Harbor Freight 20 ton bottle jack

[cabranch47]

I haves a 20 ton HF jack that I think needs some fluid. It is very slow and does not feel like the pump is filling. What is the procedure for filling it and what do I use.

 

[dagofast]

There should be a fill port in the reservoir, probably a rubber plug. Use hydraulic oil. Small quantities are available at any auto parts store.

 

[BukitCase]

Agreed; also, those rubber plugs are usually a ***** to get out.

Actual procedure I use -

1 Open the release valve, stand the jack vertically (base down), push the ram fully back into the jack body.

2 When adding hydraulic fluid, it's MUCH easier to do if you use a hypodermic syringe - insert syringe about 1/2" into the fill hole, add SLOWLY til fluid just starts to seep back OUT of the hole.

3 Then operate the pump with the release valve OPEN for a few strokes to get rid of any air bubbles.

4 Then close the release and pump it up. Release it slowly and let/help it close - if/when fluid comes out the fill hole, LET IT -

5 clean up, replace plug, done.

Most jacks have the fill hole on the OPPOSITE side of the cylinder from the pump; they will (usually) let you use the jack on its SIDE if you have the pump BELOW the cylinder. Otherwise you'll get air into the cylinder and will need to repeat steps 3 and 4.

HTH... Steve

 

[cabranch47]

Thanks for the replies. I don't find a fill port on the reservoir. Would there be another option?

 

[Professional Tool User]

You sure there isn't a rubber plug or something you can take off?

 

[bri_man57]

FYI that plug might be painted over on a Harbor Freight jack lol.

 

[esvee]

It may move slower than you think it should. The speed shown in this video is perfectly normal for a bottle jack:

 

[dagofast]

Thanks for the replies. I don't find a fill port on the reservoir. Would there be another option?

It's there. It may be painted over. But it's there.
From the HF website: https://manuals.harborfreight.com/manuals/66000-66999/66482.pdf

 

[Odd-job]

The bottle jack is slllooooww. This is the reason why everyone with the 20 ton press upgrades to the air powered version.

 

[demarpaint]

I have one, it works flawlessly, but slow. Some need to be bled out of the box. The fill hole should be on the left side of the jack if you're looking at the release valve, near the mid point of the jack. It's painted over. @dagofast beat me to it, check out the online owner's manual. https://manuals.harborfreight.com/manuals/66000-66999/66450.pdf

 

[cabranch47]

Thanks guys. I will check again for the fill plug, possibly overlooked it.

 

[sberry]

Sposed to use hyd jack oil, its slightly different than common hyd oil.