What happens in a transmission rebuild - Part 11

[Mac VP]

LINK TO ORIGINAL POST:
https://www.fordbarn.com/forum/showthread.php?t=278347

PART 11 will deal with the installation of the rear housing (or extension housing as also known). We have already installed the rear housing bushing, the rear oil seal, and the lockout shaft oil seal. The 7656 internal snap ring has also been installed (hooked ends up toward the access opening in the housing).

Now we will place the lockout shaft into the side of the housing....from the inside. The operating knuckle will hang downward and the shaft will be pushed through from inside out. The bore in the case for the shaft should be clean and well lubricated. Twist the shaft slightly as you push it through all the way as far as it will go. This process leaves the shaft sticking out about 1/2" beyond its normal installed location. It must remain out like this during the installation of the extension housing to the rest of the transmission.

Compress the 7685 lockout rail spring slightly and place it in the tail housing between the two openings designed to hold it. I use a tapered drift punch to help align the spring with those openings. The two photos below show the install with the drift punch and its installed position in the housing. This drilled passage is plugged with a small 3/8" plug at the rearmost end of the opening. It will be helpful to remove that plug for the housing installation. Save the plug to put back in place later.

The extension housing is now ready to be dropped onto the rest of the transmission (which is sitting vertically on the bench). The first of the housing drop pictures shows me guiding the casting down over the mainshaft, planetary gear, and freewheel cam assembly. Make sure that the 7686 lockout shaft remains pulled out as far as it will go during this process. It's easy to bump it with your body as you wrestle the housing down in place. You can look down through the little lockout rail opening (3/8" hole now facing upward) to help guide the housing so that the lockout rail enters this passage. You will also be watching the transmission mainshaft pass through the rear bushing and rear oil seal. If you did all this correctly, the complete extension housing will now be resting on its own but about 1/2 to 1" away from being fully seated.

You can observe the 7656 snap ring through the access opening in the housing. Until you spread this snap ring, the housing cannot move further down into place. Use the lockring pliers to spread the snap ring. Sometimes you are lucky and the housing will drop enough that the snap ring has moved past the edge of the ball bearing, at which point you remove the pliers. Sometimes you have to rap down on the housing with a soft dead blow hammer (at any obvious locations near the mounting flange). This should move the entire housing nearly all the way down. Occasionally, there can be interference with painted surfaces or gasket material that prevent the housing from dropping totally into place. If this happens you can draw it down by temporarily putting 3 or 4 of the housing bolts into their respective locations and gently tightening them up a bit at a time (evenly drawing them down) to move the housing all the way. If the housing will not draw down with modest tension on the bolts, stop and raise the housing to try again.

When you are satisfied that the extension housing is correctly seated, remove the bolts that you may have temporarily installed. Make sure that they are clean. Coat the threads with your favorite thread locking compound (we use Permatex blue gel thread locker). Add fresh lock washers to each bolt and install them. The torque ratings for these bolts were never published in any of the Ford service manuals. However, using SAE standard torque ratings for the 7/16-14 SAE Grade 5 bolts, it is recommended for a maximum torque of 50 lbs dry and 35 lbs lubricated. I guess you could consider the thread locking compound to be a lubricant and adjust according to your preference.