# Ford 540 Loader no 3 point hydraulic power



## DanC (Oct 4, 2013)

I had this posted in the repair forum and moved on Big T's suggestion

I have a 1979 Ford 540 Loader with 3 point and PTO. The Box Scraper controls were always slow especially when cold then one day nothing. Changed the rear end/hydraulic fluid and took the pump (engine mounted and gear driven off the cam) to the dealer who found a broken pin and rebuilt the pump. Re-installed and still no power. Put a gauge on the pump test plug and read 0 psi. Put a funnel under the pump with the plug out and it would pump enough oil to fill the funnel in about 10 seconds, it flowed out like poured out of an oil bottle but didn't spray. I was going to replace the pressure relief valve to see if that was the problem but was quoted $300, I removed it and there was no obvious damage. I am trying not to haul the 50 miles to the dealer that rebuilt the pump. Any suggestions appreciated.

Thanks Dan


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## DanC (Oct 4, 2013)

From Big T

"Howdy Dan,
I never go to the repairs section, so I didn't see your post until I got your message. And it's been awhile since I've been on the computer. Been out hunting. 

It's best to post your Ford 540 tractor problems on the Ford/New Holland board, as there are a number of guys there that can respond to your questions. 

Is your fluid from the pump aerated? Do you see any bubbles in the fluid when you test it? If you have aerated fluid you have a suction leak. There are o-ring seals on each end of the suction line (the bigger of the two lines, about 1" diameter). To fix this, simply replace the O-rings. You can also put caulk sealer at the connection points to see if this is your problem. You may also have a crack in the suction in the suction line - look it over the entire length for oil seepage. 

If no aerated fluid, you may have a plugged suction screen. This screen is at the bottom of the reservoir. Have to pull the lift cover and other parts to get to it. As a temporary measure, You can use compressed air to blow out the screen. Remove the rear end filler cap before you do this so you don't damage any seals internally. Remove the suction line and blow back into the reservoir. Drain the fluid first, so you don't make a mess.

Good Luck. If the pump is not putting out, it has to be one of the above. Either that or your pump rebuild is bad. Please post on the Ford New Holland board so more Ford people see it."

Big T. When I start up with the pump plug out it takes a few seconds but then I get oil that looks just like you are pouring out of the bottle, no air bubbles and low pressure. I see no signs of any leaks in the suction line. When I changed the oil I used compressed air at the pump end of the suction line and refilled the line from the top and got flow thru to the drain plug. When I talked to the dealer he said he never found the part of the pin that broke off, is it possible it could get to the pressure relief valve and cause a problem? Attached the dealer's photo's of the pump, second photo at about one o'clock is the broken/missing pin. Would like to get as much feed back as possible before calling them about the rebuild.


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## Ed_F (Jun 18, 2013)

Your tractor's pump is rated at 5.6 GPM according to tractordata.com. I assume that is at rated engine RPM, which for a 201 engine is probably about 1800 RPM. Did you have the engine idling when you checked flow from the pump? 

You can put a hose barb in that plug hole on the pump, and run a hose back to the hydraulic oil filler port on the hydraulic sump and see if it pumps oil through when you start it. Clear plastic tubing should suffice, that way you can see if there are any bubbles in the fluid. 

You can also gauge flow through the hose into a clean bucket. Mark a clean 5 gallon bucket for a known volume (i.e., 1 gallon) and see how many seconds it takes to reach the mark. Engine RPM ~1800 . Calculate the equivalent GPM output of the pump.

The missing pin could be anywhere, but Murphy's Law suggests it will be stuck in the flow control valve, or pressure relief valve, or maybe in the unloader valve. How big is the missing pin (approximate dimensions).

What oil are you using in the rear differential? Universal Tractor Fluid (UTF) equivalent to Ford 134D specification?


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## Big_T (Dec 1, 2011)

See item #1 on the attached diagram. It is possible that the flow control valve is dumping most of the flow back to sump and resulting in no hydraulic pressure.

Does the flow control spool move freely?


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## DanC (Oct 4, 2013)

Ed .... I filled with the specified hydraulic fluid. I will rig a hose to check the flow this week end.

Big T ... If you are talking about the plastic speed control knob marked "F" and "S" yes it turns free but I recall times that it did not.

Thanks Dan


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## DanC (Oct 4, 2013)

Ed .. I would guess the pin is about 1/8" diameter, I only saw the picture above and would say the pump housing shown is about 5" diameter.

thanks


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## DanC (Oct 4, 2013)

I put a barbed X thread fitting with a clear hose in place of the pump plug and got about 1 GPM with lots of air bubbles in the line. I am thinking I may have dislocated the "O" ring on the pump suction when install the pump, the bottom end of the suction line was never removed and there are no signs of leaks there. Thinking if there was a problem with the pump rebuild it wouldn't explain the air? So is it time to pull the pump and check the "O" ring?


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## Ed_F (Jun 18, 2013)

Try putting some sealer or caulk on the connections on both ends of the suction line to provide backup for the O-rings. There is a small annular ring around the tube that the o-ring seals. 

One other possibility. I know that you said that you filled it with the specified fluid, but are you certain that you filled the hydraulic reservoir (rear differential reservoir)? Filled it through the opening on top of the rear end until fluid came out of the fluid level check port. If it's empty, you will suck air from the reservoir.


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## DanC (Oct 4, 2013)

Thanks Ed ...... yes filled the rear end thru the plug next to the top of the differential. The local auto store matched the fluid number with "NAPA Premium Tractor Hydraulic and Transmission Fluid for Wet Brakes", it notes under matching fluids for New Holland M2C134 on the drum. My Ford Manual calls for M2C53A and notes the quantity as 48.3 Quarts for "Independent PTO". I drained completely and added 48 quarts new fluid. I will have a chance today to pull the level plug and top off if needed. I will also seal the suction connections to see if that helps.


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## DanC (Oct 4, 2013)

In case anyone is interested I ended up taking it in to the shop. They removed the head unit from the rear end and found a plugged screen on the return line. Cleaned and flushed all and now the box operates stronger and faster than ever. Thanks again


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