HF hydraulic press problem

[green-thumbs]

HF 12 ton hydraulic jack in press feels soggy…leak under pressure…any thoughts on how to
trouble shoot and repair…out of warranty…never abused.
Louis
Useful tool..hate to hang an out of service tag on it

[dmbono]

might need an O ring on the pump piston?

[Michael Anfossi]

Soggy would mean air in system. Leak would mean a bad seal somewhere. Bad seal allows oil to leak out and air to leak in

[jeff-register]

Louis,
These guys have it right except O-ring density problems. As the piston travels in the bore the o ring is to stay in place. With the wrong density the o-ring will roll in the bore dumping fluid as it travels & sucking in air.
Another problem I have seen is the flex hoses start to fail & tiny pieces of the inside of the hose get into the valve body & make things not function as the tiny chunks hang up everything. Feels like fine sandy grit in the oil. Check it before you run not true & damage the cylinder or piston. See if you are sucking oil from a leaking fitting too. Take it apart, A guy like you will find it easy.
Jeff

[green-thumbs]

I doubt if it is a wear issue…press has not been abused…no hoses just a bottle jack that just seems soggy and not exerting full force. Never opened up a jack…looked on line for helpful hints for HF press service…not found at this point. Maybe I should contact HF to see if they
have anything to say.
Louis

[Mumbles]

There should be a small screw or rubber plug on the side of the jack body about half way up. This is the fill hole for the jack oil or ATF you’re using.

[jeff-register]

Louis,
Maybe it sat upside down & started foaming. Air is compressable, not oil. I used ATF in my bottle jack. If it was dirty maybe some dirt got inside & "sanded" the seals. Dig around on the web, I found places here in Phx that had new seals for old tables. Warning though, If it has any runout the new seals will not help for very long. I rebuilt a pump for a table & once they held it at deadhead the seals let go. Take it apart with your spanner tool & hone with a brake wheel cylinder tool, then look for flat spots. I believe it is full of foam for some reason to be spongey.

[green-thumbs]

Never been upside down since I assembled (several years)
My bet is either some sort of seal/ O ring failure
or more likely the on/off screw seat is not sealing.
Before I go at it I would like to know what I am getting into….I am pretty good at making simple problem complex or fixing what isn’t broke until it is.
U Tube video no help…old computer/software does not play.
I have a backlog of different projects aside from outboards now that Spring has arrived.
No point in taking it apart until I know what to do and how…repair kit on standby too.
Don’t know a thing about hydralic jack repair but once I am up to speed I may have others
that need a look/see to get them right.
Louis
Mowed lawn 1st time yesterday and noted lawnmower drive is weak or not working
so another project…research says belt and two pulleys …common issue with make/model
Everytime I turn around more to do. Snowblower is on repair or replace list too.

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