allis b 3pt

got a '40 B with hydraulics, tried to hook up 6 ft blade ,wont pick it up ,too big? I know light duty tractor may a 4 or 5ft? system works good with nothing on it ,thinking just to heavy, Thoughts?

here is a picture off the NET of a B with an aftermarket hitch lifting a Disc... Dont know if he has one or two cylinders ........ but it shows it can be done...

its got one small ram, trouble getting picture to load,just need small blade to level roads in woods and scrape the drive once in awhile

blade is quite heavy,bought this 3 point of tractor at implement store, ram is mounted more vertical and pushes up on rock shaft bracket, will get daughter to help with picture upload and will be easier to see the configuration and ram , thanks for the replies thus far

i am building one right now for my c ,mostly biulding it like the the ones for sale but i am useing the two little lift cylinders hoping it can lift a 50 gallon spray rig i have the two engine side wieghts for mine

there is a 1 inch pipe plug by your left foot to fill the transmission and hydraulics.. make sure the oil is up to the bottom of the threaded plug .... If the oil looks like crap, there are three  1/2 inch pipe plugs on the bottom of the transmission, differential and PTO housings that you can drain and refill... Holds about 8 quarts.. Should by 20 wt, or universal tractor fluid or hy/ trans fluid, or ISO 32  or 46 hydraulic oil... etc.

Yes, on a B the pto must be on or engaged so that it is turning for the hydraulic pump to operate.

I just saw you said lift was jerky when lifting with no load on it.
I’ve seen that and sounds like a plunger inside the pump is sticking and not pumping properly, if it’s full of good clean fluid.   
Since it’s jerking with no load, I’d make sure it is full of fluid and pull the pump and inspect the plungers on the pump and the cam lobes on the pto shaft for wear. The pump comes off easily and quickly and you can buy or make a new gasket to reinstall pump.   
Could be air in system, but everyone I’ve messed with the air worked it’s way out after a little use and warming up.
I’d guess pump plunger problem that needs to be addressed, whether it picks that blade up or not after repair.   
Good luck, keep us informed.

Steve,
That’s a good idea using a test gauge.   

 if i move lower shock mount out towards end of drawbar in picture ,will that get me a little more push for something heavier?

Edited by steve(ill) - 18 May 2022 at 10:49pm

The B/C pump is a 2 plunger setup with double lobes for each plunger. Being a plunger pump, it is inherently jerky. however if it it excessive probably the valves to one of the plungers are not seating properly. 

if your blade is TOO HEAVY, you should hear the valve going over RELIEF pressure as you pull up on the handle, and the blade does not lift............. you could try to manually lift the back of the blade while someone is using the hydraulics... and see if you are WAY OFF, or just need a little more lift force.

Going from 2400 psi to 3200 psi  would be 30% MORE LIFT... That might be enough to move the blade...   There is a procedure to  PUNCH A PLUG  in the valve to SET the pressure.. That could be all it needs... But a disassembly / clean/ reset is not a bad idea.  Something made it DROP from 3200 down to 2400.... could be some WEAR.

Edited by steve(ill) - 21 May 2022 at 9:39pm

The implement does stay up with no problem, also i did move the stabilizers between the upper and lower lift arms . you can see in picture i posted there was a lot of threads exposed ,arms are more parellel to each other now, seemed to help. i can try your FIX tomorrow after work, thanks a bunch