8N hydralic System

Have a 1948 8N that the hydraulic system has not been touched since new to the best of my knowledge. It is getting a little tired. It leaks down pretty fast when the motor is shut down, only reacts in part of the quadrant, and moves different amounts for the same lever displacement. I would like to go through the entire system and get it back as close as I can to its original state. Does anyone know where I might find a tutorial, or specific posts that would guide me through the process ? I have the repair manual, operators manual, and the ITT manual. This will probably be a winter project. Thank you in advance for any help or suggestions. You folks are great !

You should rebuild the lift cylinder and drop the pump for a good cleaning. Before you start, it would be a wise move to get a jig from Zane Sherman (http://www.bramblett.com/zane/ ) to adjust the internal linkage. And, make a couple of ?guide studs? by cutting the heads off of two 7/16-14 x 3 5/8? bolts. Also, if your lift cylinder rebuild kit has the leather washer, get CNH part number 87051231 which is the neoprene washer for the lift piston instead of the leather one.

The lift cover weighs nearly 100 lbs with the upper lift arms attached, & is very hard to maneuver. An engine hoist is an excellent idea. Remove the seat and spring, disconnect the upper lift arms at the knuckles. Remove the 14 bolts that hold the cover to the housing. (note that there are three different lengths) DO NOT remove the four nuts under the seat! Remove the right side inspection cover so you can remove the control rod tip from the pump intake valve. Lift the back of the cover straight up and slide a piece of wood under the cover to keep the tip of the control rod out of the rocker shaft. Once you are sure the control rod is out of the rocker shaft, you can then remove the cover. Turn the cover upside down, remove the four bolts that hold the cylinder to the cover, & use a little compressed air on the cylinder to remove the piston. Check the cylinder for excessive scratches, hone if necessary. ( Or just replace the cylinder & don?t worry about honeing it out too much. ) Install a new piston with "0" ring and backing washer in the cylinder. Install the CNH neoprene washer w/ the concave side toward the ?O? ring. At this point, check the cam follower pin & the control rod. If the cam follower pin is worn replace it. Then, if you have a jig, adjust the linkage to specs. The ?shade tree? adjustment was to bend the control arm to compensate for normal wear in the linkage, springs & cam follower pin. If the control rod is bent, remove it & straighten it. (very carefully; they break easily!) Replace the gaskets under the cylinder and bolt it back on the cover. Put the gasket on the tractor (no sealer) and put the guide studs in place. Unless you do this every day or have eyeballs in your finger tips, get some help to guide the tip of the control arm back into the rocker shaft. (this is the point you will wish you had a engine hoist to hold the top cover while the control rod dances around the intake valve arm on the pump!) Align the cover holes up with the housing holes. Remove the guide studs. Tighten cover bolts, connect lift arms install the seat. Re-install the inspection covers with new gaskets.

Now for the pump......

For info on the hydraulic fluid, check out tips 3 & 4 at the link below.

With all of the fluid drained out, block the front wheels & get the rear wheels up at least a foot. (you'll see why soon enough) Remove the 4 bolts holding the PTO shaft in & pull it to the rear & out of the tractor. Loosen all of the bolts. Remove all but 2 corner bolts. Then, carefully remove them. If you are lucky, the pump will drop free (and dump a pint or so of hydraulic fluid down your sleeves). If not, wrestle it free. The pump has 'ears' that fit into the housing; wiggle it a bit & it will drop free. If you have the rear tires a foot or more off of the ground, you will have enough arm room to hold the pump & lower it at the same time. Put it on your work bench & remove the safety valve (p/n 638) and the control arm lever (p/n 643) which will allow you to remove the intake & exhaust valves (p/n?s 640 & 698) Drop all of it in a bucket of diesel (or mineral spirits) or your parts washer & let it soak overnight. Once it has a good soaking, get it on the bench & start blowing it out w/ compressed air. Run cleaning fluid into the hydraulic discharge near the test port & make sure you get a good flow out the small hole in the side of the pump were the control valve fits. I don't see much need to pull it down any further just to clean it. But, I always replace the safety valve (p/n 638, about $25) Reinstalling the pump is harder than pulling it out because you have a gasket to worry about. (no sealer on the gasket) And, you will probably need a helper to guide the control rod into the pump rocker shaft unless you?ve done this 6 or 7 times before!

While you have the PTO shaft out, it would be a good time to replace the seal on it. It's got two spring clamps around it. Take your needle nose pliers & remove the one in the front. Then, hang the shaft & bearing housing in your vice & tap the butt end of the shaft; the bearing cap will come off (and the shaft will land on your foot). Then, remove the other spring clip from the other side of the bearing. At this point, remember that you never bought a seal driver & go get a BF socket & drive the seal out. If you have the new style seal, the white side goes out. (open side to the oil) Put some grease on it.

Contrary to conventional wisdom, not a lot of water gets in the oil from the shifter boot. Of course, if it's bad, replace it, but you get water from the draft control spring & the dipstick. But, most water is just a byproduct of the heating/cooling cycle of the oil.

You?ll need a pump gasket, safety valve, inspection plate gasket(s), PTO seal, PTO gasket, gasket sealer & 5 gallons of fluid to do all of the above.
75 Tips

I wrote a DIY article on easy 8N hydraulic repair when on a budget...my email is open so I can tell you what site Ford N-Series Tractor Club to go to and get a FREE download of it...

[i:654c4848f0][b:654c4848f0]<font size="4">Tim *PloughNman* Daley(MI)</font>[/b:654c4848f0][/i:654c4848f0]<table width="100" border="1" cellpadding="0" cellspacing="0" bordercolor="#000000"><tr><td height="25" colspan="2" bgcolor="#CC0000"></td></tr><tr><td> </td><td></td></tr></table>

(quoted from post at 06:15:55 08/11/17) I wrote a DIY article on easy 8N hydraulic repair when on a budget...my email is open so I can tell you what site Ford N-Series Tractor Club to go to and get a FREE download of it...

[i:9085e640c4][b:9085e640c4]&lt;font size="4"&gt;Tim *PloughNman* Daley(MI)&lt;/font&gt;[/b:9085e640c4][/i:9085e640c4]&lt;table width="100" border="1" cellpadding="0" cellspacing="0" bordercolor="#000000"&gt;&lt;tr&gt;&lt;td height="25" colspan="2" bgcolor="#CC0000"&gt;&lt;center&gt;&lt;font color="#FFFFFF" size="3"&gt;*9N653I* &amp; *8NI55I3*&lt;/font&gt;&lt;/center&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td&gt;&lt;img src=http://i.imgur.com/4lBA6Yh.jpg&gt;&lt;/td&gt;&lt;td&gt;&lt;img src= http://i.imgur.com/zzYVuC4.jpg &gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

Click to expand...

Hey Tim I would like to get the address of the forbidden site too,
my E-mail is beacon316atmsn.com Thanks ...Cliff

Here is a video available on Amazon for hydraulic repair on the 9N, 2N and 8N.

https://www.amazon.com/Hydraulic-Re...draulic+repair+for+ford+and+ferguson+tractors

Folks,
Many thanks for the many helpful suggestions. I sincerely appreciate your efforts.
Many Thanks

Hi Tim,
I do not how to get to your email. Could you possibly send the address where I can look your fine article up ?
Many Thanks
PS where are you in Michigan ? We are near Flint

look in the lower right corner of tim's post. u should see a "send email" link.