9N no hydraulic lift after replacing draft control plung

[MeAnthony]

Good evening, all

This seemed like a pretty straight forward process but I obviously buggered something. Hydraulics were fine before replacing the busted plunger. I ran it for probably at least a year with a pair of Vice Grips holding the old plunger stub out a ways just so the lift would work.
Thinking back over it now, there are a couple details that seem like they could have contributed to this issue:
1) the lift was lowered when I removed the top cover. When putting it back on, I know I flipped the lift shaft arms (#59 in diagram below) up to what would have been the raised position. Maybe the connecting rod (#47 in diagram below) came out of place?
2) at one point prior to reinstalling the control spring and yoke, I leaned on the draft plunger and it popped back in a few inches. Would this have dislodged something?

I think the worst part of this job was getting that darn T for the hydraulic exhaust valve back into the fork. Wow! It was a struggle to my arm in there!

 

[Tim PloughNman Daley RIP]

Are you sure you have a 9N pump and not an 8N? What is the plunger stub??? Do you mean the Selector Lever next to the RH seat? If so, you have DRAFT CONTROL and POSITION CONTROL, only on the 8N Pump. #47 is the ram for the piston in cylinder. Did you do a leak down test first? All that work pulling the Top Cover and you didn't replace the cylinder and piston, clean or replace the chambers, replace the safety relief valve? The 9N/2N Pump has a wishbone Connecting Bracket, the 8N has a Control Rod for Position Control/Draft Control selection. Contact me --- my email is open.


Tim Daley(MI)

 

[MeAnthony]

Good morning, Tim

I did respond via email but posting here also.

Yes it's a 9N pump.

The draft control plunger had broken in half. Since the hydraulics don't work at all without the draft control plunger being held out, I simply pulled the plunger (now a stub) outward and clamped a pair of Vice Grips on it in lieu of the control spring, see photo below.

I did thoroughly clean everything but did not replace any other parts because the hydraulics worked great. There were no lift or leakdown issues. The previous owner was a maintenance guy and I'm reasonably sure he's already been through it.

 

[Tim PloughNman Daley RIP]

OK, got it. I'll reply by email in a bit. Don't guess. Do the leak down test first. Attach a load like plow, mower, or back blade. Raise it all the up and leave it up then shut down engine. Note if the load drops in a few minutes, a few hours, or few days. A properly functioning system will keep a load raised full for months. If the first part of test fails, repeat load raising and remove side inspection covers on center housing. With a Mini-Mag look way up under the top cover to the cylinder and watch close for sings of hyd oil seepage. Yes? You have a worn cylinder and needs replacing. Get new, don't think you can just hone out -that won't do anything. Also get teh new style piston, p/n NAA-530-B with rubber O-Ring and leather wiper. The Manuals have the system directions on how to adjust linkages and lift control. Carpenter has some new parts including the ram arm and all rera lift parts but you might want to consider finding a used 9N Top Cover intact with the cylinder and linkages. Rebuilding is not a difficult job, just time consuming. There is a good video from J&D Productions on D-I-Y repairs. Search them or farmtactorrepairs.com


Tim Daley(MI)

 

[Hobo,NC]

Will 47 drop out on install I dunno other than it will on a Ford 3000.

Remove the inspection cover on the right side with a mirrow check it.


I leave the drain plug out so I can tell if the linkage is connected to the control valve. I have someone work the linkage while I am looking thru the drain plug hole : )





https://forums.yesterdaystractors.com/viewtopic.php?t=1499691&highlight=jim

 

[MeAnthony]

#47 in the parts diagram did not drop out. Both pivot pins in #53 Lift Control Lever Fork came out. I fished around inside with a magnet but only found one pin. I worked on it from the right side of the tractor and know for sure the right side pivot pin was in there throughout initial disassembly and reassembly. Honestly I didn't look at the left side and I didn't look at the locking cotter pin in the right side pin. The cotter pin must have already been gone and my wiggly-jiggly to get the hydraulic exhaust valve T back into the fork holes worked the pivot pin partially out? Then vibration from the cordless impact used while tightening down the top cover knocked it completely out? Best guess, anyway. It does work now that both pivot pins are replaced.

I did recently replace seals and gaskets on the rear axle. During this process I found the other mystery parts below in the bottom of the differential. Maybe that's the pivot pin from the left side of the fork? Depending on which way it flung when it came out, it could have bounced off the case side and gone through the casting hole at the top of the ring gear? Again, just my best guess.

 

[JMOR]

(quoted from post at 21:24:44 09/10/21) #47 in the parts diagram did not drop out. Both pivot pins in #53 Lift Control Lever Fork came out. I fished around inside with a magnet but only found one pin. I worked on it from the right side of the tractor and know for sure the right side pivot pin was in there throughout initial disassembly and reassembly. Honestly I didn't look at the left side and I didn't look at the locking cotter pin in the right side pin. The cotter pin must have already been gone and my wiggly-jiggly to get the hydraulic exhaust valve T back into the fork holes worked the pivot pin partially out? Then vibration from the cordless impact used while tightening down the top cover knocked it completely out? Best guess, anyway. It does work now that both pivot pins are replaced.

I did recently replace seals and gaskets on the rear axle. During this process I found the other mystery parts below in the bottom of the differential. Maybe that's the pivot pin from the left side of the fork? Depending on which way it flung when it came out, it could have bounced off the case side and gone through the casting hole at the top of the ring gear? Again, just my best guess.
<img src=https://www.yesterdaystractors.com/cvphotos/cvphoto100704.jpg>

all me 'doubting thomas'.

 

[MeAnthony]

Not sure what your point is, only guessing that you have a different explanation? Can you clarify please?

 

[JMOR]

(quoted from post at 07:40:27 09/11/21)
Not sure what your point is, only guessing that you have a different explanation? Can you clarify please?

o, just thinking of the odds of that control fork pin getting thru the casting hole near top of ring gear. What would that number be?