This is strong evidence that the cam shaft seal needs replacing. 🙂
This is a fairly straight forward repair. That said, care is needed to avoid scratching or damaging the camshaft when removing the old seal.
This is the parts list. I also replaced the points and condenser.
|11 14 1 261 193||Cam shaft seal||1|
|65 61 2 300 654||Cam Housing Gasket||1|
|12 11 1 243 555||Points||1|
|12 11 1 351 564||Condenser||1|
Remove Points and Timing Plate
I removed the existing points assembly, and will replace it with a new set of points. Their is a single machine screw holding the points shown in the top right of this photo at the 1:00 position right next to the points.
This exposes the timing plate which is attached with two longer machine screws at the 12:00 and 6:00 position. I remove the 6:00 screw first so I can detach the points wire from the metal tab securing it. Then I disconnect the points wire from the condenser and removed the wire out of the long rubber sleeve. Then I removed the 12:00 screw leaving the timing plate free for removal.
Remove Camshaft Seal
I twisted the timing plate to get it loose to expose the camshaft seal, shown here as a black seal around the camshaft. The seal on the /5 is not very large. The black bits at the bottom of the casting came from my attempt to remove the seal with a pick tool, which failed as it only shredded the rubber seal.
Next, I used a heat gun to head the metal housing around the seal and then very carefully inserted my adjustable seal puller next to the camshaft to carefully pull the seal out. I don’t want to pry against the camshaft and I don’t want to scratch the outside of the boss the seal mounts into. It popped out.
Shaft Seal Puller
I also found a YouTube video on how it is used and that sold me on this type of puller. I ordered it for the next time I have seals to pull. I think this design reduces the risk of gouging or scratching the boss and the camshaft.
Install New Camshaft Seal
I used brake cleaner to clean the camshaft and the boss the seal goes in to be sure everything is nice and clean and there are no sharp edges on the boss. A 5/8 inch spark plug socket fits the new seal nicely and it’s what I used as a drift to install it.
I put the seal in the hole and squared it up, then put the 5/8 socket over the camshaft and gently drove it home with a plastic mallet.
Install New Points and Condenser
I replaced the old condenser with the new one. Then I snaked the new points wire up the long rubber tube and attached it to one of the spades on the condenser. Their is a second wire from the back of the timing cover that goes on the other spade.
I find adjusting the timing plate with a screwdriver on the two longer machine screws requires a large blade and invariably the slots get chewed up. So I visited my local ACE Hardware and got two Allan head cap screws, M4 x 0.7 x 10 to replace them.
After attaching the cleaned up timing plate with the new Allan head cap screws, I installed the points with the original shorter machine screw. Then I inserted the timing came and attached it with the 10 mm nut being careful to not over tighten the nut. Now, I can adjust the timing plate with the timing cam and centrifugal advance weights on the cam shaft with a small Allan wrench. It will be a lot easier to adjust the timing and I won’t have rounded slots on the machine screws to contend with.