Distributor disassembly, bearings, and O-rings
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Thanks to Jeff Gibson and Charlie Mullendore of Antietam Classic Cycle for sending me the following information and photos on how to disassemble the distributor to replace the bearings and O-rings. In Charlie's own words and photos:
Last night was the first time I've ever needed to disassemble a Tontidistributor. Lots of oil inside and all over the outside, so something had to be done about it.
I figured it used a felt seal similar to the Loop distributor, but it's completely different. The shaft runs on two 6001-RS1 sealed ball bearings and there are two O-rings on the shaft, one O-ring at each bearing to seal the shaft to the bearing. The O-rings were hardened andsackedon this one, so no wonder it leaked. Just eye-balling it, the O-rings looked to be the same size as those for the cylinder studs. Sure enough, they seem to fit perfectly.
Thanks to Jack Huisinga for sending me this additional information about the :
Replaced in distributor. This Distributor is a Marelli S311B. The shaft is supported by two double shielded bearings. The shaft has two slots cut into it so that the seal between the inner bearing bore and the shaft. The that fits is a 9.25 mm × 1.78 mm
And in Jeff's own words:
I'm wondering if you can help/advise regarding the above: I'm now reassembling an S3 distributor, that was completely dismantled and boxed away (embarrassingly) several years ago.
Generally, I'm ok with where everything goes, except for one O-ring - the two circular section ones are obvious, sitting on the shaft within the bearings as they do, but I've also got a SQUARE section O-ring, of much the same dimensions as the circular ones, but with no obvious location.
I've searched quite extensively, but can find no reference to it, nor has anyone I've asked - sadly there are no parts diagrams to help - obviously Marelli didn't intend them to be dismantled!
Is this something you've come across at all?
I attempted to help, but Jeff figured it out entirely on his own. In his words and photos:
Just a note to properly close this out.
I have identified where this O-ring goes!
Checking each part during reassembly, I spotted witness marks on the thin rectangular insulatingwasherthat sits on the plate on which the bob-weights pivot. The O-ring sits on the distributor shaft (ID being slightly smaller than the shaft at this point), and is presumably designed to hold the insulatingwashertight down to the plate.
I attach a couple of pics in case anyone else asks!