That may not be sludge, there is a wick in there. I like that bushing with the hole. My bushing seems like hardened steel ?
So many variations over the years..

You might also check out Green Auto Parts or Sales. They have a huge Inventory of Obsolete Parts. If it doesn't show on their inquiry site U might contact them direct and see what they have.

  

Dennis Carpenter and Mustangs Etc. are supposed to have the bushings, according to Rearcounter.com Thing is, this part and other 'strib parts don't show up at their website when inputting the part #s. So what is the deal with Rearcounter anyway? How and why do they know inventory that the site in question does not? Strange.

good reminder, I had forgotten about Green.

Yeah I saw the wick, I meant the cavity between the housing and bushing. Well I ordered one of the distributor shafts and a gear. In for a penny, in for a pound I guess.

Ok wanted to back up a bit here, an earlier part number for the "upper" bushing (Y Block distributors have only one) is B7A-12120-A (replaced or superceded by B8HQ-12120-A); a search on the former also finds several on hand at a few different vendors, many of the same ones.

The dimensions are listed as: (.469" ID, .688" OD, 1.75" LONG); these numbers jibe exactly with the bushing removed from one of the cores yesterday. Whether it matters which number is ordered, or they are different as a practical matter I dunno. Looks to me though, they are just fine, plus, any supply house should have an equivalent bushing.

The distributor gear - FAE-12390-A these are all over the place in terms of dimensions with respect to the thrust surface thickness and even where the pilot holes are drilled. This is why the manual cautions (I think) they can't be swapped around. So long as the gear is not excessively worn if the dimensions are adhered to by proper placement on the shaft they "should" be able to be re-used, seems to me.

"...an earlier part number for the "upper" bushing (Y Block distributors have only one) is B7A-12120-A (replaced or superseded by B8HQ-12120-A)"

B8QH 12120-A

Where did you come across B7A 12120-A being replaced by B8QH 12120-A?

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Ted, is that for the steel bushing or the older oilite with the hole?

Not sure, the bushing I ordered from tbirdhq, appears from the pic to be bronze colored, and (I think) has an oil hole. They don't use actual Ford #s on their site, and the places that have either part in stock don't have pics. I thought oilite doesn't need the oil hole though.

The parts will be here soon enough so I'm trying to get a better handle on the dimensions. The bushing gets driven home till it bottoms on the step, located in the base of the housing. This sets the proper bushing height, it still sits proud of the distributor bowl, but the distributor shaft itself should not run on this surface in operation.

So lacking the special tools Ford used, to set the proper endplay and locate the collar on the new shaft, could install (temporarily) a .022" shim or washer on the shaft, on top of the bushing basically. Then, run the collar all the way up flush with the distributor base. Using the collar holes as a guide, drill a 1/8" hole in the new shaft. Remove shim washer, reinstall everything and then pin collar. So now have the 0.022" end play spec'd in the book.

(1st question is why is the spec 0.022" to 0.032"? Wear is the where? Er, where is the wear normally?? It looks like the extra 0.010" spec'd must be the accepted limits past the normal endplay? Remember the shaft doesn't ride on the bushing, so I don't get it. The endplay will never tighten up! If I'm thinking correctly, then in any case 0.022" end play is golden, measured between the collar and housing base. Or do they figure some people will screw up, and up to 0.032" is OK?)

So that leaves locating the gear on the shaft properly. Once again Ford had special tools. Looking at different gear manufacturers like MSD, Crane, whoever, there are different instructions when installing their gears. The Ford manual says "remove endplay" before locating gear. So does everybody else - but, "somebody" is wrong! I think. Because, some folks say pull down, others say push up! I can probably figure it out by looking at the dimensions of the core I have, but.

So what do they mean exactly by that "remove end play" - extending the distributor shaft down as far as it will go by 0.022" OR, pushing up on the distributor shaft so the collar is tight against the housing?

It seems to me the shaft should be pushed up, with the collar against the housing when taking this measurement, and then the gear installed/located 4.991" to 4.996" as measured from mounting flange to bottom of gear. Notice this is different technique than when actually checking for the proper dimensions.

edit: distributor shaft should be extended as far out as it will go. I think. LOL


Keeping in mind the desired result is that the base of the gear should ride directly on the machined thrust surface in the block with a good wear pattern on the gears, while at the same time the distributor shaft weight should not ride on the bushing, ideally keeping the end play to a minimum etc etc.