engine rebuild and torque question

romgolferman

Founding Member
Mar 24, 2001
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St. Louis
Ok i torqued the main caps to 20ft lbs then 90 degrees. crank spins fine. then i put on the rod caps and torqued them to the same 20ft lbs then 90 degrees. the crank wont turn. plugs are out so no compression. when i torque the rod caps to just 20ft lbs everything turns fine. when i go the extra 90 degrees the book says to the crank wont spin.
 
My 02 GT shop manual says the main caps should be tightened to 30 ft-lbs and then an additional 85-95-degrees. What reference are you using that says 20 ft-lbs + 90-degrees?

For the rod bolts it says 18 ft-lbs (stg 1), then 30 ft-lbs (stg 2) followed by 90-degrees.

You should install one piston/rod assembly at a time and check for rotational issues.

It sounds like you've clearly got one or more rod bearings that have insufficient oil clearance. I'd beg, borrow or steal a bore gauge and micrometer to measure the crank journal and bearing bore diameters to determine your oil clearance.

BTW, the rod bolts should be replaced. They are torque-to-yield and stretch and permanently deform on that 90-degree tightening. If you re-use them, you'll weaken them and risk a bolt failure down the road. Every time a TTY bolt is stretched it should be replaced.
 
haynes manual says 18 to 25ft lbs then 85 to 95 degrees. at 25ft lbs the crank spins fine but that extra 90 degrees make the crank feel really tight and real hard to spin. i didnt change the bolts but i guess now i will. i didnt know you werent suppose to reuse them. i am about to throw this motor in the river.
 
haynes manual says 18 to 25ft lbs then 85 to 95 degrees. at 25ft lbs the crank spins fine but that extra 90 degrees make the crank feel really tight and real hard to spin. i didnt change the bolts but i guess now i will. i didnt know you werent suppose to reuse them. i am about to throw this motor in the river.

Like we said... try doing each rod cap individually to see which one(s) are binding up the works.