All cleaned up, all the new parts are here and correct, we gotten the right gasket sealer...

Alrighty then, let's put this puppy back together!

• Using the driver shown at left, install the cam shaft bearings
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•  Install the cam timing gear on the cam shaft.  Don't forget the cam retainer ...

• Carefully set the the cam shaft aside -- we won't be installing it just yet ...

• Lots of folks have trouble getting their main seals to fully seat, resulting in a leaky engine.

• To improve installation of the rear main seal, try making a rear main seal seating tool  (called a "Herbison") from a Ford 302 V-8 piston as shown.  The Herbison's diameter exactly matches the inside radius of the Chevy Stovebolt (i.e., 216, 235 and 261) rear main bearing cap and journal.

• Carefully work the rope into place

• Double check that your main bearings actually match your engine ...

• Insert the main bearings.  Remember that each Main Bearing is unique to it's journal on the crankshaft so keep them in order.  Once installed, apply assembly lube to each one

Main bearings & seal installation

A "Herbison" vastly improves the quality of the rear main seal installation and will prevent people from mistaking your engine for a GMC or a Detroit ... :)

Crankshaft installation

• Most procedures involved with engine rebuilding are critical but probably none more so than a proper crankshaft installation.  After all, it's the focus of the whole system.

• Before you go any further, reinstall the road tube baffle plate.

• With the main bearings in place, carefully place the crankshaft in the block.  This is a two-person lift.  Be careful of fingers or clothing getting caught.

• Put the main bearing caps in place and tighten the bolts but do not torque to specs yet.

• Insert a 1/2-inch drive breaker bar into the front end of the crankshaft and gently rotate it.  Does it rotate easily without any tight spots?  If the crank has been properly ground and there were no issues with the journals in the block, then it *better* rotate freely!  If it does, proceed!  If not, start working backward through the mains to see where the problem is.

• If it freely rotates, then torque the mains to spec and repeat the rotation check.

• While we are here, lets go ahead and install the crankshaft timing gear on the front of the crankshaft as shown in the image at left.
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  • Be sure to firmly wedge a block of wood between the back of the crankshaft (where the flywheel attaches) and the engine stand to absorb the thrust applied from driving the gear on.
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  • If you've drilled the end of the crankshaft to accept the harmonic balancer retaining bolt, then you can use that to drive on the gear.  But either way -- be careful!  It is easy to destroy the crank at this point and you don't want to do that ...

• So far, so good.  Now, put your favorite music on the shop stereo and settle in --  this next step takes awhile and is very methodical ... we'll be checking clearances.  Start at either end of the crank and check the clearances of each main bearing one at a time.
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  • Remove the bearing cap and place a strip of plastigage on the crank journal longitudinally (see image at left -- unsquished part of the plastigage is from the oiling groove in the bearing)
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  • Torque the bearing cap bolts to spec (100-110 ft-lbs), then remove the cap to measure the plastigage.  On our rebuild, We reduced the torque specs slightly (about 10%) because the thread lube we used was anti-sieze compound instead of the recommended 30 weight motor oil. Better thread lube equates to less turning effort to get the necessary "stretch" on the fasteners.
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  • The ideal Plastigage measurement for a street-driven engine is around .0015", but that depends on how the crankshaft is ground. The machine shop that ground our crank does mainly race car engine work so the machinist used the "low side" of the tolerance on the rod and main bearing journals, resulting in about .001" extra clearance on all the bearings. It's pretty routine for race shops to add a little clearance to assure good oil flow, and use a high volume oil pump to keep plenty of oil flowing through the bearings. This adds some extra cooling effect, and also prevents the engine from tightening up when it's run hard at high RPM.  So this engine has .0025" clearance on the main bearings which should be no problem as we will be running 15W-40 oil from now on in this engine.
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• • Additionally, the 1960 Chevy shop manual states that acceptable clearances on the main bearings are  .003" max to .0005" min.  So we are good to go.

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  • If you have *less* than .001" clearance, you will need to shim the bearing.  Open the little brown envelope of shims that came with your gasket set.  Use your micrometer to find the ones you need.  Remember, you may not need to shim both sides of the bearing ...  Just repeat the plastigage process until you get the correct clearance.  No shims?  No problem -- see the image at left ...  Happy shimming!
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  • Once the bearing checks for proper clearance, clean off the plastigage, reapply assembly lube, replace the main cap and torque to spec.  If you can't get all the plastigage, no sweat -- it will quickly dissolve in the assembly lube/engine oil.
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• Once all the clearances are checked, shims (if needed) are in place and the caps are torqued ...  Congratulations!  You've installed the crankshaft!

• Reinstall the cleaned (or replaced) timing gear oiling nozzle on the cylinder block front end plate and, using a new gasket, reinstall the plate on the block.  Tighten the screws to 15-20 ft-lbs and stake securely at the bottom of the slot (i.e., use a small chisel to make a wedge in the metal of both the edge of the screw and the edge of the plate to keep the screw from loosening).

Plastigage is easy to use -- the wrapper provides the measurement.  Just match the width of the squished plastigage to a bar on the wrapper to determine the clearance.

Forgot the shims??  No problem!  Beer cans provide excellent shims and mostly are the same thickness and material as a shim ...  Win Win!  Check it with the micrometer, though.

Stovebolt.com advises against drinking beer while rebuilding your engine...  You can, however, drink beer while watching someone else rebuild your engine...

The crankshaft has been carefully placed in the block.  The main caps are in place but not fully torqued.  The timing gear has just been installed using the end bolt jig.