pp000830

Recently I sent my distributor in for a new belt and other servicing as needed. When I removed it with the belt intact at 100K miles the gear turned effortlessly signaling that the bearings were probably in good shape.

Each time I replace the rotors and caps I put a small amount of motor oil on the components under the shield below the rotor. Upon removing the rotor I noticed that there was a small puddle of oil along the lower of the two rotor housings. This is probably excess oil from earlier lubrications.

This is my theory; If the mechanism is oiled with each rotor/cap change does it contribute to keeping the bearings lubricated and so they do not dry out, overheat and become damaged?

Conversely, if the distributor is not lubricated when the cap and rotor are replaced do the bearings eventually run dry and wear out?

Other's thoughts and experiences?

evilfij

No idea about Porsche distributors, but I do that on my other cars so that the rotor is easier to remove next go around.

CalvinC4S

I believe the bearings are sealed and the thing to watch with the 993 dual distributer is oxidization from ozone.

Tlaloc75

I don't think Ozone is much of an issue with the 993, that was solved after the 964 exhibited this failure mode.

NC TRACKRAT

I believe some of the early 993's didn't get the Ozone tube fix and a recall was issued to rectify same. There may still be some out there that didn't get it.

Tlaloc75

You may be thinking about the 964. The fix was added in 1993.

I did notice once that my hose had fallen out, down at the bottom of distributor where its hard to see. So that's a good thing for everyone to check. Once it falls out, it aint doing much good any more.

pp000830

I understand the ozone issue with the belt but seeing that my belt is 20 years and 100k miles old I think they have that issue licked. My car does have the vent tube.

The bearing issue is one where a bearing begins to fail and the added torque demands on the belt, as a result, snap it.
Could it be after 20 years the seals on the bearings are not so well sealed and the incremental additional lubrication from above provides some gravity feed to them? Looking at the application and the very low forces involved a little lubrication would go a long way!
Other's thoughts?
Andy

Tlaloc75

I haven't been into mine yet, but I like the idea and can't see how it would hurt. I'm going to oil mine, that's for sure.

Did you just use normal motor oil? If so I'll go add some brad penn this weekend

CalvinC4S

The vent tube greatly extended the life of the belt over the earlier non-vented distributer. However, I still believe ozone to be the leading cause of distributer failure over bearing lubrication.

It's not uncommon to see a 964 or 993 these days with the vent tube missing or not installed properly.

Another concern is the ozone resistance of the replacement belts being used.

Only time will tell.

Edit to ad: Not saying it's not bearings, makes sense to keep an eye on them.

Tlaloc75

That's right... the belt composition also changed to make them more resistant. Forgot about that.

pp000830

Regular motor oil.

JDHertz11

You've been here long enough to know not to bring up what "regular" motor oil is. Here we go again... ****...

Tlaloc75

Lol. I will only use Brad Penn 20w50 on my distributor. Anything else will break down and destroy the engine.

drb930

Think about you are a brand new set of bearings built in circa 94-98 from Porsche's bearing distributor with fresh grease inside.
Now you have spent 20+ years in a hot distributor with ozone with imperfect seals, maybe moisture too.
Would you dry up?
We used to lube up the weights & shaft in all distributors during tune-ups years ago, really made a difference.
I think putting some type of oil that will get past the factory bearing seals would help... ACf-50 is what I like...

Thanks,
Dave

95_993

Salt and salt air in coastal areas will likely have a corrosive effect over time on all metal surfaces..