thermostat housing torque spec discrepancy

[TheOldMan]

SO, in the service manual, about page 165 or so, reading the spec for tightening on a LH2 motor....it says to tighten
the thermostat housing bolts to 20 N.m or 15 ft lbs. In the specs in the front of this section it says to tighten them 10N.m or 89 in lbs.
Which one to use?

The section is titled ENGINE COOLING

Dennis

 

[Gord]

Hi Dennis,
Common sense imho says 89 in-lbs is low. That's 7.5 ft-lbs by my quick math. With a decent torque wrench I'd have no problem to snug them down to 10 ft-lbs. 6mm fasteners I do believe so they should easily handle the 15 ft-lbs if you care to go a bit tighter.

 

[TheOldMan]

I had an idea that 15 ft lbs was going to be okay, just that the block is aluminum and me as Magilla Gorilla
tend to over tighten. Yeah I have many torque wrenches and will use one.

 

[mickeytee]

Snug plus 3 minutes or 10 degrees works for me.

 

[TheOldMan]

Thank you, I will try this method and see if I don't break anything off.

 

[TheOldMan]

Well, I torqued the three bolts down to 15 N.m ( 11 ft lbs )( half way between the written documentation torq specs) and seems to do the job. Thanks for all your help.