Oil leaking from the Tachometer cable

[ejws]

Hi all,


Wintertime has started, so it is time to chase for oil leaks...
In my BT7, I noticed drips of oil on the connection of the tachometer cable to the distributor and tachometer housing (AEC685).



For sure, the fibre washer (Nr. 29; 2K4970) was not leaking, so I suspect the oil seal (No.30; 3H964) in the tach pinion bush (No.28; AEC701).





After removing tach pinion bush, I had two questions:
1.) How do I easily remove the oil seal retaining ring (No.31; 1G340)?
2.) How should a new seal be mounted? Flat side to the outside world or to the tachometer pinion?





Note that the retaining ring has been pressed fully into the tach pinion bush and that the aluminium plate in the tacho drive cable was screwed tightly against the bush.
Next time I mount these together, I will use an additional fibre washer to overcome irregularities in edges of the two pieces.


Note 2: The picture of the oil seal originates from AHSpares.

Best regards,
Erik

 

[Healey Nut]

You will need to remove the whole tach drive assembly from the distributor and push the seal out from the back side once you have removed the pinion gear . Install the new seal the same way the old one came out .

 

[ejws]

Hi 'Healey Nut',


Maybe I don't get it, but how can you push out a seal via a shaft that has the same diameter as the inner diameter of the seal?
Note that the pinion gear axis (27) is sealed by this seal (30).

At the other end, the seal is locked up by the oil seal retaining ring. There is no ribbon in which I can peek a hook.

So, the only possibility I saw, was using a hook and try to rip the seal apart and get it out is parts. Than I might use the hook (or maybe two hooks) to pull the ring out.
But I was hoping for smarter and less destructive options...

Up till now, I received variants on following recommendation:
+ Make a rod that just fits. Glue it with loctite 638 on the ring. Wait a day. (Heat up the brass housing a bit.) Pull it out.
Finally heat up the rod to make the glue fluid again and remove the ring.


Maybe I should go ahead with that one.

 

[Madflyer]

What about buying a new cable seems like a lot of work over an easy swap of cables. Just asking .Madflyer

 

[John Turney]

What about buying a new cable seems like a lot of work over an easy swap of cables. Just asking .Madflyer

Because the seal is not part of the cable, it's part of the tach drive.

 

[Healey Nut]

Hi 'Healey Nut',


Maybe I don't get it, but how can you push out a seal via a shaft that has the same diameter as the inner diameter of the seal?
Note that the pinion gear axis (27) is sealed by this seal (30).

At the other end, the seal is locked up by the oil seal retaining ring. There is no ribbon in which I can peek a hook.

So, the only possibility I saw, was using a hook and try to rip the seal apart and get it out is parts. Than I might use the hook (or maybe two hooks) to pull the ring out.
But I was hoping for smarter and less destructive options...

Up till now, I received variants on following recommendation:
+ Make a rod that just fits. Glue it with loctite 638 on the ring. Wait a day. (Heat up the brass housing a bit.) Pull it out.
Finally heat up the rod to make the glue fluid again and remove the ring.


Maybe I should go ahead with that one.

Ok let’s try this again . With the whole tach drive removed from the distributor . Slide out the pinion gear . Now you have a hole to slide a skinny rod into from the gear end of the tach drive to push out the retainer ring and seal . You are going to destroy the seal and maybe even damage the retainer ring .
Rebuild in reverse order without damaging new parts , reinstall drive and enjoy .