A question regarding the 2.8 (and possibly 2.5 as well) distributors.

In my case, I have a newer star-toothed-wheel replacement, but I believe the discussion should be applicable to all.

Anyway, when I pulled my distributor for cleaning/maintenance, the shaft was hard to turn. So I took off the gear, polished the shaft, oiled her up, and re-assembled that distributor. After that polishing/oiling job, the shaft turned freely.

Some time later (a few years, perhaps), the shaft was again hard to turn. Of course, there's no pressurized oil supply to the bushing up top near the pickup coil...

So how should this upper bushing remain lubricated? Is oiling at every tune-up required? Is there supposed to be an oillite bushing that "releases lube for life"? If that's the case, mine is dead.

My dizzy won't have a pick-up coil, so it should be fairly simple to apply a few drops of oil to the upper distributor bushing every 3000 miles or so, if it comes down to that.

I have never heard of 'oiling the distributor'. There is plenty of oil at the base that should get pushed up the shaft. Maybe the type of oil you are using is the issue?

Is it possible that there's enough splash and oil vapor within the crankcase that the engineers deem it enough to sufficiently lubricate the bushings? I believe the bushings are Oilite brass. I don't think I've ever seen any distributor that had any direct lubrication.

There is plenty of oil around the distributor.

How many times have we all seen oil leaks at the base of the distributor, or added a SBC gasket to augment the O-ring seal on the distributor housing.

Try priming an engine with a drill (without using a modified distributor to drive the pump) and get back to me with the results.....

How about those older style crusty rusty parts under the dist cap that seem to work anyway. I always thought maybe theyd be better cleaned up. But...does it matter? I also wondered if it would be asking for problems. It seems like they were never painted so they get rusty.

2.5, the corrosion is caused by the ozone concentration in the cap....

quote Originally posted by olejoedad: 2.5, the corrosion is caused by the ozone concentration in the cap....

I guess my thought is, would painting or oiling or apllying some kind of corrosion inhibitor , or removing rust crust be advised or not for any reason?

You could I suppose, but the dizzys work well even when Rusty...

quote Originally posted by 2.5: I guess my thought is, would painting or oiling or apllying some kind of corrosion inhibitor , or removing rust crust be advised or not for any reason?

Yes... To all of the above.

My SBC distributors would also oil starve at the top of the drive shaft. My cure was to use a grease rather than oil on it, and to touch it up every tune up.
My dual point dist. used needle bearings which I also greased.

The metal corrosion inside the cap should be addressed with clear coat laquer or other paint to prevent bare metal being exposed to the ozone air inside the cap.
I would not cover the bare metal with oil or other lube to protect it, as the mist of the lube will contaminate the cap and rotor and cause carbon tracks and loss of spark. But if you have points and mechanical advance weights, a drop of oil on the pivots is OK.
The metal corrosion can also lead to arcing and carbon tracks, so cleaning it up as best as you can or replacing the corroded parts helps.

A good reason to switch to coil packs with no distributor cap and rotor use,just a crank sensor to trigger the packs, or an on crank trigger system. Then you can eliminate a lot of problems of a distributor.

Crash

Sintered brass and others w/ oil "built into" them can have two problems...
OE oil can eventually "dry out" and bearing gets no oil.
People try to fix them using whatever oil/grease available. May clean or not before adding lube... Works for days to months but often will bind up worse then before. If cleaned, the cleaner will still be in the pours the bearing and attack the new lube. Can take days or longer to get rid of many cleaner. No cleaning? the OE oil can still make problem for new lube.

If those things don't happen, New lube often won't work for long because people uses wrong lube.
Example: WD40, CRC 5-56 and Many others are not oil to lube moving parts. Many have VOC etc that evaporate most to all of them leaving a sticky mess. Some in seconds to hours or even day/weeks later.
Normal "White grease" and some others are same for this. Wrong oil/grease for thrust and rotational bearings for part that reaches 500-2000 RPM and more. (I forget Gearing ratio etc right now and don't care to search.) DIST shaft may look easy but in the engine and running that gear puts big thrust and rotational loads on the bottom end but gets engine oil to cool and lube. Top end of shaft have less loads but more then most think and often doesn't get allot of lube.
Many times White grease doesn't work for low speed parts either. May Work for HL and other motors because not on all the time. Wiper motors can self destruct if white grease is used because can't handle Motor speed and worm gear pressure for a start. Output shaft is low speed but high torque and pressure to drive wiper transmission.

Then add whatever oil/grease you use can cause shaft seal problems. Wrong lube hardening or softening a seal can cause oil leaks etc.

Add Dist gear is often Oil Pump drive in many engines. Meaning dist problems can be cause OP problems. Even pumping heavy oil or install high volume/pressure pump can put more load on the dist gear and shaft.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

[This message has been edited by theogre (edited 06-28-2018).]

quote Originally posted by crashyoung: My SBC distributors would also oil starve at the top of the drive shaft. My cure was to use a grease rather than oil on it, and to touch it up every tune up. My dual point dist. used needle bearings which I also greased. Crash

Which particular grease do you use, and where was it applied?
What are your thoughts on this:
http://www.chevelles.com/me...ch/jun_tech/681.html

[This message has been edited by 2.5 (edited 06-28-2018).]

quote Originally posted by pmbrunelle: My dizzy won't have a pick-up coil...

Can you expand on that?

quote Originally posted by 2.5: Which particular grease do you use, and where was it applied? What are your thoughts on this: http://www.chevelles.com/me...ch/jun_tech/681.html

Dist lube in that thread likely a Lubriplate (Maybe 130), Standard Lubricam, etc, product made for lubing points where it rubs the shaft lobes. Is often a thick grease that won't run/move. Many point sets came w/ grease for this.

quote Originally posted by olejoedad: There is plenty of oil around the distributor.

Oil at the bottom does not imply oil at the top...

quote Originally posted by fierofool: Is it possible that there's enough splash and oil vapor within the crankcase that the engineers deem it enough to sufficiently lubricate the bushings?

Well my Fiero's engine did make it past its warranty period, so yes?

quote Originally posted by fierofool: I believe the bushings are Oilite brass. I don't think I've ever seen any distributor that had any direct lubrication.

Now I seem to remember sticking a magnet to the upper bushing, and it does seem ferromagnetic. So it wouldn't be brass. But maybe there are oil-impregnated ferrous bushings out there?

I do think the upper bushing must be ferromagnetic for the distributor to work.

Normally, when the 6-pointed star lines up with the 6-pointed fixed star, the permanent magnet induces magnetic lines as follows:

The magnetic field lines go in closed loops:
1. Up the distributor shaft
2. Radially outwards to the points of the rotating toothed star
3. Into the points of the fixed star
4. Down into the base of the fixed star
5. Radially inwards towards the bushing
6. From the outside of the bushing, to the inside of the bushing
7. From the bushing into the distributor shaft (back to step no. 1)

EDIT: I missed the magnet in that circuit, but its location depends on the distributor variant (new or old style).

Only when the points are aligned may the magnetic circuit support many field lines.
When the points are not facing each other, there are fewer field lines.
The pickup coil generates a voltage depending on the change in the number of field lines going through the distributor shaft.

If the bushing had low magnetic permeability (meaning a material that does not allow magnetic field lines to form easily in it, such as brass), then I think the pickup coil wouldn't work.

quote Originally posted by crashyoung: My SBC distributors would also oil starve at the top of the drive shaft. My cure was to use a grease rather than oil on it, and to touch it up every tune up.

I thought that grease, being thick, would cause friction and heat.

But I guess it's better than having the oil run down and operate dry!

Since I don't have a pickup coil to worry about, I may be able to retrofit an oilite bushing or a needle bearing... hmmm... but probably I'll leave it alone since I want to get the beast running in a matter of months, not years.

quote Originally posted by 2.5: Which particular grease do you use, and where was it applied?

Crash, I want to know too!

quote Originally posted by css9450: Can you expand on that?

I'm tossing the OE computer and HEI in favour of a MegaSquirt 3 sequential injection system, with a homebrew cam sensor (in the dizzy, actually).

[This message has been edited by pmbrunelle (edited 06-28-2018).]