Impossible bolt? Engine damage if removed? (with pic)

[unclejemima]

I have a 2003 250EX (same engine as recon 250)

The Recon has a recoil starter, the 250EX does not. The 250EX has a blank plate where the recoil would go. Inside is a bolt that need to be removed for the recoil basket.

The bolt I'm trying remove is connected to the engine, so when ever I try loosen the bolt, the engine will just turn over.

I've tried putting it in 1st gear and reverse gear to lock the engine, but the engine will still spin so the gear has no effect.

Any idea how in heck I would get this bolt off?

Looks like there is a o-ring and another part attached this bolt (#9) (see pic below)

Perhaps I will damage something up by removing the bolt? It might not be as easy as just removing the bolt and re-installing it...? Will it damage the engine or loosen any parts that I can not get access without disassembling the engine? Any idea's?

Thanks

[32bit.flannel]

I'm no expert on the matter, but it sounds like that bolt/threading is how the recoil starter would spin the motor. If you want to get it off you'll need to stop the motor from spinning over. What I've done on my Small Block Chevy motors in the past is install a piston stop at Top Dead Center. First disconnect the battery so you don't do anything silly on accident. Then take out the spark plug and spin the motor around by hand until the piston is all the way at the top of the stroke. If you are _*careful*_ you could just use a bolt through the spark plug hole (assuming the plug angle in the combustion chamber allows contact with the piston), but it is best to get the proper tool for the job (piston stop - Google Search). The three most important things are:
1) Make sure not to lose any parts in the combustion chamber or you will be pulling the head off!
2) Be gentle because you do NOT want to put a niche in the piston, which could cause a hotspot and detonation/pre-ignition.
3) Don't trash the threads for your sparkplug!

How badly do you want to get this bolt out? lol.