Calling on the rebuild experts !! Bearing clearance

Legion

Registered User
Got a question. What's the specs for bearing clearances.and what's the deal with plastigauge and these engines? Used it before but some say the last bearing rear main..is .10 thousands smaller ? Anybody have specs and any advice on plastcgaugeing the bearing to crankshaft clearances. ?
 
Rear main's on S/C are .010" undersize

I was told this ensured that they did not try to drop in the cast crank for the N/A engines
rather then the forged one for the S/C"s at Essex plant. Not sure if that's true or not ?
 
Yeah that's why I'm wondering? I also figured out that the 96+ blocks from N/A 3.8s aren't the same as SC blocks. They use smaller main caps and 3/8th bolts rather than 7/16 main bolts I believe.the main bolts and caps for the 96+ are pretty small
 
Cool article !

So, I was right about the reason they used a .010" undersize main on the rear of the S/C engines.
My uncle worked in final balancing at Essex plant & told me this fact when I bought my first T-bird with
the S/C 3.8. (already had some Turbo Coupes prior to that)
 
Last edited:
Not to jack up the thread, but...

"Camshaft:

There were two different types of camshafts designed. Automatic and manual transmission cars each had their own unique camshafts. They were color coded yellow for the ATX version and pink for the MTX version. The paint was applied to the rear end of the camshaft."

What affect would the ATX camshaft mounted to a manual transmission have? I never really paid close attention when I had a Ford dealership replace my original engine with a fresh-order reman directly from Ford a few years ago. Interesting if anyone knows what the difference is, and what it does. I'm not looking to tear my engine down just to find out though, fyi. :rolleyes:
 
Well this got all ~~~~ity ....1/2/3 mains all gave me a little over the 15 thousands of an inch on the plastigauge strip. Then the last one 4 gave me a little over 2 thousands of an inch on the strip....all torqued to 80lbs. How far out of spec is number 4 main? I keep getting all kinds of clearance numbers from different members and Google searches..lol...kinda frustrating. The last bearing seems to be a little small. Also will the main caps on a 3.8 n/a be fine to run on if I decide to build an n/a block to SC conversion? I have a second SC crank. there isn't much info on rebuilding or building this block other than here. And the numbers I keep getting are not consistent lol...
 
Last edited:
there isn't much info on rebuilding or building this block other than here.


Much of the info here is pulled directly from the Ford Thunderbird/Cougar Shop Manual. Those are still available via manual suppliers, eBay and private sales. Section 21-01-15; Journal, Refinishing & Fitting Main or Connecting Rod Bearings with Plastigage - total 14 paragraphs.
 
Back
Top