New BH76A.Hydralic problem

Tarmy

Well-known member
Lifetime Member

Equipment
L2800, BH76A, FEL,box scraper
Nov 17, 2009
462
363
63
Lake Almanor, Ca
I just got a new BH76A put on my 2008 L2800 and everything works fine...EXCEPT some of the hydralic rams at first didn't function...we traced that to comtaminants(paint) in the system and cleaned the pressure relief vales...and that appears to have fixed some of the problem...now I have weak performance (contracting) two or the boom cylinders...the main and the dipper stick...everything else has consistent in/out power...just when I pick up a 100 pound rock or something...I can't get it to retract/lift it up...anyone got ideas/suggestions?
 

eserv

Well-known member

Equipment
BX24, A1000 Kubota Generator
May 27, 2009
2,140
139
63
Hardisty, Alberta
You will need to do a system pressure test. It should be in warranty! I'd get it to a Kubota dealer and get it completely flushed out preferably on someone else's tractor. I'm not sure what it should lift directly with the boom like that but 100 lbs sounds pretty weak .( the cylinder has a lot less area on retract than extend) We have sold some of these and have had zero complains!
Ed
 

Tarmy

Well-known member
Lifetime Member

Equipment
L2800, BH76A, FEL,box scraper
Nov 17, 2009
462
363
63
Lake Almanor, Ca
That is my problem...my new setup is nowhere near a dealer....so I am trying to figure out a way to service it myself...not to mention...I want to learn as much as I can from this experience so I don't have to always rely on the dealers...Transportation is a big problem in my situation...I appreciate your comment...as I did not know there is a difference in the extension/retraction force of the hydraulic rams....I am sure it is under warranty..as the tractor still is also...thanks
 

eserv

Well-known member

Equipment
BX24, A1000 Kubota Generator
May 27, 2009
2,140
139
63
Hardisty, Alberta
Get yourself a pressure guage that reads at least 2500# and plumb it into the system before the oil gets to the control valve. then run the tractor and extend and retract each function to the end and note the pressure at the end of stroke. It should be 2347# with the tractor running above idle ( doesn't have to be exactly that!) If the pressure is less on any function you have a leak in that function. If the pressure is right then that is all she's gonna lift! Kubota rate that BH at 2097# dipper digging force but it isn't going to lift near that.
Warranty is only one year on attachments here in Canada, US is probably the same so get it working right before it's off warranty!

Ed
 

Tarmy

Well-known member
Lifetime Member

Equipment
L2800, BH76A, FEL,box scraper
Nov 17, 2009
462
363
63
Lake Almanor, Ca
Thanks...which side of the control valve...the supply line to the individual ram (I assume) or both sides...one after the other...the see if the valve too could be an issue? If there is a leak in any function...what causes that...faulty part?
 

eserv

Well-known member

Equipment
BX24, A1000 Kubota Generator
May 27, 2009
2,140
139
63
Hardisty, Alberta
I would plum into the fitting on the control valve where the oil comes from the tractor. That is the hose that goes all the way to the loader valve. ( at least it is when I set them up!) Then operate each function one at a time and note the pressure when it is at the end of the stroke. If all are low your relief valve is set to low on the control valve if just one is low then that cylinder is probably leaking (unlikely on a new unit but then ,it was contaminated!)
Ed