Chamberlain 3380.... not B

You can do a quick check by plugging a pressure gauge into a remote coupler, set engine to rated speed and move the control lever, while listening for the relief valve to blow. If the relief valve is in good condition, it should make a click sound as it opens, followed by a hiss. Check your pressure. If your can't hear the relief, you most likely have an internal leak (valves, piping, etc) or a bad pump. If you hear the relief, and get a low pressure reading, it is a bad relief (broken/weak spring, worn seat, etc). Test the system twice, once while cold, and again after the system is at operating temp. You can perform the same test on the lift arms by fitting the gauge to an external tapping/port, chaining the lift arms to the rear axle and raising the arms. Generally, if the hydraulics become worse as the machine heats up, it is the pump. One can also get a $20 usb camera and stick it into the filler hole and have a look inside the unit for leaks. As for new pumps, I have seen newer pumps, using adapter plates and couplings, fitted with a bit of imagination.

Engine oil can be used in most systems , provided there are no friction units such as wet brakes and clutches. A surprising amount of hydraulic systems in new equipment use engine oil, typically 10w30, albeit with friction modifier and anti cavitation additives. However any good quality oil should be suitable for the older systems. I would stay away for gear oil as a temporary fix, as cold mornings can lead to a cracked pump, however some commercially available oil stabilisers, that make the oil tacky, can be of some assistance.

I hopes some of this helps.

Oh Wise World Of Knowledge, thankyou for your advice....
Plugged the ram back into the scari this afternoon and it lifted up like a bought one

your dont no what this go's up to a knob behind the seat and it controls how fast the linkage drops wind it or out

That makes sense, it does not seem to be connected to the remote, as I gave it a fiddle when all else had given up. .

thanks for your help


/me

that broken shaft is a selector valve dont know what it does

dont settle for just being GOOD Paul.... staying up to 2am to solve my problems and with pictures... that rates as awesome.

thanks mate... will put a bundy in frige for ya...

That lever is the selector from 3pl to remotes, someone has stretched it into the cab, but now its busted.. still works.

/me

An now I have had a better flick through the info you sent me, my 3380 is the earliest version with a single hyydaulic gear pump, but two systems, one runs the Power Shift and PTO, the other runs the Power Steering, 3pl and Remote Hydraulics. (later serials had a Dual pump... I thought it meant two pumps in my tractor but can only find one in any drawing)
The terminolgy is "Open Centre Variable Pressure... Oil is constantly being pumped even when demand ... stops
Open Centre means oil flows through the control valves ... when in their neutral position.
Variable pressure means the hydraulic system oil pressure increases with demand and is relieved back to the reservoir when it reaches the set relief pressure."

It would be nice if A/. I could find the relief valve and
B/. its was a cheap and easy fix to my problem.


what does Pilot operated mean for a presure relief valve...

I shall read on.

/me

Pilot operated means that another hydraulic circuit operates it.

I only know of the 4080 so yours maybe diffrent, if your steeing is light all the time I think the pump is in fair shape, the power steering is feed from a prioity valve on the back of the pump so this could be playing up, on mine there is a strainer on the return line in the bottom of the tank this maybe blocked, if the pump is ok then oil grade will only affect speed if it's not ok then run heavier grade, to get you by, the relief valve IS PILOT, what this means is don't mess with it unless you have a drawing, if you put it back together the way you think it should go then fist time you over pressure you will blow the pump apart I do know this first hand, if you carn't find a drawing then I will see what I can do, the power shift/high low is it's own thing filled though a round hole in the floor between your feet with ATF to the dipstick level, the red light comes on with low oil flow, on a old tractor I would not worry about it coming on at idle, there is a return flow filter under the round cover on the bottom if you change this the the light on the dash will only come on when the oil is really hot, the filter change will also fix the oil leaks around the linkage enteys as the blocked filter will pressurise the cavaity behind that cover, I have not been able to find the right filter so I just run a paper deisel filter of the same size, seems to work, when the oil starts to seep out the linkages I change it.

The handle maybe to operate the linkage when attaching to linkage only guessing mine has after market linkage.

If your transmission pressure light is flickering at idle, I would consider the pump as you have a problem with two separate systems served by the same pump. Bear in mind that the transmission/PTO circuits generally operate at a couple of hundred psi, verses the steering and 3pt at 2-3000 psi. It would pay to check the transmission filter, drain bungs, inspection plates, etc for signs of metal shavings, for if the pump has experienced a failure, as opposed to being just worn out, it could be filling the entire system with debris and wearing every bearing and friction surface in the machine. And to make matters worse, some tractors have a filter bypass valve which, when the filter blocks up with metal, the valve opens and allows dirty oil to flow through the system. I have seen many John Deeres scrapped, or have repairs costing tens of thousands because of this feature. I am not sure if Chamberlains use this design or not.

A pilot operated relief can control the system working pressure. In its simplest form, the pilot and main circuit work on a single spool, with the main trying to open the spool and relieve to sump and the pilot trying to close the spool. With no services being used, the main oil overpowers the pilot oil and relieves to sump. As the pressure drops the pilot has more now has more pressure and closes the valve. While working, these two actions will reach equilibrium and maintain a fairly constant pressure depending on the demand.