PA-28R-180 brake caliper bolt torque

iamtheari

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I have the great fortune of needing to put in a new main landing gear tire tube to replace a brand new one, which was leaking after 2 perfectly good landings and which was installed at nighttime rates thanks to not leaving my name and number at the FBO during the day. And I get to order it overnight delivery so I can put it in before I head to Oshkosh, of course. That's not a big deal and it should all be pretty clean since it was just done.

But I don't know the torque spec for the brake caliper bolts. Does anyone happen to have that information or a service manual with that information handy? Thanks in advance.
 
What size bolt. Should be able to look up torque values if you know bolt type. 1/4-28 torque is 50 to 70 in-lbs
 
I have the great fortune of needing to put in a new main landing gear tire tube to replace a brand new one, which was leaking after 2 perfectly good landings and which was installed at nighttime rates thanks to not leaving my name and number at the FBO during the day. And I get to order it overnight delivery so I can put it in before I head to Oshkosh, of course. That's not a big deal and it should all be pretty clean since it was just done.

But I don't know the torque spec for the brake caliper bolts. Does anyone happen to have that information or a service manual with that information handy? Thanks in advance.

If its a Cleveland (now owned by Parker) brake, they have a pretty nice vender component maintenance manual.
 
I found the Cleveland component maintenance manual online so I just need to find the part numbers of my wheel and brake assemblies and I'll have it made in the shade. Failing that, and probably as a backup to that information, I will also be able to find a standard torque value for the bolt size and grade. Things that seem obvious but which I needed your help to see. Thanks!
 
Aren't these bolts threading into a (edit) steel backing plate?
Thinking the torque will likely be different than that in the AC43.13 shear/tension charts, which I believe are for nuts. The aircraft service manual might be the best place, unless this is a modification.
 
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Aren't these bolts threading into an aluminum housing?
Thinking the torque will likely be different than that in the AC43.13 shear/tension charts, which I believe are for nuts. The aircraft service manual might be the best place, unless this is a modification.
I don't have the aircraft service manual.
 
Per the thread title, this is a PA-28R-180 which is the original late 1960's Piper Arrow with the Hershey bar wing.
 
Per the thread title, this is a PA-28R-180 which is the original late 1960's Piper Arrow with the Hershey bar wing.
PM me, and I'll email you the PDF version of the service manual. Parts, too, if you want.
 
I believe all the info you need is in the Cleveland (parker) wheel and brake manual and product catalog. Calipers are usualling 50-70 inlbs and wheel half assembly are 90 inlbs.
 
Caliper bolt torques aren't in the aircraft service manual. You won't find engine bolt torques there, either. The OEM manuals will tell you to refer to the component manufacturer's manuals for such information.

The Cleveland calipers, if the bolts are AN4's, will be around 70 or 75 inch-pounds. I often found them torqued way beyond that, and have seen a failed caliper when the bolts broke. I have found bolts stretched in the threads from overtorquing. Look closely at those bolts for any stretch in the threads immediately under the unthreaded shank. Don't use them if they're not good.

Wheel bolts will be around 90 in-lb if they're AN4s. Cleveland also used a lot of AN5 bolts, and the torque is 150 in-lb. Wheel bolts are often ovetorqued as well, and they need similar inspecting. I don't need to tell you what failed wheel or caliper bolts can result in, do I?
 
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