How to refill /prime a floor jack?

rrman61 · Jan 29, 2021

What looks like the reservoir is mid piston capped with a rubber plug.is there a process to fill/prime it?and with what?hyd.fluid,atf?

jd man wis · Jan 29, 2021

Yes that's were you fill it. Iv been using brake fluid and seems to work better.

Frank(Mi.) · Jan 29, 2021

I used the Lucas hydraulic sealer when I filled mine. Works good so far...

old · Jan 29, 2021

Yes that is where you fill it. Have it all the way down. Fill it as full as you can then put the plug back in. I use ATF but there is a hyd jack oil made just for that

used red MN · Jan 29, 2021

I would strongly suggest to take the use of brake fluid as an experimental approach. Jack oil and brake fluid com from a quite different base. Buy some hydraulic jack oil.

Denny K · Jan 29, 2021

I have a Walker floor jack a guy gave me because he had filled it with oil (it Leaked a fair amount) and couldnt get to prime.
I took it home and in the process of picking it up, I tried to grab the rear axle and missed and grabbed the lift arms. The release valve must have been open some because after I set it down and closed the valve it pumped right up. It must have sucked some oil into the valve area. I did put a kit in it later to cure the leak. This was about 40 years ago and it still works.

Hobo,NC · Jan 29, 2021

Prime, open the release valve and pump that will bleed the air out of the it. I make sure they are vented when I prime them either by leaving the fill plug out of loose are taking the vent plug out. If its not vented the reservoir will get air bound from trapped air... If you ever pump a jack and the piston is jumpy are spongy its fighting trapped air under pressure on top of the oil in the reservoir.

Oil, I use tractor hydraulic fluid why cuzz I got a bunch of it. If its good enough for tractor hydraulics its gotta be good for my jacks... : ) YMMV

chcase · Jan 29, 2021

JD man As stated using brake fluid in a jack doesn't work well.

jd man wis · Jan 29, 2021

Ok I will get some for the leaking floor jack. I just use enf in it so the jack would work so I don't think it hurt any and the bottle I had on the shelf was empty witch tells me that the younger boy was here and it's like the milk jug just put it back when empty. Thanks for the info guys.

Steve@Advance · Jan 29, 2021

My jack can only be filled with the jack up, as you can not get to the plug with it down.

But filling it full in the up position will over fill it.

What I do is put in a guestamated amount, let it down with the plug out. That pushes out the excess. If none comes out add a little more, and let it down. Then jack it back up enough to get the plug in.

It will self prime and clear any air with a couple of raise and lower cycles.

Any light oil will work. Do not use brake fluid!!!

How to refill /prime a floor jack?

rrman61

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jd man wis

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Frank(Mi.)

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old

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used red MN

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Denny K

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Hobo,NC

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chcase

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jd man wis

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Steve@Advance

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