the prentice F loader we have seems to lack power. you have to rev truck up alot i know it's not brand new but it wont lift 1000lbs right next to truck. what is the recommended pump volume and psi for a loader anyone know heres a pic of it
(https://forestryforum.com/gallery/albums/userpics/25890/3496/Picture.jpg)
What psi do you have now?
That would be a good place to start checking it out.
Does loader settle when raised and valve in neutral? If it does could be a blown
piston seal in Cyl. Pump should put out enough pressure to pop relief valve when cylinders hit there end of stroke and enough flow to move loader at a decent speed.
Jim
how fast are you spinning the motor? check with oliver stores, they should have all the specs.
sorry I'll rephrase the ? the boom has no power the grapple, rotator, dipstick, stabilizers and swing are fine
If everything else works fine, and the boom cylinder doesn't leak oil, I'd say it has to be in the valve?
If it worked fine and now you have no power I would start at the valve also. Especially if all the other systems are doing okay. Does it have an overload for each spool? How long since you changed something on this circuit?
put a tee in one of the boom cylinder lines and use a 3000 lb gauge to check the pressure . a good bet would be to pull the relief valve for that circuit and see if it has something holding it open.my loader has a circuit relief for the boom lift it is in the valve body and has the pressure setting stamped on the top of it
another thought if this happened gradually it probably is a pump or cylinder problemm if it happened quickly it almost always is a valve or relief problem
to answer your pump question...25gpm 2100psi dose the oil get hot? if the pump is worn out the oil slips by the gears and that makes even more heat. that is one old loader....... from the 60's??
I had the same problem with my Prentice 110. I switched the lines at the control valve from the non-functional cylinder to another valve and it worked fine. It confirmed that the problem was with the original valve. I have not gotten around to repairing the valve as yet since I am not using the loader at this time.
Sparky
There's a good chance that the seals on the main boom cylinder are worn and the fluid just blows by as you try to lift the boom. If your stick boom cylinder works ok that where I would start. Good luck Bill
they usualu use a piggy back pump setup 2 pumps in tamdem sould make 50gpm 1 side usualy runs the main boom and swing the other handles the stick and graple/rotor the lift pump side usualy goes bad first but you can rebuild the whole pump for 3-400 bucks
Quote from: forestry mick on September 24, 2011, 06:05:43 PM
they usualu use a piggy back pump setup 2 pumps in tamdem sould make 50gpm 1 side usualy runs the main boom and swing the other handles the stick and graple/rotor the lift pump side usualy goes bad first but you can rebuild the whole pump for 3-400 bucks
the tamdem pumps werent used until the 110 came out. if the packing is leaking inside the cyl will settle down with the boom in the air. valve in netural. a valve leaking past the spool can act the same. the valves are not rebuildeable there are o rings that seal any leakage between the spool and the valve body but thats there only job . dirt or sumpin under the seat of a main releif or circit relief valve. dose the valve stick when the oil gets hot?
A fine example of what makes this site the one to go to. I learn something every time I open it up. Great bunch of guys. Chuck
first two things to check.
Pressure check to start,
Relief valve O rings and springs, if this gets the pressure to a good range you are done. If not check inner pump seals and gears, valve body seals cylinder seals, if they are wore out you can rebuild it or replace as required. on the pump I recommend replace it if the gears are worn as the body will be worn enough to make a rebuild only a temp fix at best.
For some reason i only saw 3 replies on this post when i first opened it a few minutes ago. when i posted then i saw all the rest of them. So i didn't have all the info when I typed this reply.
I think the rest of the replies address the possible problems pretty good.
we did have a loader like that years ago, must have ben modded with the 110 pump at some point
Quote from: forestry mick on September 24, 2011, 11:35:00 PM
we did have a loader like that years ago, must have ben modded with the 110 pump at some point
if so it would also have to have a midsection in the valve bank. one for each side of the pump
well I had a chance to look at somethings the boom does drop by itself but I'll can't worry about it right now just lost water pump on the skidder friday
I feel your pain HuZzey, with used equipment like ours there is always a priority repair to be done. Hang in there and have a safe day.
I'm hangin last month I blew another planetary also all I did was backup to hook some trees on and pop locked the left front wheel up had to take it off in the woods to drive it out. broke every planet gear and all the teeth on the drive gear were worn off smooth but for a 1/4" on one edge.