Ok, I am completely rebuilding my distributor. My question is: When I completely clean my dist. housing. How do I go about repacking/oiling the oir reservoir, for the top bushing? Thanks in advance...

 

ah-ha! I new this one would stump you. I've been thinking cutting foam rubber to size. Then putting some heavier oil in it. I know that is what is done on electric motor bushings.
If anyone knows better, jump on in...

 

I would just pack some grease in there down to the tabs (about1")
This how GM ships it new:

 

Well, I can see I am missing that cover that goes over the reservoir. So, under the tab, there is a light grease? Ummmmm Many Thanks

 

The screen goes above what you see (no cover) then pick-up/magnet etc. When you remove the shaft and pick-up this is what you should see, the bottom of the relucter(attached to the shaft) serves to cover over the top of where you see the grease. Tabs I am refering to are about an inch down from where you see the grease in the picture and hold the bushing in the casting.

 

Ok, I got ya, I didn't look closely enough at that picture. Do you have an idea what type of grease they are using. I do believe it has to seep into the top bushing.
Since I want to do this rebuild right. I am going to replace the bushings. Call me inexperienced on this situation, but how do I remove the bushings? I've done alot of mechanic work, but never have done this.
I am appreciating your help Mick. Thanks alot...

 

No problem, I'm glad it helps but unfortunately I do not know what they used for grease. I can only guess that a quality bearing(axle) grease should be alright.
Yes, the method of lubricating will be from seepage and heat, weird method but works. I haven't removed the bushings either because I could not just locate just bushings when I re-built mine.

However what I would have done is to use a long drift (steel or brass rod) smaller in diameter than the dist. shaft. Put casting in the vise put the drift in tap out bushing from the inside going out. Take the drift and by going around the edge of the bushing from the back side (inside the casting) slowly, as to not elongate the allum. casting. Turn dist. casting over and repeat the process. Pressing them would be easy enough with a big vise w/wood jaws. Bottom bushing will be flush to the casting after pressing it in, the upper one has stops inside the casting but I would still measure the distance that the bearing sits above the casting before pressing it in all the way.
Additionally just like press fitting any part (u-joint caps on some cars, roll pins etc.), making sure that the bushing is set-up straight is important, that allum. is cast and not very heavy duty. Hope this helps

 

Very Helpful Mick, I appreciate your time. Many Thanks, Tom

 

Cover = "Retainer, pole piece & plate". Part number 830446, for 1984 - 1985.

Screen = "Screen, W/Support". Part number 830639, for 1986 - 1989+?

RACE ON!!!

 

Thanks Jim, That is very helpful. I've found I can't buy dist. bushing anywhere. They want to sell me the shaft along with it. By the time it is said, and done. I could buy a rebuild, and get on with life...

 

If you have more time than money, you can probably get bushings many places. Maybe even Lowes or Home Depot. Certainly McMaster- Carr or Grainger's would have something you could fit to the job. The GM parts book doesn't show the bushings. It does show a "housing assembly" which includes:

Retainer, pole piece and plate.
Pole piece, w/ plate.
Screw, w/lk ws,Modile attaching.
Module, distributor.
Shield, module.
Capacitor, w/bracket & screw.
Terminal Block.
Seal, housing.

The housing assembly part number is 1988614.

Remember, too, that the bushings have nothing to do with end play.

RACE ON!!!

 

Thanks Jim, I beleive you know me pretty well. I do have more time than money. Yes, I know the bushings have nothing to do with the end play, unless you don't position them correctly in the dist. housing.

I am hatching a scheme. Ok, say you disassemble your distributor competely, removing both bushings, maybe just the bottom one. Ok, you have on the lower outside portion of the dist. housing two guides that fit into the block to position the dist. gear onto the cam gear. Ok. now the void in between those two guides is where oil flows to one side of the lifters. I've been doing some measuring. Now in this void you drill a hole near the top guide at or near 45*. Ok, you just miss the top of the bushing. Now oil will spray through the hole onto the shaft. I better mention the the hole would need to be drilled into one of the spokes that hold the lower dist. bushing. This would put the hole about a 16th inch away from the shaft. Now as the oil sprays on the shaft, it will lube the bottom dist. bushing, and there will be enough oil that doesn't make it into the bushing, as a matter of fact the better portion of the said oil. Now this will run down the shaft, and on the outside of the bushing, along with what get sprayed on the inner dist. housing as well. This oil will run down through those spokes, and oil your dist. gear, as well as the cam gear. The trick is not to drill to big a hole.

Thought I would run that by you, and see what you think. If you can understand my little word diagram above...

 

Bump

 

Interesting question adn I have your answer, since my company manufactures those bearings your talking about!

What the bearings are comprised of is a two part system we refer to as a bi-metal bushing. The OD of the part is made up of iron powdered metal while the ID is made up of a bronze P.M. material. This two part system was developed by us here and has gone into every distributer I know made today. We make about 250000 a week here!

PM material is porous in nature and has about 15% porosity, this makes application where bearings are used VERY adventageous, since we can oil impregnate the bearing and even where direct oiling is not available, the bearings self-lubricate during use.....

And there-in lies your answer you were looking for. You could vacuum impregnate them in your favorite oil - but I honestly think if you just submerged them in oil, they will suck the oil into their pores and you will be good to run them for MANY MANY moons. If they are new, then they are already impregnated here and you can just run them.

Hope this helps! Good question!

 

While I understand the materials and process is diferent, are they then classified as an "oilite" ?

 

Hey Thanks ski_dwn_it, Yes, I have vacuumed many bushings. They have all been the smaller type. I've even vacuumed oil into sealed ball bearings. Mostly on computer fans, and my rc helicopter. Being an electronics tech. I have run into many situations that needed this type of fix.

I realize the porous nature of the dist. bushings top, and bottom. They are already lubed for you for some length of time. I was thinking however, that my idea would serve two purposes. The bushing being constantly oiled is a fringe benefit. I have examined many distributors from different GM vehicals, and I have noted the wear on drive gears. Seems the small block chevys have a chronic problem of wearing out the gear, which caused fluctuations in timing. Therefore, my idea would lube that gear quite readily. Which I would hope would help the dist. gears life span. This is a little different way of doing it. Crane Cams have an interesting way to go about dist. gear oiling. They tell you to file or machine a .030" slot in the bottom dist. guide. This inturn supplys the gear with oil. Very interesting, like I said before, "the hole would have to be rather small". I do have a set of circiut board drill bits. They get so small you can barely see them.
Thanks Again...