The bolt is normal right hand thread.
A screwdriver will never do it. Think 18" breaker bar with a 2' pipe on it.

To counter-hold the crank, I recommend the Rope Trick. My canned post follows...

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Although I own both counterhold tools for the B230 and B21/23, I no longer use either one. Instead, I prefer a piece of cotton clothesline (nylon or similar is OK too), for what is called "The Rope Trick". It's quicker and easier than the "tool", and the basic steps are simple:


1 - Pull plugs and rotate crank to #1 0° TDC Compression
2 - Look thru oil fill hole to verify #1 and #2 valves closed, The #1 cam should be pointed inboard and up about 45°, with #2 pointed horizontally outboard.
3 - Rotate crank about 90° past TDC.
4 - Stuff about 30"of clothesline into # 1 plug hole, leaving 6" outside (feeding the rope in thru a short length of heater hose makes the job even quicker).
5 - Rotate the crank backwards until the packed rope stops further rotation.
6 - Use socket, breaker bar, and pipe extension to loosen pulley bolt.
7 - Tighten bolt the same way, but start with crank about 90° before #1 TDC Comp.
8 - When tight to spec, back the crank up a little a little and remove clothesline.

To my knowledge, this is the only "trick" holding tool alternative that allows tightening the bolt to book spec of 44 lb ft, then an additional 60° (B230), or 122 ft lbs. for B21/23.

Here's what some first-time users had to say:

• "The "rope trick" for holding the engine still while removing the harmonic balancer bolt worked like a charm. Honestly, I doubted that it would, but WOW!"
• "I finally had an opportunity today to use one of the "rope" tricks to help take off the crank bolt. All I can say is - it worked like a charm! Two seconds and I had the crank bolt off..."
* 5/29/05 "I did this a few weeks ago exactly as ... described and it couldn't have been easier."
• 12/28/05"....the rope trick worked like a charm to loosen and tighten the crank pulley bolt!!,"
• 1-10-06 "tryed the . . . method without any luck but the rope trick worked fine to remove the pully bolt"
• 6-26-06 "(thanks for the rope trick! Worked like a charm.)"
• "i just completed the task using the rope trick and my opinion is that it is extremely gentle as compared to jamming a screw driver anywhere. it required about 5 to 6 ft. of 1/4 inch rope and made mission impossible mission simple."
• 4-25-07 at http://www.brickboard.com/RWD/index.htm?id=1178645.
• 7-7-08 at "Rope Trick Rocks".
• 7-20-08 "was amazed at how easily it worked" .
These just in, Jan, 2009:
• guillermo.
• sonoflee.
• N7SC
• 1-31-09
• 2-03-09

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Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.