Hi all, I have a leaking front servo valve on my 93LTD gearbox, are the seals easy to change myself or do jou need special tools. are they just o-rings? Does any one have instructions for how to do this.

Never done a servo valve on gbox but one would assume o ring of some description like a copper ring similar to engine oil ?

It's just a rubber O ring, you need to compress the piston, and release the circlip, pop the piston out, and change the O ring, just be careful when you put it back in, as long as u put it back the same way it came out it should be fine.

Gab

Hi there, bought the 3 o-rings will put them on tomorrow. Here’s what I plan to do

Cleaned the box
Remove circlip on front servo
To force out servo piston screw in front band adjuster (on other side of box in relation to front servo?)
Replace o rings (3) on servo
Install cover and circlip
Adjust front band to10lb slacken of 3 full turns, tighten locknut to 40lb
Check oil.

Gab1, do I need to force piston out with the adjuster screw or have you done it without touching the screw?

Thanks all

Job done, my torque wrench only goes down to 13nm (need 10nm)so still need to tighten bands properly, also replaced seal on inhibiter switch. Test drove it, it chanches properly and no leaks. You need to hold adjusting screw when tightening locknut, so think about which spanners you can use.

If you took pics you should make a tech doco!! Can never have to many tech docos lol good work!