Another 8n 3 point lift question

[jcgbranson]

For some reason the touch control lever for the 3 point on my 8n is stuck in the full down position. Can't raise it for anything. Also, I tried to move the position control/draft control lever and it is stuck as well (position control). I have used the 3 point arms regularly and can't imagine why any valves would be froze up but who knows. I am imagining some linkage binding up but really have no idea. I haven't removed the inspection plate yet and wanted to check here to see if anyone had any ideas for me. Hydraulic fluid is good and pump runs fine.

 

[jcgbranson]

C'mon Soundguy...don't let me down here. From what I understand, you are the local expert on all things Ford.....

 

[Soundguy]

I don't know about that.. however the ford 3pt lift mechanism is just a rube goldberg system if levers and springs mostly..

first what i would do is spray the draft lever down where it enters the cover with a penetrant oil. next i'd back the tension nut off the 3pt control and try to leverage the handle and friction plate back a bt using 2 screwdrivers.. then spray in some penetrant oil. hose it down.

next pull the inspection cover and stick yer hand and that can of penetrant up in there and hose down the underside of the top cover.. paying attention to try to get it on the backside of where those 2 controls enter.

let it set a few hours.

not take a small hammer like a tack hammer and just tap onthe housing near the openings.. then tap onthe levers themselves in the directions they move.

if you are lucky.. they will free up.

if they remain 100% solid. you will be pulling the top cover.. which in and of itself is not a big deal.. just a gasket or 2 and some heavy lifting after you get the 3pt knuckles apart.

post back

 

[jcgbranson]

I pulled the tension nut, spring and plate off the control arm. Also match marked and pulled quadrant cover off. Lubed and tapped on the draft lever....got it to where it will move maybe half inch or so but it definitely hits something solid "in there". Control arm is still stuck way tight. Looking at the manual I was wondering if the exhaust port valve is stuck tight (since the control arm is in full down position). Was gonna gently tap on exhaust or intake valve (whichever is stuck out) but the draft lever moving just a lil bit troubles me. Could the draft lever be an issue with the ram cylinder? Or maybe just some linkage binding up? Seems odd to me that BOTH the control arm and draft lever issues happened at the same time.

 

[Soundguy]

all linkage at this point.

thru the inspec port.. you should be able to move the valve ( and control rod full inand out of the pump.. the rod should be quite spring loaded... at this point.. I'm guessing you will be pulling the top cover..

 

[jcgbranson]

Pulled the inspection port. Unlike a lot of horror stories, oil was beautiful with very little sludge in sumps. Control arm "wants" to move at bottom near valves but is bound up toward the top along with draft control lever. Will be pulling top cover this weekend. Anybody have ANY idea of what I should be looking for as far as broken/damaged/bent linkage or possibly a stuck top cylinder?

 

[Soundguy]

will have NOTHING to do with a stuck top cyl!!!

you could WELD the piston into the cyl bore and still move the 3pt control full stroke.. and all it would do is make the pump go into relief!!!

heck to make sure the pump valve is not bound up.. you can move the lower portion of the arm in it's lil rocker in and out, and that will make the 3pt go up and down if pto is running.. reguardless of what the 3pt control is doing.. IE.. as long as you manually move the rocker.. etc.


pulling the top cover is straighforward.

leave th 4 centr bolts.. they hold the cyl to the cover.

get all the top cover gaskets.

pull knuckle and 3rd point linkage.. get her off and flipped over on a bench.

sometimes the top cover dsticks because some moron glued it on with gasket sealer ( use NO gasket sealer on any of the hyd component paper gaskets... )

to pop the cover off if a moron glued it on.. use a bottle jack and piece of 2x4 and wedge it under a lift arm upper ear and pump the jack up so the cover is supporting tractor weight a bit.. then thumb the union of the cover to sump with a deadblow hammer. dont be near a tire.. etc.

if nada.. let it set.. let gravity do your work.. it will pop off.


DO get ALL the perimeter bots out FIRST!

 

[Soundguy]

ps.. have a servie manual handy so you can adjust the lift mechanism...

 

[jcgbranson]

Thanks for all of your help soundguy. Pulled the top cover over the weekend. Really not a bad job at all. My problem was quite simple actually. No broken, bent or worn parts at all. As I'm sure you know, the main shaft/bolt from the control arm extends into the case and has a couple of "cam" pieces (I guess you could call them) that slide on the shaft. One of those pieces was stuck tight to the shaft and the draft control spring and square shaped rocker were stuck tight. Pulled all the linkage apart and thoroughly cleaned and lubed and reassembled.

 

[Soundguy]

cool deal.