Advice - How to remove crank nut?

[Oneofthegreats]

The only problem with doing it that way is you can snap off the keyway on the crank sprocket.

The keyway for the crankshaft pulley has nothing to do with it.

It's straight onto the crank bolt & driven by the starter.

[Preen59]

Yeah dude, i really don't see how that could happen. Well, it wouldn't happen. There's no way it can..

[ontarv]

use the bracker bar on the ground lots
always doing 90 model com's ( cause there balancers are crap )
the key is to flick key so even if it does fire you've already turn it off
and never put the bar where it hit anything breakable because the bar
can bounce back if its realy tight

[abreut]

I haven't actually seen it happen but I have seen crank sprockets that have had the keyway broken off. I think this probably happens if you run the motor with a loose crank bolt and it hammers at the keyway.

When I had a crank bolt that was ridiculously tight and the motor was out I was going to lock up the other side of the crank and just breaker bar off the nut. I was advised against that by a mechanic who said it could damage the keyway. I haven't seen that happen but maybe it puts undue stress on the keyway as well if the bolt is really seized against the sprocket it will be yanking on the sprocket and its keyway when it finally cracks and turns. Anyway I just made up a tool just like Pete did. Its the safest way to crack that bolt.

[Peter Jones]

That reminds me I meant to post the pic of that tool in this thread as well as the projects thread.

Even managed to put a bit of a bend in this one. I might weld a solid bar into the angle for next time. This angle is only 3mm - thicker would be better.

[abreut]

I used 1" pipe, fairly thick walled and it still bent a little! The crank bolt on mine was just so ridiculously seized I have never seen one like it. The proper factory tool is just one piece of flat bar - probably 5mm thick or so.