Ford 555 Power Reverser Success – Kinda

This tractor has not been very well maintained in the past. When I first got it the oil in the transmission was milky white and laden with water. It was drained and replaced with fresh oil, but the reverser would not engage.

Initially I placed a gauge on the test port located inside the cover plate on the bottom of the bellhousing. The gauge would only flutter between 0 – 20 PSI. Not wanting to break apart the tractor, I sought a way to do the diagnosis. After studying the service manual, I discovered that access to the suction/inlet passage and sump screen could be made through a pipe plug that was in a cross-drilled hole. I cannibalized an air regulator/filter assembly by removing the filter element, and used it as a canister to hold kerosene. I improvised some tubing to connect to the ½” NPT threaded port so that kerosene and air could be blown backwards through the pickup screen.

After draining the transmission of its oil again, I blew the kerosene and air through the passages and out through the pickup screen. With great hopes, I jacked up the rear of the tractor and placed on jack stands to allow the tires to spin freely if the shuttle engaged. Then I re-filled the transmission with the oil and performed a retest. Immediately the pressure jumped to 110 PSI and the shuttle engaged as it should. with the transmission in gear, the wheels began spinning! Ah – success, but this was short lived. In about 5 minutes, the wheels would no longer spin, the pressure was fluttering around 20 PSI, and no oil was being returned to the transmission from the oil cooler circuit.

Not to allow this to defeat me, I went back to the service manual, studied the fluid circuits and came to the conclusion that the pump would not work intermittently, but had to be something else. Either the screen was re-clogging or the by-pass was stuck open. I ruled out the relief valve, because it had a one time allowed the pressure to go up to 110 PSI, and when the engine was raced allowed it to go to 160 PSI.

I went in through the inspect hole at the bottom and removed the hex head plug that captures the by-pass valve. When it was removed the compression spring holding the check ball was broken into 4 pieces, thus not holding the pressure high enough to push oil through the converter through the rest of the circuit. I went to my 40 year accumulation supply of springs and chose one that was close to size and put it in place. I’ll get a new one from Ford-New Holland later.

I went back to the transmission and reconnected the improvised canister and air line. While running the motor, I blew air backwards through the sump and immediately afterwards, the pressure climbed to 110 PSI and stayed. The reverser worked again, but after about 5 minutes it stopped. I blew air backwards again and it worked for a few minutes and stopped. Shutting off the engine, at this point I decided to drain the oil while blowing air backwards through the sump screen to keep the oil stirred while draining.

During draining, I noticed several lumps drop into the drain bucket. Further investigation showed that there was a mixture of masticated RTV, bits of plastic film, and rust flakes. These were being sucked to the screen, accumulating, and blocking it during operation. I plugged the transmission, blew kerosene and air backwards again through the sump screen and then continued to blow air to agitate the kerosene in the bottom of the transmission. Afterwards, I drained the kerosene while agitating and all kinds of crud came out with it.

I removed the shifter cover and placed a shop towel over the opening and poured the oil back into the transmission through the shop towel. Again, all kinds of crud were captured by the shop towel.

The engine was restarted, and this time with more lasting success. I ran the engine for nearly an hour with the transmission in gear and frequently reversing the direction to assure all was working OK. I allowed everything to come up to temperature, and made sure the cooling lines were getting warm to assure circulation.

I had come to the conclusion that I would drain the transmission and torque converter and replace all with new oil. Afterwards, pressure wash the outside and apply new paint before re-installing the loader and cab. The longer it ran the sweeter the engine ran. Then while running at about 2/3 throttle, a bang was heard and then a clatter – A THROWN ROD IN THE ENGINE. Now the engine won’t turn completely over. It stops with a hard metallic thud.

ON TO THE NEXT PROJECT! – an engine rebuilding. Anybody got a good Ford 201 diesel engine for sale?