PM »
Rocking it in gear exerts more force and prevents breaking something with a breaker bar.
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Offline jordan.stevens.9469

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Re: Seized engine
« Reply #6 on: August 06, 2015, 06:10:46 PM »
I have been rocking it back and forth for about a week now, I got it to move a bit and then as I kept moving it, it froze once more.  Now it will not budge. So I tried taking off the head, after getting the valve cover off I realized I can't get to one of the camshaft sprocket bolts because I can't get the engine to move. Where do I go now? I've heard "sacrifice the sprocket and get some leverage on that" but that just doesn't seem kosher to me. Where do I go from here?
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Offline jordan.stevens.9469

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Re: Seized engine
« Reply #7 on: August 06, 2015, 06:14:25 PM »
Let me know if you guys need pictures.
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Offline bear

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Re: Seized engine
« Reply #8 on: August 06, 2015, 07:14:06 PM »
I think I would be more inclined to stick it on the bench and remove the bottom case before I started cutting things up. ;)

Cheers,
Brian
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Offline rundogdave

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Re: Seized engine
« Reply #9 on: August 06, 2015, 09:03:52 PM »
I had the same issue a few weeks ago. Engine frozen up for an unknown reason. Rocking it didn't work. Cam sprocket bolts at the 12 and 6 o'clock position. I ground down a box wrench to get over the bolt head for the bolt at the 6 o'clock position. Didn't have to cut the cam chain.
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