Crankshaft bolt on 02 Accent
 

I can not seem to break the crankshaft bolt loose on my 2002 Hyundai Accent...tried impact wrench (3/8 hose about 150 lbs pressure and nothing) then tried breaker bar and engine wanted to turn any suggestions besides the old starter breaker bar trick
Is there a way to hold crakshaft pulley and use breaker bar on bolt? with out damage to pulley? Or do I need bigger impact?
Also can I lock the timing gears in place so I can timing belt on right?
One other question can water pump be changed with timing still on?
THANKS