tachometer oil seal

How difficult is the tachometer oil seal top change out? About to order a bunch of stuff and wanted to get this little fire put out.

Very easy.

The tach drive assembly is held into the head with a single bolt. While you don't have to remove it from the head, it's usually easier to do it this way.

Get the 10mm o-ring that goes around the outside of the drive as they often will leak as well as the tach seal.

When removing the old seal, be sure to get out all its cremains, which may be baked, encrusted and carbonized (maybe even petrified) in its position.

The seal is a small circular rubber ring affair with a tiny coiled spring around it.

A dental pick or similar tool is handy to scratch out the remains.

Click > Z1E Hook and Pick Set

A good light and magnifying glass is also helpful.

Good Fortune!

When new tach seal and 0-ring are properly installed, there will no oil leakage whatever from inside the valve cover through the tach drive, even without connecting the tach cable.
Could ride cross-country without a tach cable, and without any oil leakage from the tach drive.

People are wrong when thinking the tach cable must be tightly fitted to the tach drive in order to prevent oil seepage from the tach drive area. This may "catch" the oil seepage and collect it inside the tach cable, but does not "repair" the leaking tach drive (which isn't supposed to be leaking in the first place).

Good Fortune!

The worst case situation is when seals fail and oil is pumped up the tach cable, possible dripping out or getting into the instrument itself.