Help?
Thread Starter
On The Tree
Joined: Aug 2006
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Help? Got a question but not sure where to go to ask so here we go. we have a 97 4.3 motor out of a gmc pick up, stupid us we did not mark the rods when we dropped them out of the motor, no big deal we thought, now that we are putting them back in we get them in torque them down to about twenty pounds or so and the crank will not turn over locked tight. we know its not the crank, we thought it might be at first so we got another one, now question is this, theses rods have gma and gmb stamped on them is there a certain order they have to go in or do you think that since they use heat to put the piston back on the rods they warped the rods. 
Last edited by Nemo02Z; Aug 27, 2006 at 07:57 PM.
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Joined: Dec 2004
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From: K-W, Ontario
I bet you have the non chamfered side of the rod backwards and it's binding
on the crank.
Look at the big end of the rod and you'll see one side is machined. The chamfered
side goes against the counter weight.
on the crank.
Look at the big end of the rod and you'll see one side is machined. The chamfered
side goes against the counter weight.
TECH Resident
Joined: Dec 2004
Posts: 845
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From: K-W, Ontario
Not unless the cap is installed with the chamfered side reversed (which would
be easy to see).
Have you installed new bearings and clearanced the bottom end? Did you have
the connecting rods checked and machined as necessary before installing them?
be easy to see).
Have you installed new bearings and clearanced the bottom end? Did you have
the connecting rods checked and machined as necessary before installing them?
Thread Starter
On The Tree
Joined: Aug 2006
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Yep most parts are new the block just came back from the shop so clearances are good, for the most part we know it has to do with the rods and since nothing was labled we are gonna have to go at it by trial and error, and keep switching rods and caps. which with the info you gave me it will be easier. thanks
Thread Starter
On The Tree
Joined: Aug 2006
Posts: 172
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Originally Posted by Adrenaline_Z
I bet you have the non chamfered side of the rod backwards and it's binding
on the crank.
Look at the big end of the rod and you'll see one side is machined. The chamfered
side goes against the counter weight.
on the crank.
Look at the big end of the rod and you'll see one side is machined. The chamfered
side goes against the counter weight.
Thanks again
