Best technique/tool for manually turning crankshaft
Thread Starter
Race Director
Joined: Dec 2000
Posts: 17,786
Likes: 5
From: Florida
Best technique/tool for manually turning crankshaft
I just gathered all of the parts that I need to swap my valve springs, replace all seals and rebuild the rocker arms using the Comp Cams trunion kit (my Christmas vacation project). Car is an '02 Z06 with 53K miles (it's my daily driver).
I have also read ALL of the threads on performing this R&R. I plan to used compressed air to hold up the valves, but I will need to rotate the crank a few times when I torque the rocker arms (please don't argue whether this is required or not...I'm sticking to the factory recommendations here and using all factory parts - except the trunion rebuild kit).
I have heard that a strap wrench works best, and possibly using one with an old accessory belt. Best from up top through the passenger's side, or from the bottom? I can't see any way to get a socket/wrench on the balance bolt (oil cooler in way and I'd rather not move stuff that I don't otherwise need to).
Thank you in advance for the advice.
-Dean
I have also read ALL of the threads on performing this R&R. I plan to used compressed air to hold up the valves, but I will need to rotate the crank a few times when I torque the rocker arms (please don't argue whether this is required or not...I'm sticking to the factory recommendations here and using all factory parts - except the trunion rebuild kit).
I have heard that a strap wrench works best, and possibly using one with an old accessory belt. Best from up top through the passenger's side, or from the bottom? I can't see any way to get a socket/wrench on the balance bolt (oil cooler in way and I'd rather not move stuff that I don't otherwise need to).
Thank you in advance for the advice.
-Dean
Le Mans Master
Joined: May 2007
Posts: 5,393
Likes: 17
From: Belleville Mich.
15/16" off set box end wrench, 15" long. (worked for me)
Standing on the pass & you can reach the crank bolt easily.
Once you mark the pully , when #1piston is @ tdc, you will be able to know where the cylinders are when rotating to do the complete job. (with out air)
Good luck.
Standing on the pass & you can reach the crank bolt easily.
Once you mark the pully , when #1piston is @ tdc, you will be able to know where the cylinders are when rotating to do the complete job. (with out air)
Good luck.
Last edited by bumble-z; Dec 12, 2011 at 10:11 AM.
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
Since your using compressed air to hold the valves up just remove all the plugs first.
Your going to do that anyway when you attach air to each cylinder it will push the piston to BDC at this point both valves will closed anyway.
Just replace and torque the rockers as you go on.
We don't need no stinking special tools!
Reinstall the plugs last!
Your going to do that anyway when you attach air to each cylinder it will push the piston to BDC at this point both valves will closed anyway.
Just replace and torque the rockers as you go on.
We don't need no stinking special tools!
Reinstall the plugs last!
Team Owner
Joined: May 2001
Posts: 87,381
Likes: 1,593
From: Western NY
Since your using compressed air to hold the valves up just remove all the plugs first.
Your going to do that anyway when you attach air to each cylinder it will push the piston to BDC at this point both valves will closed anyway.
Just replace and torque the rockers as you go on.
We don't need no stinking special tools!
Reinstall the plugs last!
Your going to do that anyway when you attach air to each cylinder it will push the piston to BDC at this point both valves will closed anyway.
Just replace and torque the rockers as you go on.
We don't need no stinking special tools!
Reinstall the plugs last!
Beat me to it!!
Thread Starter
Race Director
Joined: Dec 2000
Posts: 17,786
Likes: 5
From: Florida
bumble-z, thanks for the tool reference. That is what I wanted to know.
Bob/leadfoot, I have done cam swaps on early gen SBs so I know some of the other tricks (i.e. removing all plugs, etc.). Not sure what you mean by stating that air pressure will push the piston to BDC. ?!?!? Have another beer! LOL
Bob/leadfoot, I have done cam swaps on early gen SBs so I know some of the other tricks (i.e. removing all plugs, etc.). Not sure what you mean by stating that air pressure will push the piston to BDC. ?!?!? Have another beer! LOL
Le Mans Master
Joined: Nov 2005
Posts: 6,993
Likes: 25
bumble-z, thanks for the tool reference. That is what I wanted to know.
Bob/leadfoot, I have done cam swaps on early gen SBs so I know some of the other tricks (i.e. removing all plugs, etc.). Not sure what you mean by stating that air pressure will push the piston to BDC. ?!?!? Have another beer! LOL
Bob/leadfoot, I have done cam swaps on early gen SBs so I know some of the other tricks (i.e. removing all plugs, etc.). Not sure what you mean by stating that air pressure will push the piston to BDC. ?!?!? Have another beer! LOL
Team Owner
Joined: May 2001
Posts: 87,381
Likes: 1,593
From: Western NY
Absolutely!!!
With all the plugs out, there's no compression whatsoever, to hold the crank in any one position. Fill one hole with compressed air, and what happens? The compressed air drives that piston down, and holds the valves closed. (Naturally, you have to keep the source of air hooked to the cylinder head....)
Thread Starter
Race Director
Joined: Dec 2000
Posts: 17,786
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From: Florida
You guys would be talking about some serious air pressure to move an internal reciprocating mass (with some piston/bearing friction and the natural resistance of lifters/pushrods/rockers/springs) that much. 
I plan to keep spring pressure (resistance) at a maximum, as I will R&R each cylinder one by one, then torque the rocker arms, then reinstall fresh plugs, etc., etc.
Thanks again for the inputs!
I plan to keep spring pressure (resistance) at a maximum, as I will R&R each cylinder one by one, then torque the rocker arms, then reinstall fresh plugs, etc., etc.
Thanks again for the inputs!
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Team Owner
Joined: May 2001
Posts: 87,381
Likes: 1,593
From: Western NY
Not at all!!
I had my regulator set to 85-90 lbs, when I did the valve springs and seals on my LT1 Camaro....
Le Mans Master
Joined: Nov 2005
Posts: 6,993
Likes: 25
You guys would be talking about some serious air pressure to move an internal reciprocating mass (with some piston/bearing friction and the natural resistance of lifters/pushrods/rockers/springs) that much.
I plan to keep spring pressure (resistance) at a maximum, as I will R&R each cylinder one by one, then torque the rocker arms, then reinstall fresh plugs, etc., etc.
Thanks again for the inputs!
I plan to keep spring pressure (resistance) at a maximum, as I will R&R each cylinder one by one, then torque the rocker arms, then reinstall fresh plugs, etc., etc.
Thanks again for the inputs!
Thread Starter
Race Director
Joined: Dec 2000
Posts: 17,786
Likes: 5
From: Florida
Again,
to everyone for their inputs.-Dean
Racer
Joined: Dec 2005
Posts: 287
Likes: 2
From: Bay Area California
I will take your word on it AND keep the tranny in gear during the valve spring portion of this R&R. I can see where enough air pressure could push a piston to the bottom of a bore (and the shorter end of the connecting rod throw). But with 16 pushrods applying pressure to 16 rockers/springs, I just figured that was enough "opposing force" to keep the entire reciprocating assembly from rotating at all. Then again, the last engine I did this on had solid lifters, too.
Again, to everyone for their inputs.
-Dean
Again,
to everyone for their inputs.-Dean
A1
Cruising
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