It has been mentioned before in the changes that occurred over the years to the Mark 5/V that there was one change in 1961 around the time going from the Gilmer Drive to the Poly V Drive that
Units with a “C” at the end of their Serial number during this time require a special Quill.
The picture below is the Vent/serial number plate from one of those Mark 5’s. The suffix “C” appears to be hand engraved on the plate after the serial number.
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How was this Quill “special” that differed from the Quill for the Gilmer or Poly V Drives. Was there any other differences? The answer comes from Forum Member John Dalton and his recent addition of a Mark 5 Goldie serial number 369904C made in March of 1961. John has shared information and pictures of those differences. The Headstock parts appear to be original and the V belt even has the Yuba name on it.
The Quill in his “C” suffix Goldie has a shorter outer sleeve. The picture below shows a Quill Assembly on the left from an earlier Mark 5 and the special Quill Assembly on the right.
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That is not the most notable difference though. The Drive Sleeve Assembly has the biggest difference. The center sleeve itself does not have splines but appears to possibly be using the nylon splined cap from the Mark 2 Drive Sleeve Assembly. This is similar in function to the Drive & Ring which is current part number 514083 used on all Mark 5/V’s since the change to the Poly V Drive in 1961 but with six splines. The cap for the Mark 2 and the one used in these Mark 5’s are attached to the Drive Sleeve with two screws. Below is a picture of an early non-clutched Gilmer Drive Sleeve Assembly on the left and the Drive Sleeve Assembly from S/N 369904C on the right.
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John didn’t have one to compare it to so below is a picture of a Clutched Gilmer Drive Sleeve Assembly. The plastic cap seen on this one does not have splines and is a simple friction fit.
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Below is the cap itself from S/N 369904C
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Below is the cap from my Mark 2
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We can only guess why these suffix “C” machines existed. Was it to use up the early 6 splined Quills and Gilmer clutched gears when the center sleeve from the Gilmer Drive Assemblies had all been used up. Using the cap from the Mark 2 Drive Sleeve Assembly appears to have made that possible. So why was it necessary to shorten the outer sleeve of the “special” Quill?
