How to turn engine over 90 degrees?

st0n3

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Jun 24, 2012
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I know this is an old thread, but it is still very helpful for those learning how to align the engine.

Turn the engine over 90 degrees and check again.

Keep turning engine over in 90 deg. increments. This ensures that your coupler is centered and true.

Probably a dumb, beginner question, but how exactly do you "turn the engine over 90 degrees" when aligning the engine with the alignment bar? Does this mean that the coupler attached to the engine actually rotates 90 degrees?

Thanks in advance for any help.
 

tpenfield

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Jul 18, 2011
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In a word . . . yes.

You will need to attach a breaker bar to the crankshaft pulley on the front of the engine. There are special adapters to attach to the crankshaft pulley.
 

GA_Boater

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And take out all the spark plugs to make it easier to turn.

Welcome aboard..........................Finally. :smile:
 

Rick Stephens

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Or just put a mark on the harmonic balancer and tap your starter switch. Do not turn motor by putting a socket on the crankshaft nose bolt in the harmonic balancer. Guaranteed to strip out the threads. You can also grab and pull the motor using the alternator belt on same engines.
 

gm280

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Or just put a mark on the harmonic balancer and tap your starter switch. Do not turn motor by putting a socket on the crankshaft nose bolt in the harmonic balancer. Guaranteed to strip out the threads. You can also grab and pull the motor using the alternator belt on same engines.

Not sure how you could strip the threads using a socket on the harmonic balancer bolt to turn the engine? I've done it more times then I can count and never had an issue...ever. In fact I use that bolt to degree engines when installing new cams. :noidea:
 

Rick Stephens

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Not sure how you could strip the threads using a socket on the harmonic balancer bolt to turn the engine? I've done it more times then I can count and never had an issue...ever. In fact I use that bolt to degree engines when installing new cams. :noidea:

You're a very lucky man then. Might get you to buy me a lottery ticket. Too easy to over tighten and strip those out. Have seen it happen.
 

gm280

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You're a very lucky man then. Might get you to buy me a lottery ticket. Too easy to over tighten and strip those out. Have seen it happen.

You do realize that when building some engines, their shop manuals tell you to use that bolt to verify the torque needed to turn the engine to verify it is assembled correctly don't you? If it is too tight you did something wrong. The same if it isn't tight enough too. And how do you degree a cam any other way?
 

harringtondav

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May 26, 2018
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...I think if the spark plugs are removed, the torque on the crankshaft bolts is safely low. If the engine has puller holes on the balancer, I attach my puller and bar the engine over with a pry bar or large screwdriver wedged on the puller bolts. Sometimes just cranking on the puller jack screw will turn the engine along with the puller body.
 

Rick Stephens

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You do realize that when building some engines, their shop manuals tell you to use that bolt to verify the torque needed to turn the engine to verify it is assembled correctly don't you? If it is too tight you did something wrong. The same if it isn't tight enough too. And how do you degree a cam any other way?

Without plugs. Without a drive attached. Without all the accessories. Sure.
 
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