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Remove crank bolt w/o turning crank
I'm replacing the timing chain and gears on the motor and while the job is pretty easy and straight forward, I need some advice on getting around an obstacle. Long story short, how do I remove the crankshaft bolt (harmonic balancer bolt) without turning the crankshaft? I need to slide the crank sprocket off and I can't with the bolt on there. But if I try to remove the bolt, naturally it turns the engine a bit and I need the cam and crank lined up at TDC so it cannot move it all.

Is this possible without using an impact wrench?
I usually put 2 of the crankshaft pulley bolts back in about half way and wedge a wrench between them in such a way that it catches the water pump housing or something else while turning.

Dave from PA
1972 Mach 1

I have a giant screwdriver-looking pry bar I use if not using an impact wrench. Install 2 bolts as was suggested and put your pry bar in between these. Don't take the chain and cam sproket off until you get the balancer off. You're going to have a similar issue when you use the puller to remove the balancer. once you have the balancer off, rotate the crank (using the balancer partially installed) and get the timing marks lined up before taking the chain and sprockets off.
To break the bolt free, put the socket on with a long breaker bar or ratchet. Let the breaker bar end touch the ground. then bump the key. The bolt will break free as the motor turns. Its a little sketchy but it works. Just did this on my nephews 74 mustang II. Couldn't get the impact in there with the rad in.


1971 Mach 1
408C Stroker
C4 w/3,000 stall
8.8" Rear w/3.73's
Disc brakes all way around.

[Image: 28ivsix.png]

you can also use a piston stop that threads into the spark plug hole, some people also take rope and feed it into the piston cylinder through the spark plug hole, fill up the cavity and leave the rope out the plug hole then turn the engine by hand and lock it up.
I might end up trying each of these tactics tomorrow depending on what tools I'll have available. The problem is that everything is stripped down to the timing gears and so I can line up the marks and when I go to loosen the crank bolt to get the sprocket off, the crank gets turned a bit and throws off my marks. Since everything is stripped down I don't have anything but to pry against. I kinda screwed myself on this one. Very frustrating.
Is your car manual or auto? If manual, put the transmission in 4th gear and e-brake on for extra insurance. That will prevent it from turning. Works every time for me. If auto, you can try leaving it in gear. Just not sure if it will work.

The rope trick works good. Assuming compressed air isn't available you can also look into renting an electric impact gun or buying one from harbor freight.

73 conv. 460, D0VE large valve heads, Performer RPM manifold, Voodoo 227/233 cam, Holley 950 HP carb, C6 trans, 3.25 trak-loc.
Jam a screwdriver in between the timing chain and gear on the left side to lock the crank then remove the bolt.
It's okay if you move the gear while trying to remove the bolt. Even with the bolt out you there is a key on the crank that makes sure the balancer is in the correct orientation. So you can adjust it back to TDC without the bolt in.

73 Convertible - 351C/4V CC heads/4bolt/forged flat tops/comp 270/rhodes/mallory unilite/tri-power/hookers/glasspacks/c6/3.50 limited slip/Gear Vendors/Global West sub frames, strut rods and shelby style traction bars/ Rear sway bar/tilt steering (not original)

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