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318 crankshaft assembly 101

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Brock69

Member
I am in the process of replacing a cracked block and installing new Bearings and Piston rings.

I first checked to confirmed that the crankshaft was compatiable with the replacement block and it was. ( block casting #'s are the same)

Installed new Main bearings and then installed the crankshaft into the block and torque to 85ft/lbs

The crank does not turn at all and I want to confirm that it should turn freely.

The new bearings are standard and appeared to match the old bearings.

Even if the crank had previously been machined standard bearings should not prevent the Crank from turning ???? The pistons rings are .020 and the block was bored to .020

Any thoughts are appreciated.
 
not sure how much ur already invested for but i bought a long block for replacement from rapidomarine.com and it worked really well for the rebuild. Just replace my 318 this season
 
Yes, it should turn.....but it should take some effort.

Did you go with rope or neoprene rear seal? Rope often makes for a very tight seal and takes some time to wear in.

If you've already installed rods and pistons, check the torque on the rods and be sure pistons are facing the right direction.

And to answer your question about the crank having been turned....if it had been, it should actually be easier to turn with the stock-spec bearings. Having said that, it's worth double-checking/confirming that you do, in fact, have stock-spec bearings......because if they were sized for a turned crank, and the crank was stock, they'd be too tight.
 
As I understand it, you have ONLY the crank in the block and it won't turn. If so, that is no good at all! It should spin freely, and even with the rear main seal in place. I suspect you have oversize bearings in there by accident. (They make 0.010 to 0.030 oversize bearings).

Try this: Buy some Plastigage and check the clearance (if any). You should have been doing this all along, by the way. It's Russian Roulette to trust that clearances are "okay".

Jeff
 
Thankyou for your replies.

The reason that I ordered STD bearings was based on the part numbers from the old bearings.The letters STD was found on all the bearings.

Maybe someone can recognize the manufacture for these part numbers .

Bearings 1-2-4 2131 RAAU STD NL

Bearing # 3 FM 2132 RAAL STD CO

End Bearing 2143 RAAU STD RZ

I tried to ID these numbers and was not successful. Federal Mogul told me that these were not their numbers. I have my doubts about the person I was talking to.
 
Silly question but did you use assembly lube on your bearings and oil on your rings? Jeff is rite about plastigauge, I've never built an engine without it. Did you try to turn the crank before installing the rods?
 
Since the crank won't turn I'm sure you don't have any piston/rod assemblies installed.
Are the main caps for "that" block?
Are the caps on the proper journals and correct orientation?
Did the bearing shells fit in the caps and block completely?
Did you polish and mic the crank to verify diameters for standard size bearings?
Plastigage and assembly lube are a must.

Interchange chart link ..........
http://www.king-bearings.com/cat/html/interch.htm
 
Dave69

I did not keep the Main Bearing Caps that came with the replacement block

I am being told that the Caps from the cracked block will not fit the replacement block.

A vey expensive rookie mistake

Thanks
 
Aaauughh! No wonder that sucker wouldn't turn!

Jeff

PS: My cousin George did that while building his first 327 Chevy. It ran, but not for long.
 
Dave - it might be a rookie mistake but at least you were on-the-ball enough to catch it when you did. Better than finding out the way Jeff's cousin did.
 
If you can't retrieve the original caps you still might be able to align bore the block with the caps you have. Check with your local automotive machinist.


Align boring machine ..... An align boring machine for boring bearing housings of an automotive engine block wherein a boring bar is rotably suspended by and rotably driven between two columns positioned upon machine ways, and the engine block is mounted for aligned movement along said ways.


I would not try to re-use the main bearings you have installed already.


Check that crank, make sure you didn't hurt it (flat spots, scuffing, etc.)
 
Have to disagree here: Time to toss out that block and go with another. By the time you pay for align boring the block and a set of new bearings (plus possibly turning the crank down), your $$ would be better spent on a new long block.

Jeff
 
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