Hydraulic hose nut torque

[PointyHairedBoss]

I removed some cylinders from my B21 backhoe for bushing / pin service. When I put the hoses back on, do I torque them by feel or is a specific torque required? I looked in the service manual but I didn't see anything. If a specific torque is required, how do you do it since you can't use a socket?

 

[leonz]

Good morning,

You finish tightening the hose swivel by feel not torque.

You can break the swivel fitting on the hose very easily.

If it is a JIC 37 degree male female fitting set you should

be able to thread it on by hand quickly if the fitting and

threads are clean until resistance is felt and then tighten them

with a wrench and carefully watch the clearances of the swivel

and base fittling- the swivel will break before the base is damaged.


Do not use pipe dope as the JIC fittings will not tolerate the

pipe dope and they will break.


Why they have avoided using the horseshoe clamp fittings and o rings
is something I will never for the life of me understand as they are the simplest to own and maintain as they are fool proof and much easier to work with.

 

[PointyHairedBoss]

I just found this in the B21 shop manual showing tightening torques for hydraulic hose fittings.
What tool would you use on the nut? A regular socket won't work because the hose is in the way.

 

[oldnslo]

I just found this in the B21 shop manual showing tightening torques for hydraulic hose fittings.
What tool would you use on the nut? A regular socket won't work because the hose is in the way.

Crows foot. When using these you have to either keep the craws foot at 90 degrees to the torque wrench or calculate the added length of the craws foot and reduce the torque setting accordingly.

Use a little common sense and tighten by feel will usually get you by. Do NOT try and tighten a fitting while it is under pressure. They are already stressed and and pulling on the wrench may make them fail.

Roy