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Torque settings on LM340 manifold

A

aday_in_nh

Member
"Getting ready to reinstall ex

"Getting ready to reinstall exhaust manifolds on an LM340. Can anyone tell me what the torque settings should be on the mounting studs? Also, torque settings on the end caps and exhaust risers would be helpfull too. Thanks and Merry Christmas."
 
"Throw that torque wrench away

"Throw that torque wrench away! (It's the most destructive tool in a mechanic's toolbox.) Simply seat the bolts, then add a flat or two at a time 'til they are tight. And I'm assuming you used clean, new bolts in tapped-clean holes, with anti-seize on the threads?

Jeff"
 
"Yes, new bolts/studs, clean h

"Yes, new bolts/studs, clean holes, and anti-seize. Can you translate "a flat or two" for a novice? Thanks."
 
"Hard to translate--we're

"Hard to translate--we're talking 40 plus years experience here! Basically, you tighten the bolt until it's good and snug, starting from the center bolts and working your way outward in each direction. Then add a few flats (1/6 of a revoultion) at a time until it's a bit tighter. Use anti-sieze on the threads, and use NEW grade 8 (six marks on the head) bots. Do NOT use stainless bolts! Far too weak.

Jeff"
 
The service manual calls for 3

The service manual calls for 30 ft. lbs. of torque on those bolts. Remember to check them again after you have a few hours on them. I got about "one more flat" on several of mine after running about 10 hrs.

Ed
 
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