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Lift cyl clearance? 9n upgrade to O-ring...

3022 Views 4 Replies 3 Participants Last post by  soundguy
Anyone out there know what acceptable clearance (piston to bore) I'm looking at for the lift cyl on my 9N? I've got 2 cyls (one's out & the other is in operation).

I was hoping to get the spare ready to go for the rebuild - make it a simple swap instead of pull it and fix stuff and then put back together.

I haven't priced a replacement - I'm told I could have it electroplated and re-honed (buddy's got a machine shop) for under $40....

What's acceptable clearance with the O-ring NAA setup?

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clearance? -0- interference fit.. that's why it's a oring.. if there was clearance.. your lift wouldn't work :)

now.. that said. if you look at the max cyl tolerance for using the steel rings.. you can actually hone slightly oversized and still get away with a genuine fat CNH lift piston oring and have good contact ( takes lube and a couple spoons to get the piston into the bore with oring even after honing out of spec )... smaller tisco orings.. you want to stay inside spec.
CNH case new holland.

the bore spec is in the fo-4 service manual.

i wouldn't worry mouch about the piston to cyl clearance itself.. just overall bore spec with reguard to the oring once compressed into that piston ring land with the appropriate backup washer in the correct location.
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