C160 auto Hydraulic valve leaking

[CNC 19]

I have a C160 automatic the hydraulic valve is leaking fluid. I have replaced all the hoses, had the cylinder and value rebulit . it still leaks at the valve assy. I am at my wits end! Has anyone had this problem  or any suggestion?

Thanks 

[peter lena 9,924]

@CNC  only thing  I can think of  is o ring  seal , rolling  due to  dry  installation   ?  as tightened , if not properly  lubed , the rings , grab and bind , twisting  smaller  tighter ,  making a leak area , regularly used SUPER LUBE ,  hydraulic  lubricant ,  my suggestion , pete

[ebinmaine 79,392]

1 hour ago, CNC said:

rebulit

 

Can you see exactly what seam or joint is leaking? 

[CNC 19]

46 minutes ago, ebinmaine said:

 

Can you see exactly what seam or joint is leaking? 

It looks to me like it leaks from the hose that is 11 in. long that goes from front of valve assembly  to back hole in the cylinder 

I have a friend that is coming over after the 4th who knows more about hydraulics to check it out and see where he thinks it is leaking.

[pfrederi 20,799]

23 minutes ago, CNC said:

It looks to me like it leaks from the hose that is 11 in. long that goes from front of valve assembly  to back hole in the cylinder 

I have a friend that is coming over after the 4th who knows more about hydraulics to check it out and see where he thinks it is leaking.

 

Possible the O ring was damaged during installation....

The hose end could be an SAE #6 ORB (O Ring Boss)  or SAE#5 ORB  #6 threads are 9/16NF   #5 are 1/2" NF

 

The orings are Dash #906  or Dash # 905

[Handy Don 16,843]

ORB fittings depend on smooth, continuous, debris-free seating of the O-ring between the body of the fitting and, in this case, the cylinder body.

To be ready when your friend comes, have the IPL handy when s/he comes. 

[953 nut 67,073]

Torque settings for ORB fittings should be made in accordance with this chart. Too tight will kill the "O" Rings.  You will need to use a crows foot placed to the side of the torque wrench to get a correct reading.

            JIC                                                             ORB

 

Size          SAE Thread            Torque                Size          SAE Thread            Torque         

 

4                7/16-20                 140 In/Lb              4           7/16-20                     220 In/Lb

5                 ½-20                   180 In/Lb               5             ½-20                        260 In/Lb           Dash# 905 O Ring

6                9/16-18                 250 In/Lb              6            9/16-18                    320 In/Lb           Dash# 906 O Ring

8                 ¾-16                     550 In/Lb             8             3/4 -16                     560 In/Lb

[pfrederi 20,799]

That is great info!!!!

 

I probably over tighten mine

[ebinmaine 79,392]

45 minutes ago, pfrederi said:

That is great info!!!!

 

I probably over tighten mine

 

I definitely do. 

Bear tight. 😬

[WHX?? 57,194]

3 hours ago, 953 nut said:

Too tight will kill the "O" Rings.

Absolutely true. They must be torqued to spec. 

[pfrederi 20,799]

Slightly off topic ...I know when you use a crowfoot on a torque wrench facing forward yo have to adjust the torque setting.  If you have it to the side as in the picture do yo have to make an adjustment??

[ebinmaine 79,392]

37 minutes ago, pfrederi said:

Slightly off topic ...I know when you use a crowfoot on a torque wrench facing forward yo have to adjust the torque setting.  If you have it to the side as in the picture do yo have to make an adjustment??

 

 

I was taught that a crowfoot ALWAYS uses different readings. Rotation position didn't matter. 

 

I use one so little that I have to look it up every time.  

[ebinmaine 79,392]

Here's a tech tip video showing the increasing lever effect.  

He shows that a 90⁰ offset does not increase the value. 

That's different from what I learned years ago.  

I see his logic but I was told to allow LESS difference. Not equal.  

 

 

 

 

 

 

 

 

[pfrederi 20,799]

Found this if you trust AI

 

 

[pfrederi 20,799]

and of course it is impossible to get a torque wrench on the center back hose on the control valve  so feels about right torque is the answer.