Ford 8N Lift Arms, Need Help... Still...

Well, I drained all of the Hydro Trans stuff out, and poured 4 gal of 80-90. It is just Harvest King stuff from Big R, nothing special, but it is thick!

I fired the tractor up, and it still does the same thing, but maybe not quite as bad.. If the arms are ALL THE WAY down, and the tractor is idling, with me sitting on the lift arms, someone can hit the lift lever and go all the way up with it.

The arms will shoot up about %20 of the way correctly, and then all of a sudden they just stop, and you can feel/hear a pulsing and the arms will continue to pulse slowly to the top, and I mean SLOW...

So? Should I go ahead and pull the pump then? I really didn't want to screw up the gasket and make a huge mess before trying it with the 80-90, so, I have tried it, and here I sit!

What do all ya'll think?

I would not get in a hurry about pulling the pump. Sounds more like a draft control problem to me. Hopefully some Ford guy will know.

Did you post this on the 9N 2N 8N site?
If so, they likely will tell you to remove the right side cover and look at what you see with oil movement.
If oil is dripping from above, your piston likely needs the ring upgrade kit.
This involves removing the top cover!!!
... and messing up your nice new paint.
There is tons of info over at that site, and many good fellows to help out.
That's my suggestion anyway.
Nboard

Well, after looking in my manual, it said to pull both the side covers and snoop around in there to see what it is doing... There is oil dripping down from somewhere, not sure where!!

If that is the case, then I guess I will probably just start pulling it apart... Paint can be repainted I suppose...

Thanks, Bryce

More info here.
Here

I would guess a bad seal on the lift cylinder.(in the top cover)

I think that I am on the trail of a bad valve... I had an interesting idea, and that would be, that if the arms have trouble going up due to a piston related problem, such as rings, or just a lot of wear, then the arms would come down quickly, because they couldn't hold pressure.

Well, I fired it up, and let it take it's time to get the arms ALL the way up to the top, I am sure of it, couldn't pick them up anymore. Then I shut the machine off, and just sat there and watch to see what would happen. I instantly heard a weird bubble noise, I look in, and below the pto shaft, air is bubbling up through the oil? So I go around and stand on the lift arms. They start to go down, in surges, and for evey surge there is a LOUD bubble in the oil. It went down about 2 inches, and then stopped. From this point, 400lb's couldn't make them budge.

So, if I am correct, that should eliminate any possibility of a piston related failure, right??

If that is the case, then I figure that it must be a valve, or the pump just can't get enough oil, but then how is a person suppose to explain why it does go up very well at first, and then it all falls apart????

Getting close, I can taste it...


However it tastes like 80-90... EEEWWWWWWWWWW!!!

Could be not enough fluid, or a pump intake sucking air after a lifting somewhat. If it lifts a 3 point implement well, but not all the way, that might be it. A damaged cylinder is also possible. Jim

Go to the Ford 9N, 2N, 8N forum and call out JMOR... He's a nice guy and can help you understand this system PLUS give a good diagnostic approach to your issue... You will get other help but stand up and pay attention when Jessie post...

LOL on the EEEWWWW line.

I have been reading with interest because I had a similar problem. In the trans cases there is a small metal line that runs vertical and takes the oil under pressure from the pump on the bottom up to the piston threw the top cover if I remember correctly. On my tractor that steel line had ruptured causing the arms to be slow and very weak. It sounds very similar to what you have. The bubbling you are hearing is the fluid being pushed back out that line. You will have to remove the top cover to verify, Which it sounds like your going to have to do anyway. Just be sure to get the lift handle rods in the proper position when you go back together. It's been a while since I fixed mine so time may have stole some of my memories! I think I had to take the pump out also to drive the old tube out, maybe you'll get lucky and it will come out the top, If that does happen to be the problem.

how or why the air? I would cycle the arms fully a number of times to be sure the air is fully purged before pulling it apart. did it sit for some time with no oil in it?

like was said, don't be in a hurry to pull the pump, that is a bear to remove and reinstall and the little valve in the bottom is really fragile and easily broken, but sounds like a leak or piston prob.