| Also known as | T3953 |
| Diagram | Fig. 12 — INNER AND OUTER CHAINCASE · ref 15 |
| Subsystem | primary |
| Listed in parts books | 1969–1970 |
Outer primary chaincase
Outer primary chaincase cover for the primary drive, catalog number 57-3953 (also listed as T3953).
This is the outer primary chaincase, part number 57-3953, listed in the parts books under the older T3953 form as well. It's the outer cover of the primary chaincase assembly, the housing that closes over the primary chain, clutch, and engine sprocket on the left side of the motor. Paired with the inner chaincase, it keeps the primary drive enclosed and running in its oil bath.
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The catalog shows this part appearing in records spanning 1969 to 1970, listed under the INNER AND OUTER CHAINCASE figure. If you're matching this up to a specific machine, check your existing chaincase and inner cover for shape and mounting points before ordering, since the parts book doesn't spell out which models beyond that year span it was cataloged for.
If you're replacing the whole primary cover setup, you'll want to look at the inner chaincase and the gasket or sealing arrangement between the two halves as well, since they're catalogued together.
We've never carried this one. Tell us what you're after and we'll go looking — you'll get a price and photos before you commit to anything.
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