Fixing Harbor Freight Lift

[ryanDeVries]

Searching the forum I could not find anyone talking about when things go wrong with the Harbor Freight Motorcycle lift.

Last fall I had a puddle of hydraulic fluid under mine and now the unit will only go halfway up. When I open the fill valve it is full to the brim with fluid. I have tried holding the release pedal and pumping to bleed air out with no results. Do I have to remove the pump and change the orientation or something?

[makinsmoke]

Ryan,
It's either mechanical or hydraulic. If you had
a mechanical bind while lifting you could have
damaged a seal. Scoring of the ram can allow
fluid bypass internally or externally. You need to
find out where the fluid came from.

You might disconnect the ram and see if you
have free travel of the lift in both directions.
Then see if you have full travel of the ram
while disconnected.

Feels like to me you have fluid bypassing
somewhere before you get full travel.

[Fred_V]

I've had the same issue with my 500# lift cart. How can there be fluid on the floor and the cyl. be still full? Running it down and up a couple of times seems to get it working again.

[steamin10]

I dunno, but all the crossed beam lifts I have worked with do not like to be stored while partly extended or more. The cykubder seaks tebd ti keaj diwn and cause ribkems

Really?

The cylinder tends to leak down and cause problems. As a matter of course either install struts or blocks to take the weight , or collapse your cylinder for storage, and raise it back up when needed. I think even an overnight pause would warrant such a reset. Just my nickles worth.

[shayloco]

The cylinder tends to leak down and cause problems. As a matter of course either install struts or blocks to take the weight , or collapse your cylinder for storage, and raise it back up when needed. I think even an overnight pause would warrant such a reset.

The HF motorcycle lift table I have came with a bar that is slipped through the lifting arms to hold them at height without strain on the cylinder.

[steamin10]

Thanks for clearing that detail up. It adds emphasis to my , 'I dunno'.

[ryanDeVries]

So I was able to root cause my harbor freight motorcycle lift issue.
1) For two years I have been storing the lift in a up position, sometimes with a railcar on it and no bar to release the pressure.
2) The fluid leaked out of the pump assembly not the ram.
3) The pump has score marks, see picture below.
4) The O-ring in the pump is chewed up.


This picture I am trying to show the damage on the plunger, at the tip straight at the camera. There is matching marks on the cylinder.

Now I do not have a lathe, else I would make two new of these parts, replace the O ring and be on my merry way. The guy on this youtube video replaced the pump. https://www.youtube.com/watch?v=wxj2HcG52cE This may be a good option. Buy a $20 pump and re-engineer lever system. Or I could replace with a electric or air powered pump. I do not have air in my garage so that is out. And I am not in favor of the risk of running over a electric cord. I could go battery powered? I have not decided yet.

Also many people talk about how the fill valve looks full of fluid. The screw at the bottom is not the fill valve. That is access to one of the check valves. The fill hole is the rubber bung about 2/3 of the way up the cylinder. Now most bottle jack instructions online state to fill to the lip while the jack is standing on the base. I somehow doubt this jack is any different. Filling it while it is sideways will overfill the reservoir.


This image is showing the five parts in the overflow safety valve. A small ball, a plunger, spring, set screw, closure cap. Not quite sure how i am going to reset this valve properly.
I
I definitely had a lot of air in the system as the remaining fluid starting foaming and bubbling. I drained out all the fluid and used an air hose at 10lbs of air to blow out the old fluid as I plan to put new in, now the cylinder is set in a position so it can drain overnight.

[hammermill]

polish it all up and get the scrap out of the piston area and with a new o ring you may be good to go

[GooseOrBust]

Like hammermill said, I'd just clean it up, put in a new "O" ring and store it properly. Chances are, it will last a few more years.

Then, on to the next project.

You can't expect too much from HF.

[Fred_V]

Can you get replacement cylinders from them?

[ryanDeVries]

A replacement bottle jack assembly is available from Harbor Freight for $43 plus shipping. It will take 6 to 8 weeks for the replacement parts to arrive. While I could have gotten a replacement pump from another jack that would have lead to the need to replace the pumping levers. I ordered the replacement jack assembly for the long term solution and for the short term I have polished the ram and the bore of the pump with wet dry sand paper. There is still evidence of the scoring in the bore so I do not know how long my fix will last.

If I had a lathe it would be a simple matter to make the two damaged parts myself.

Look closely at the pictures for the lift as they did a redesign and kept the same overall part number. The 2016 picture shows a jack held by bars out the side and the pump and release mechanism out the bottom. The older design, that I have has cast ears out the bottom and the pump parts are in the typical beside the bottle jack location.

[xo18thfa]

I had the same thing happen to mine. Fiddled around with it, tried all the fixes. Ended up hauling it to the recycle. Some times life is too short to mess with things like that.