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So I have built many engines before so I am not new to engine building. I am new to the VR6 motor though. We bought my son a 2001 Jetta with a VR6 in it that had a bad timing chain. So after taking it apart to replace the chain and take the head off to fix the bent valves I figured I am almost all the way there to pulling the motor out I might as well freshen up the bottom end. I replace all the main and rod bearings and honed the cylinders Then gapped the rings BUT when I put the new rings on the pistons and installed all 6 pistons the rotating assembly is REALLY hard to spin over with a socket and long ratchet. I just built an LS for my boat and its not this hard to turn over. I am wondering is this normal for the VR6 after break in will it loosen up? I had the machine shop measure and order the rings I needed so I don't think I got the wrong one. I am almost ready to buy a new set and pull all my pistons out and start over again. Any help would be appreciated. 

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You are right to be wary - if you can't turn it by hand, the starter isn't going to turn it over (when its all back together) either.

I would expect you should be able to turn the crank using a small ratchet.

 

Can you undo the big end caps for each piston and see if the crankshaft rotates freely on its own - without the pistons?

Then re-add a piston at a time to see how it affects the "turning load"?


You could have the wrong size bearing shells and when torqueing the bearing caps they could now be pinching?

 

Maybe your machine shop could better direct you...

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I checked the main crank bearings and the rod bearings they all check out fine and spin free. I am figuring that it has to be the rings. BUT could it be a bad (rough) hone job that the rings will seat into? Or rings that are putting to much pressure on the cylinder walls or ?????? 

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Sounds like you are right about the rings.

 

Last engine I rebuilt, the rings were too long once they were fitted to the piston and then compressed (to slide into the cylinder).

We had to trim the rings down to the correct length to allow for the correct gap when placed inside the cylinder.

 

That could be where all your resistance is coming from...

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