floor jack headache

[lestat]

Anybody here knows their way around a floor jack? About 2 weeks ago I found it on the floor leaking and thought it needs seals replaced. Because of lost oil, I had a hard time pushing the lift up but once I did it stayed up no problem. Now I'm pretty sure I just stored it sitting vertically against the wall with the universal joint/valve open and that's why it was leaking, so it might not be anything wrong with it after all, just an oil top up.

Anyway, before I thought about that I did proceed to take the back piston spring out, pushed the piston in a few times and now I can't seem to pull the piston out no matter what I do. I turns around quite easily if I use a pair of pliers though.

I can't take off the square drive piece either, I tried with a 26mm wrench and it almost broke my back. Next thing is to use a cheater bar but I'll have to go buy a cheap wrench for that and cut it's ring head off.

Anybody knows the inner workings of that jack, why would the piston get stuck like that?

Many thanks

 

[Hiball]

Umm... It could be hard to pull account its trying to **** oil. There's a Reason it has that big spring on it. If you cant figure a way to pull the piston out, You will have to remove the piston assembly (unscrew it from the unit) Then it should retract with ease. You cant pull that piston completely out because it has a shoulder on it, It has to come out the other way.

Steven

 

[lestat]

Thanks Steven, I'll keep working that piston assembly. It will come off eventually.

 

[lestat]

update: I managed to unscrew the piston assembly. It looks like it had some locking compound on the threads. Anyway it's all making sense now. Last week I had it over at a hydraulic shop down the road to have it serviced and they said they couldn't get the screw off but they wouldn't want to force it either. I said ok, I'll come and pick it up. However, it appears they did have a good go at the piston assembly and their wrench must have slipped off the nut a few times, causing the hole at the top to taper slightly inwards at the top. That's why I couldn't get the piston out, it couldn't get through. A bit of grinding with a dremel fixed it right back.

Now, I'm having a really hard time bleeding the thing. Followed these instructions here:

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
1. Place Jack on flat, level and solid surface.
2. Turn the Breathing Screw (14A) fully counterclockwise. (See Figure 1, below)
3. Turn the Handle (20) to a position where the Discharge Valve is closed enough for the Saddle (41) to rise when you pump with no pressure on the Saddle, but open enough so that the Saddle does not rise when you pump with one hand while applying pressure to the Saddle with your other hand. (If the Saddle is up, turn the Handle slowly counterclockwise until the Saddle begins to go down slowly. If the Saddle is down, while pumping quickly, turn the Handle slowly clockwise until the Saddle begins to rise.)
4. While holding down the Saddle with one hand, rapidly pump the Handle with the other hand, so that air comes out from between the Breathing Screw and the Oil Plug (13A). Continue pumping until air stops coming out and you see oil appearing between the Breathing Screw and the Oil Plug.
5. Tighten the Breathing Screw by turning it clockwise as far as it will go.
Then turn it 360° counterclockwise.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


I've done it before when there was some air in the system and it worked perfectly: 6.5 strokes to the top. Now I can't get it to work right. I bleed the air out until i see oil, tighten the screw only to get anywhere between 10-20 strokes. After a few trials I top up some more oil and start again with no success.

Is there another technique I could try?

Thanks again

 

[Hiball]

Rule #1 Make sure there is plenty of oil in the resevoir. Turn the handle to the released position, Pump 5-7 times, Tighten the handle to the lift position and Pump to you get full extension, Release.. If you dont have plenty of oil in the resevoir to get to full extension without pumping air into the system you are wasting your time.