700R4 Governor Malfunction/Replacement and Custom Pressure Gauge Installation...

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RanchWelder

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My 700R4 had to be replaced Feb 2021.
So I contacted a reputable builder and sent my money off for the down payment.
The lockdown caused major supply issues and it took until Dec 2021 to get my build. It came brand new, not rebuilt, with a new case and internals.

I requested the lock-up to be eliminated, so the connector never shorts out and the TV adjustment is not capable of causing the transmission to become unable of un-locking. My general usage is 10 miles to town and 10 miles back, for groceries and the mail. When I go off road, the trails demand slow driving anyways, in the Mountains of Montana.

Gas milage was secondary, mainly because my primary concern is NEVER having to worry the lock-up problems could EVER occur, while off road dozens of miles from help or home. We have had 12 inch snow falls in April, with below freezing temperatures in the Mountains, when it is 70 degrees and sun shining 18 miles away in the valley. Not being able to get out before the weather changes can become a rescue mission.

When I finally got my new transmission installed Dec 2021, the builder instructed me: the NON TV cable may or may not be required to tune the shift point. My experience, was shifting delays from 2-3 at around 38-55 mph. So I started to adjust right away and took up on the cable a little at a time and sure enough 2-3 started working well. 3-4 was consistent for a few days, then 3-4 started to screw up... so I took up a bit more and it got worse.

*** (Testing of these shift points and recalibrating was done, with less than hundreds of feet driven, not miles each test or adjustment).

So, around 3 weeks ago, the transmission started having trouble with shifting between 3-4 during routine driving. I was having to drop it into neutral at 55mph in order to over rev, just slightly for it to soft shift into 4th and complete my short drives.

The trans has less than 2000 miles and has only been driven 30 miles round trip, as the longest drive, in the past year.

So, I thought I'de start a thread and explain where I'm at, what the diagnosis was and the steps I'm taking to verify the pressure and shifting system.

*******************************************************************************

The first step, was to contact the Builder and get permission to verify some suggested pit falls and potential repairs or investigation which I may be able to perform myself, before complaining and having to send my unit back for an overhaul.

Very glad I called first.

I gave my details and explanation of the shifting, the adjustments made to the non-TV shifting cable, verified each adjustment and how it effected shift point to the builder.

The builder confirmed the shift cable was still required, based upon the 2-3 issues being resolved and that my experience with fixing minor shifting issues between 2-3rd, may have resulted in over adjustment and caused 3-4 to be slightly out of correct cable length, so...

I made small adjustments back to ALMOST, where I started and the result was not what was expected...

The 2-3 issue which should have been recreated did not turn up... and the torque converter was now shuddering when driving from a stop, shaking the exhaust more than the cam...

The truck is loud and the cam hits more than stock. This along with the racket my spark arrestors, made it tough to consider or identify the shudder, at first...

...so I started to read and learn what others had found when these things aligned...

The other issues was: The truck would stall, at idle, when I jumped out to open and close the cattle gates in -40 degree weather we had, few weeks back. This did not seem related and with the extreme temps, I really had no explaination, other than the usual water condensation frozen in the fuel tanks and lines or the transmission just being extremely cold.

My truck already has been modified with a 3-wire O2 sensor, using a 30a relay and Zener Diode with resistor, to protect for fly-back voltages. (That is another write up for another day).

The engine stalling at idle, turned out to be directly related.

********************************************************************************

After speaking with the builder, he authorized me to pull out the Governor and verify the springs and piston were working properly, and I'm very glad I did right away and not waiting for months to do this. He confirmed the issues I was having COULD be the Governor and they have been known to fail early on otherwise quality builds.

Here's a picture of the Governor:
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The diagram shows the small springs. My old transmission had the Governor still installed, so I pulled it out and compared it to my new unit.

Sure enough, the new unit was NOT plunging the Piston/Valve you see in the diagram and was seemingly stuck towards the gear, which is driven off the tail shaft of the 4x4 700R4. I had to twist it to pull it out, even though I had the transmission in neutral and the wheels blocked during removal on my truck.

Some of the threads I read at 3rdGen said to always use a new gear, when replacing these.

My old Governor was relatively new in it's rebuild life, before it burned 3-4 due to lock-up freezing.

I opted to push the pin, remove the gear from the bad unit and swap the springs the builder engineered into my transmission... You see the springs are and can be different. I wanted to make certain I used what my builder installed for both the re-springs and drive gear on the Governor being installed.

The springs are quite challenging to put back in. It took 2 thumbs and very careful positioning or they slip sideways and go flying across the room. You have to be very careful you do not stretch them, during the multple failed attempts, or damage them entirely. If you ruin them, they should not be reinstalled...

Re-installing the push pin, on the gear, was also very difficult. The urge to use a bigger hammer must be avoided.

The drive pin had to be pulled out and straightened then tapped into the proper direction 4 times, before I got it correct. It was not easy. The chance of accidentally hitting the gear and breaking it, was obvious. Carefully resting the shaft off the end of a 2x4, I was finally able to align, and replace the pin correctly. I found tapping the pin to align the opposite hole, by tapping left to right as the pin went in, finally worked. Slow taps, was the key.

I twisted the new Governor in and carefully replaced the seal and cap.

Be very careful to tap around the cover and use a large pin push tool around the cover, so as NOT to deform the center of the cap. If you beat in the center, you can drive the gear forward and ruin your gear, Not in far enough and you'll grind the end off the gear and allow the shaft to mis align, causing more valve movement, than should be allowed to occur. The governor can slam back and forth during driving, if the cover is not all the way seated and sealed.

The amount of fluid lost, was teaspoons, not quarts...

Now for the test drive...

***********************************************************************************************

Sure enough, the 2-3 shift issues came BACK!

Quick stop on the side of the road, a lil' bit more tension on the cable, wallah. 3-4 shifts were back...

I reported to the shop my findings and every detail of using the parts they engineered for expected results, the re-adjustments and the drive test results. The manager asked me to buy a pressure gauge, so we could confirm the pressure the transmission was shifting at now. So I started to design the parts for my new gauge, hoping to make it a permanent install.

Here's my parts:


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Since I already own an OTC cylinder pressure gauge, I am going to use the 300psi gauge, which is rated for wet use and save a few bucks over buying a specialty kit.

I wanted my installation to be permanent, with the option of driving with the gauges in the cockpit.

The pressure port used, is the 1/8" NPT test port on the case. It's located over the shift linkage, on the left hand case, if you are sitting in the driver's seat facing forward.
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This is a good picture, because it also show the governor cover, which may or may not have a flat o-ring seal under it. It also shows this case, which is different than the "K" case used on OEM 4x4 trucks. My new case looks like this picture. It is important to note, the case shown here does NOT have the 2dn, 3rd and 4th pressure ports cast into the casing... These would normally be located right next to the electrical connector, seen in under the number "5".

These ports, if you have them can be used for pressure testing as well.
However, since the unit I was shipped DOES NOT HAVE THEM, this instruction will focus on the circled port in this picture, as the only port available for testing.

*****************************************************************************

The youtube videos of expert transmission builders, seem to all show the builder, just hitting a hammer one good blow to knock the Governor cover off. I was a lil' bit more careful and tapped it off gently, since I do not have dozens laying around and did not want to distort the cap at all.

Reached the limit on files can be attached, so...

In the next post, I'll go over the parts I selected for the hard lines and fittings.
Hopefully, I'll be able to include the testing procedure the builder emailed to perform...

(I'm new here and... Several of the photo's used were from parts manufacture's and were searched with Royalty Free images, in the search bar... If I have to replace any pictures with my own, please let me know...)

It's really cold this week... -20.

I'll try to update as the lines and fittings are being installed, so detailed pictures go along with the story.

-Welder
 
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Tank6x2

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great information and write up bubba, a lot of detail! How’s this coming now?
 

Ricko1966

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Here's some 700r4 reading material. Not sure of how much of it I agree with but you all are free to read and make your own decisions
 

RanchWelder

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Well here's my DIY pressure test set...

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Installed this:

Allstar Performance ALL46310-72 72" 4 AN Braided Brake Line

Allstar Performance ALL50019 4 AN Male to 1/8 in NPT Male 90° Adapter, 4AN to 1/8"

JMCUHYD Hydraulic Ball Valve KHB 1/4" NPT 7250 PSI Shut-off High Pressure Ball Valve 1/4 Ball Valve (This had good reviews...)

Aeroquip FCM2721 Steel 1/8" Female Pipe To -04AN Male Adapter

Metalwork 304 Stainless Steel Pipe Fitting, 1/4" NPT Female x 1/8" NPT Male Reducing Adapter, 2 Pcs

U.S. Solid 304 Stainless Steel Hex Nipple, 6000 psi High Pressure Heavy Duty Pipe Fitting, 1/4" x 1/4" NPT Male Thread

I used a rubber grommet which just barely fit over the -4an brake line fittings and drilled an 11/16" hole into the tunnel, so the line can run behind my dash.
It can be removed and used for a number of things and gives me the option of routing under the rockers to the transmission, if required.
It will work for every other attachment of the pressure test system OTC provides for cylinder verification and the leak down test kit, (which I did not picture in this thread.)
Read the brake line is rated to exceed 1500 psi. Way more than a similar rubber braided line... The ball valve allows me to shut off the gauge so pressure is not on the valve when not being read. It was really handy to have it in my hand while driving, (the few days it was working...).

My pressure was average... in every gear...
When I tried to test it at WOT the engine just spun and pressure went to zero...

So contacted my builder and he said to swap the fluid, clean/inspect the pan...
Here's what was found:
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The filter is supposed to be yellow, the magnet is supposed to be flat and the pan fluid should be red, not dark Purple to Black.
The black on the bottom of the pan was stuck on the metal.

With 7 quarts of fluid strained through 3 x 600 micron strainers stacked on one another, and a new filter on month 4, I was able to drive 6 more months from install.

After 3 days on the 3rd filter, I was able to procure an extra cord of fire wood, (which I need to stay warm for 2 more months).
4th day, it would not shift into 4th gear. The pressure was correct at 90 psi in drive/O-drive, 75 psi in Neutral, and 210 in low 2 /Low 1.

It still has pressure now, however when it is supposed to shift at 45-51 mph, it does not. The cable was perfect for 3 days, so it's not the cable.
Drove it back home from a 2 mile trip at 35mph and now it's parked.
It still moves, so it can be relocated when it warms up for removal. No sense in damaging anything further.

The exact cause of failure and how the frozen governor effected the entire drive line for 12 months and 2100 miles, (Dec 2020 - Dec 2022) has yet to be explained to me... It requires disassembly and rebuild.

Starting a new thread for advice for my new to me replacement truck, until the cash can be acquired to ship this across country to the builder... $700 I cannot afford to send right now...

Hope the pictures of the gauge set up assists someone else...
The good news, is the pump appears to be working OK.
The converter, I'm not so sure about...
Lot of metal on the magnet...

Will update as the rebuild moves forward.
 
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Ricko1966

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M8ne,Napa brand,too cheap,too easy,for me to even think about building one.
 

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RanchWelder

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Well, the NAPA is $123.00 shipped...

Had a 300psi gauge and figured others might also...
...and the brake line is rated to 1200PSI over the cheap rubber hose they give you with crimped brass ends, (which would not be as good as a stainless line for permanent install.

The parts I listed comes up to $74.10, delivered.

If you have a gauge, you'd have saved $48.90 and have a superior hose assembly, in my opinion. It's been snowing for 3 days here and the barn is still full of tractor.
Have not pulled the transmission or started on a possible replacement vehicle.

For now, I have no vehicle.
 

Ricko1966

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Well, the NAPA is $123.00 shipped...

Had a 300psi gauge and figured others might also...
...and the brake line is rated to 1200PSI over the cheap rubber hose they give you with crimped brass ends, (which would not be as good as a stainless line for permanent install.

The parts I listed comes up to $74.10, delivered.

If you have a gauge, you'd have saved $48.90 and have a superior hose assembly, in my opinion. It's been snowing for 3 days here and the barn is still full of tractor.
Have not pulled the transmission or started on a possible replacement vehicle.

For now, I have no vehicle.
Well done,sir. I guess yours is a money saver,I guess I'm just lazy.
 

RanchWelder

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Nah, your cool.
 

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