Auxiliary Transmission Images

Started by jdemaris, January 31, 2004, 11:32:53 PM

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jdemaris

John de Marrais here.  Guess I'm the moderator, although I don't know what a moderator does.  In the mean time, I going to post some images to this thread individually until there is something more formal set up.
  This image is two Ford Model A 3 speed transmissions, side by side, rear view.  Left one is modified and has original Cletrac Spicer u-joing spider installed. Trans. on right is original and unmodified.

jdemaris

#1
Diagram of clutch actuating arm that will have the same travel and pedal pressure as original Cletrac HG or OC3.

jdemaris

#2
Modified Cletrac clutch housing with steel transmission mouting plate welded to it.  A separate diagram with specs. will be posted.  The plate I welded to the bell housing was 3/8" steel plate, but it tends to warp slightly when welded.  So, once welded and cooled, the assembly was finished milled - in order to make sure the plate was smooth and also to insure that its surface was perfectly parallel to the engine mounting end of the bell housing.

jdemaris

#3
View from top with original clutch housing and driveshaft out to show modified clutch pedal mouting and linkage.

jdemaris

#4
New Ford Model A clutch disk to be used in place of original Cletrac disks.  Both are 9" diameter.  Ford on left, Cletrac on right along with original Cletrac pressure plate.  Note: new Ford disk is installed backwards, i.e. side marked "flywheel side" must face AWAY from flywheel.  
  Also, the HGs and OC3 came with two different versions of pressure plates.  Image only shows one of them.
  New Ford Model A disk, with dampening springs is available from many places that sell Ford repro. parts.  Cost $40-$60.  I don't advise buying one from NAPA.  It won't be new, but will be an old relined disk and won't have the dampening springs.

jdemaris

#5
Front view of modified clutch housing.  7/8" diameter shaft made from cold-rolled steel with Ford Model A throwout-bearing fork. Steel bushings with 7/8" i.d. were welded into the housing for the new clutch release shaft to ride in.  Bushings are available for a few bucks from many farm supply stores - they are sold as 3 point hitch adapter bushings.  Notice that this Cletrac housing has the access hole on top; some don't.  It's a nice feature and makes assembly easier.  When final installation is done, there is one bolt mounting hole that gets blocked by the new clutch cross shaft (bolts that attach to engine).  I drilled and tapped one new one to compensate.

jdemaris

#6
Original image not mine and can't remember where I got it.  I digitally installed the Ford Model A speed to show how it all fits.

jdemaris

#7
View of aux. Model A trans. installed with modified fuel tank mount.  I left the tank off for photographic purposes.  Shift lever was heated and bent to clear tank, and top was threaded to accept original Cletrac shift knob.

jdemaris

#8
View of modified Ford Model A transmission and fabricated driveshaft.  This driveshaft uses the original Cletrac (Spicer) u-joints and comes apart sideways.  Works very nice.  Original Trasco aux. driveshaft setup was not removable without damage - or pulling engine.

jdemaris

#9
Closeup of farbricated driveshaft using original Cletrac/Spicer u-joints and yokes.  Comes apart sideways.  I added grease fittings.

jdemaris

#10
Two Ford Model A three speed transmissions (for car, not truck).  Left one is modified for use in Cletrac, right one is original.  The optional aux. that Trasco used modified the input shaft on a Model A trans to use the Cletrac disk.  Why, I don't know.  I don't modify the input shaft and simply use a Model A disk.  Modifications to the trans. are easy and low-tech with no machine shop work necessary.  I do recommend removing the original ball bearings and installing modern sealed bearings.  I have the specs. and part numbers.

jdemaris

#11
Modified Ford Model A trans. with fabricated mounting plate attached to the front of it. The plate I bolted to the Model A transmission is 1/2" thick.  I think using the plate is necessary for a number or reasons. It provides a place to bolt the fuel tank mount to.  Also, the four bolts that are used in mounting the Model A transmission, when used originally in the Ford car, come through the inside the bellhousing.  So, the transmission cannot be removed by itself since these mounting bolts cannot be accessed unless the engine is out.  I wanted the transmission to be easily removable, so with the adapter plate, it is bolted to the trans with the bolts pointing towards the trans, and then,  four bolts pointing the other direction mount it to the modified bell housing.  This way, you can access and/or remove four bolts at any time and easily remove the trans. (with plate still attached to it).
  The throwout bearing and carrier in the photo is what I used and is NOT Ford.  I have specs. and more info.

jdemaris

#12
I don't have a degree in mechanical drawing, so don't complain to me.  What do you want for free?

jdemaris

#13
Original Cletrac HG/OC3 mount on left, modified for aux. setup on right.  Modifed version bolts to fabricated adapter plate on the Model A trans.

jdemaris

#14
Original Cletrac HG/OC3 mount on left, modified for aux. setup on right.  Modifed version bolts to fabricated adapter plate on the Model A trans.