This is a model 26 B/H mounted on my 450 crawler.
This is a single ram which will 'leakdown' in about 8-10 minutes, tractor running.
Also, there is an intermitant problem w/ the same ram. Most of the time, there isn't enough force to lift the rear of the machine off of the ground, and sometimes there is.
The manual has a proceedure to test the hyd rams on the bucket/blade, for internal seal leaks.

Collapse the ram, disconnect the upper line, collapse again. if the disconnected line leaks a considerable amount of fluid, then the internal seals need replacing.

Q) can this proceedure be performed on any Hyd cyl. (the BOOM cyl)? I am good w/ my wrenches, is replacing the inner seals a job for others only, or is it a straight forward proceedure?

I also am suspecting the relief valve and possably the control valves. There is no exterior leakage on any of the cylinders, and the fluid level is correct. Filters have been changed too.

All of your ideas are welcome. I ahve been turnning wrenches professionally for over 30 years, but this is my first Hyd Cyl.

P. S. I am not as flexable as I once was. I perffer NOT to remove any componant than what is necessary. LOL!

Thankyou again, and please give your $.02...
steve n carolyn

sounds like your bypass is in the valve chest itself if it has no exterior leakage. worth a try to replace the parts yourself if it don't work then take to a repairman that does it for a living he can correct anything you may have done wrong if he knows what hes doing if not you don't need him anyway.

Thanks Bill, I'll be looking at it closer this monday, The book shows 2 different versions of a bypass valve.
Q) By calling it a "bypass" valve, Can it also be referred to as a "relief" valve?

I was looking at a "blow-up" diagram of this 'valve chest'. Aside from any worn items, it looked like a bunch of 'O' rings, not to difficult.

Don't know about the Hyd ram....sl

usually about all you will find there is O-rings or a sold rubber block or seals to stop the fluid from going where its not supposed to be unless that selection is made.
What I meant by bypass is usually a seal or O-ring that is letting fluid go by when is not supposed to.
Relief valves are for another purpose but self explanitory also.
If you take it apart look for stretched or torn O-rings and seals. Anything other then to take something apart don't turn or your pressure will go up or down. The only thing you need to mess with is the little valves sticking up attached to a lever. Some wear on this shaft is tolerable sna usually not a problem unless there is lots of scoring on the walls.
good luck

Bill wrote,

"The only thing you need to mess with is the little valves sticking up attached to a lever."

Bill, would these be the 'poppett valves'?

thanks, sl

I don't know what they are called but the ones that attach to the levers are the ones you will have to check to see if the seals/ O-rings are damaged.

Thanks Bill.
steve