LT5 Assembly Project

[LGAFF]

Well maybe there is more to the motors history that I have been told....might need to take it to the machine shop

[carter200]

Originally Posted by LGAFF

No line bore as no known history of a spun bearing, etc

I always line bore as a precaution. Something is NOT straight if the bearings were coated correctly. Good luck....

[tomtom72]

Okay, I'm not sure if what I'm about to say makes any sense or will help you Lee. I have a set of OE size main bearings, you want me to send them to you to check against what you have going on now with your stuff?

I bought these from Kurt a long time ago when he had some sets made up.


Tom

[LGAFF]

Thanks for the offer, but I am guessing I will be taking it to the machine shop to make sure I find and address the issue properly.

[cvette98pacecar]

Originally Posted by tccrab

I would love to see pics of the entire process, especially the removing and replacing the heads and timing the camshafts.
Post 'em up!!
You can be sure that I will download and save every one of them for future reference.

TomC
"Crabs"

That makes 2 of us.

[lbszr]

Originally Posted by LGAFF

Well maybe there is more to the motors history that I have been told....might need to take it to the machine shop

Were the crankcase bolts along the side and rear torqued, as well as the main bearing bolts when the crank was locked?

Did the main bearings plastigage ok?

[LGAFF]

I did not get as far as to do he bolts on the out edge, once I did the main and everything stopped turning, I stopped.

I did not gauge it, honestly as they were used bearings, did not expect a clearance issue.

[lbszr]

Originally Posted by LGAFF

I did not get as far as to do he bolts on the out edge, once I did the main and everything stopped turning, I stopped.

I did not gauge it, honestly as they were used bearings, did not expect a clearance issue.

The manual does have an important message, do not attempt to rotate the crank until the outer crankcase bolts are tight. I don't know if it would be enough to lock the crank, but I think it could chafe the bearings.

I plastigaged mine without tightening the outer crankcase bolts. The plastigage might show a taper if there's a block or crank problem.

[LGAFF]

I will go back today, do them all and the outside to see if that does it...I would think the out bolts would be part of the torque sequence if they were that important......will try it, thanks

[A26B]

Lee,

I would suggest that you install the bearings in the upper crankcase, lube the bearings and lay the crank in place. Set up a dial indicator on the center journal & rotate the crank to check for run out.. Repeat for each end journal. This is not the ideal method, but is a good place to start.

Then, after the crank has been checked, install the bearings only and assemble the lower crankcase. Using telescope gauges, measure each main bearing i.d. in 2 different locations, avoiding the split line. Then mic each crank journal. Use the same mic to measure the telescope gauge as you use on the crank. The actual dimension is not as critical as the differential measurements on each journal, i.e. clearance.

I am assuming that you have inspected the bearing bores in the block & girdle to insure there is no damage that might prevent a bearing shell from seating properly.