Correct rod bolt torque? 6pt vs. 12pt? And unrelated TM error.

[M37M35]

I'm FINALLY getting around to putting my deuce engine back together after finding a crack in the block behind the #6 liner.
https://www.steelsoldiers.com/showt...nkcase-vent-Small-amount-of-antifreeze-in-oil
https://www.steelsoldiers.com/showt...n-appears-slightly-melted-What-to-do-about-it

What is the proper torque for the connecting rod bolts? I have the 12 point bolts.
TM 9-2815-210-34-2-2 says it covers the LDT engine, and page 671 says 95-100 FT-LB. The drawing shows 6 point bolts. (If that means anything)

But this thread says 85 FT-LB for the LDT engine. It doesn't say which TM.
https://www.steelsoldiers.com/showthread.php?152518-Rod-bolt-torque&highlight=rod+bolt+torque

I haven't seen any mention of 6 point versus 12 point rod bolts in the TM. Is there a different torque spec for the 12 point bolts?


Also...
The error I found is in the same TM, page 817. It says torque the injector hold-down clamp bolts to 150-175 FT-LB. I'm pretty sure that should be IN-LB... That makes a lot more sense for a 5/16" grade 5 bolt.

 

[M37M35]

Anyone have any thoughts on this??

 

[cattlerepairman]

1) use the torque that you already mentioned: https://www.steelsoldiers.com/showthread.php?152518-Rod-bolt-torque

That is the torque I used when I put the upgraded bolts in and they are still in there!

2) the torque for the injector hold-downs is indeed wrong in the TM. Known error.

 

[M37M35]

Thanks for the info! And glad your rod bolts are staying put!

Since TM 9-2815-210-34-2-2 says 95-100 FT-LB for both LDT and LDS engines and was printed in 1981, I thought that might be the new specification for the upgraded 12 point bolts.

Several generic bolt torque charts I found said that size and grade bolt should be torqued to 90 FT-LB. So I split the difference between the 85 and 95 spec, and torqued them to 90 FT-LB.



The torque charts I found say a 5/16" grade 5 bolt should be torqued to 13 FT-LB, which would make the TM correct if it specified IN-LB instead of FT-LB for those bolts.
I didn't know it was a known error, but now I know that it's known.

 

[rustystud]

I'm FINALLY getting around to putting my deuce engine back together after finding a crack in the block behind the #6 liner.
https://www.steelsoldiers.com/showt...nkcase-vent-Small-amount-of-antifreeze-in-oil
https://www.steelsoldiers.com/showt...n-appears-slightly-melted-What-to-do-about-it

What is the proper torque for the connecting rod bolts? I have the 12 point bolts.
TM 9-2815-210-34-2-2 says it covers the LDT engine, and page 671 says 95-100 FT-LB. The drawing shows 6 point bolts. (If that means anything)

But this thread says 85 FT-LB for the LDT engine. It doesn't say which TM.
https://www.steelsoldiers.com/showthread.php?152518-Rod-bolt-torque&highlight=rod+bolt+torque

I haven't seen any mention of 6 point versus 12 point rod bolts in the TM. Is there a different torque spec for the 12 point bolts?


Also...
The error I found is in the same TM, page 817. It says torque the injector hold-down clamp bolts to 150-175 FT-LB. I'm pretty sure that should be IN-LB... That makes a lot more sense for a 5/16" grade 5 bolt.

Sorry I didn't see this earlier. I was off line for a few days. The 12 point bolts are a stronger replacement for the older 6 point bolts. The torque should still be the same though.