Overhauling a '57 Hydramatic

[Roger Zimmermann]

Nothing fancy to report: today was cleaning day. That brown crust from the old oil is difficult to remove; I did as good as I can. The side levers were assembled; I'm now waiting for the ordered parts.
The pictures are showing the parts which are ready to assemble and the side levers.

[Roger Zimmermann]

As the parts from Dave Edwards arrived recently, I could begin yesterday with the assembly. But first, I cleaned a bunch of parts and I did a mysterious discovery: a small hole drilled into the breather tube, pictures 41 & 42. As this transmission was never overhauled, I can see that the holes were done before the paint. Why? Mystery!
When the steel clutch discs are good, I'm using them again. On those transmissions, the plates for the rear clutch are not flat but have a wave pattern. To have a consistent gear change, the plates must be aligned like shown on the picture 43. I used to see "overhauled" transmissions with plated installed incorrectly. Since some years, when the steel plates for the rear clutch are ordered, they are perfectly flat, one reason more to use the old ones if they are good.
The picture 44 is showing the competed clutch pack. On top of that the rear clutch piston assembly is coming. Once this assembly is in place, the drum for the neutral clutch can be installed as well as the clutch discs. For this clutch pack, the metal ones are flat; the picture 45 is showing how the whole is looking. Of course, each disc is oiled with transmission fluid before installation.
It's now the turn for the center bearing support. To be able to assemble the whole unit into the transmission, a special tool is needed to compress the neutral clutch and avoid that the various thrust washers are getting out of place. Now the whole unit (picture 46) is ready to be installed into the case. Boy, it's heavy!

[Roger Zimmermann]

The clutches and shafts are now placed horizontally (picture 47) and can be placed into the case. The shop manual is well explaining that the center bearing support must be aligned correctly compared to the slot from the neutral clutch case.
You can see on the picture 48 that the unit is in place. Will I have to take it out again due to a problem as I did for almost all transmissions I overhauled?
There is a lubrication hole on the output shaft, picture 49. This hole must be aligned with the one from the reverse carrier assembly, picture 50. The other parts are installed without problem; now, the rear of the transmission is ready, picture 51. Now, it's time to check the function of the various clutch's pistons with compressed air, picture 52.

[Roger Zimmermann]

As the test with compressed air was OK, I can install the front oil pump. This is always a gamble: if not entered straight, it gets cocked in the bore and/or the thrust washer at the back gets dislodged. This time, it went in place the first time! (pic. 53)
Once the bolts from the oil pump torqued correctly, the front unit coupling can be installed. Sometimes it will not go in place easily, sometimes it does it without problem. I assume that the steel seal rings are the cause.
Now, it's time to check the front unit end play with the special tool J-6282 and the associated spacer #1, picture 54. In this case, the original selective spacer is flush at the tool, I can use it again.
Once this test done, I can assemble the valve body, taking care that all the attaching screws are tight, picture 55.
As the owner had fun to begin the disassembly with me, I'm keeping the front parts to be assembled with him when he will come in about 10 days. Due to a bad planning from me, I forgot to let check the cooler assembly. It should be ready early next week.

[savemy67]

Hello Roger,

Nice work.  Of the controlled coupling transmissions you have rebuilt, did this unit give you the least trouble?

When it is fully assembled, I imagine it will weigh more than 100 kilograms.  Will the owner help you lift it into the owner's car for transport, or do you have a shop crane?

I noticed that some of the tools needed for working on the transmission were fabricated by you, and some tools are the original Kent-Moore tools.  In the case of the end-play tool, do you think that can be fabricated easily?

Christopher Winter

[Roger Zimmermann]

Hi Christopher
Thanks for your comments. Yes, this unit could be assembled without trouble, compared to the 3 others I did earlier this year. As I had for 2 years no transmission to overhaul, I did forget some specificities like the assembly of the rear pump with the ball bearing which is sometimes a pain to assemble on the output shaft. Apparently, the lessons learned from the 3 others were useful this time!
As I have a scales in the "garage", I will use it to determine the weight (never thought to do that before); I assume it's about 100 kg. The owner will help to some extend; from the table to the trunk of his car, I will use a shop crane. I unloaded the transmission that way.

Yes, I have some home made tools; I fabricated first the end-play tool with brass and came later across the original one. I sold my brass tool to somebody in the Netherlands. If needed, I can give you the dimensions and do some from near. You will need a spacer #1; Dave Edwards has them.

[savemy67]

Hello Roger,

That would be great if you can send me the dimensions of the brass end play tool you fabricated.  Others may be interested, so you can post here or send me a PM.  Thanks.

I will contact Dave as needed.

Christopher Winter

[Roger Zimmermann]

I will do that the next few days!

[Roger Zimmermann]

Yesterday was the final assembly, together with the owner. to my dismay, I forgot to take pictures except when all was ready! Anyway, the remaining work is well described in the shop manual. And Christopher, I forgot also the weigh the transmission! I remember at that once the transmission was placed into the trunk of y car and neither the owner not me were motivated to take it out again, sorry.

[Roger Zimmermann]

Christopher ask me for the dimensions of the tool J-6282. Here they are, but metric as I will never understand how to convert in fractions.

That tool is done in two parts.

The first one has an outside diameter of 56.4mm; the inner diameter is 42.8mm. The length is 50.8mm

The second one is not so simple: the outside diameter is 42.7mm, the inner diameter at the ribs is 31.9mm on a distance of about 15 mm. After that, the diameter is 33.1 mm; the length is 51.9mm.
The ribs are square and are 1.4 x 1.4 mm.

The inner tube cannot be separated from the outside tube with a short elastic pin. To allow some movement, the inner tube has an hole which is about 15mm in diameter.
When I did mine, the tubes could be separated and I don't remember if I did only 1 or more ribs. I had anyway the same result with the home made and the Kent-Moore tool.

The spacer #1 has an outside diameter of 48.2mm, the inner one is 43.2mm.It is 1.78mm thick.