C2 distributor advance weight posts

[John G.]

The advance weight support posts in my '64 distributor are worn through about 1/3 of their original diameter. I have new replacement posts. What is the best way to remove the old posts from the advance weight base plate? .. Once removed what is the best way to install the new posts so they stay permanently in place? .. TIA ..

John

[Joe L.]

Re: C2 distributor advance weight posts

John-----

Where did you get the replacement posts? I din't know that these things were available or, for that matter, replaceable. They were never available from GM as a seperate part as far as I can tell. I assume that you are talking about the posts on the distributor cam assembly. These are the only ones that wear due to the pivotting of the distributor weights upon them. Lack of lubrication causes wear.

Anyway, while I've certainly never done it, the only way that I could imagine that these posts could be replaced, if they can be replaced, at all, is to press them out from the BOTTOM. The posts have a flange at the base and could not be pressed out from the top. However, some how or other, I think that these posts are somehow induction-welded, brazed, or otherwise "fused" to the cam assembly. I believe that I have seen repairs, though, that involve the SLEEVING of the posts. If I recall correctly, a thin stainless steel sleeve is pressed over the posts. Then, the holes in the weights are bored slightly oversize to accomodate the increase in the OD due to the sleeves.

Beyond all that, whether they can be replaced, or not, if the posts show this much wear, I would not be surprised if the distributor cam is worn, too. Usually, the wear on the distributor cam is much more of a "life limiting factor" than the wear on the posts. Check the cam carefully. Wear is usually very discernable since the contact set rubbing block only contacts the center portion of the cam. Therefore, it's easy to compare the contact and non-contact areas.

Bad news and good news: the distributor cam assemblies are long-since GM discontinued and, as far as I know, are not available from any aftermarket or restoration source. The good news is that the cam assembly is the same as that used in other, non-Corvette distributors. So, you may be able to salvage a decent one from another distributor if you need one.

[Joe L.]

Addendum

By the way, if the distributor cam is worn, but you can replace the posts (or, obtain another cam assembly with good posts but a worn cam), then there is another solution. If you convert the distributor to an electronic ignition with the installation of a Breakerless (or, similar) conversion kit, then the distributor cam becomes irrelevent.

[Clem Z.]

distributor rebuild parts

http://www.kendrick-auto.com/ignition.htm there are nylon bushing kit that can be installed into the weights after the holes in them are drill larger that can be used to fix the worn post poblem. the GM weights are hardened so you must heat the area around the hole red hot and let it cool slowly to anneal this are so it can be drilled over size

[John G.]

Re: C2 distributor advance weight posts

Joe ..
Yes, these are the posts that the advance weights pivot on. I got the replacement posts from another member over on the Corvetteforum website. I hadn't known if these posts were available, or not, up to that time.

The bottoms of the installed posts on the cam plate assembly do seem to have a tiny smattering of some kind of 'material' spread about on them. Some kind of induction welding or braze as you suggested? .. It would seem easy enough to just drill out the old posts and go from there. The big concern is getting the drill hole dead center, of course. I had thought to hard solder the new posts in place to the cam plate. Brazing does seem to be the better alternative, though.

I did check the cam itself and it appears to be ok. There is some discernable wear but it doesn't appear to be excessive. Seems those breakerless ignition systems are a popular way to go. I had wanted to keep the points system usable, if possible.

I see that advance weight posts are available from the site Clem posted.
Thanks for the replies ..

John

[Clem Z.]

with the replacement bushings in the weights

you do not need to replace the pins which could be a big problem getting them out and back in. check your auto parts for the bushing kit as i have repaired HEI distributors with these kits.

[Duke W.]

Re: C2 distributor advance weight posts

BWD offers a pivot bushing for HEI distributors (DG1) and an installation tool (DG2). Also the nylon pivot bushings for HEI centrifugal weights, DG13, which are worn out if your HEI has over 50K miles, and they have not been replaced.

You can order the all these parts from Pep Boys, but I believe the weight pivot pins are HEI only and I'm not sure if they fit on single point and TI distributors. For sure the pivot bushings are HEI only. Single point/TI distributors do not have weight pivot bushings as OE. Be sure what you have is the same diameter, length, and spring retention grove as what's installed.

The only small dist parts I've been able to find for the single point is the felt washer, DG12 (also used on HEI and should be oil wetted) and the single point/TI limit bushing, DG3.

I've not been able to find the plastic seal for the grease well (The felt washer rests on this seal) or new breaker plates.

Duke

[Clem Z.]

the HEI weight pin repair bushing is for .157 dia

pin,what is the point distributor weight pins diameter? also any good machine shop could make you repair bushings of the correct size so you do not have to try and R/R the orignal pins

[John G.]

Re: C2 distributor advance weight posts

Duke ..

LIC has the plastic seal for the grease well. I recently ordered a new plastic seal, felt washer, and other parts from LIC. The LIC catalog also shows the cam and plate assembly listed in their distributor parts schematic. But it's listed as "N/A" ..

HEI bushings? .. Too bad they won't work on a points distributor. That kind of fix almost seems 'too easy'! .. The new advance weight posts I have closely resemble the originals.

John

[John G.]

Re: the HEI weight pin repair bushing is for .157

Bushings would sure make life much easier than replacing those posts. I test fitted one of the new posts into a spare advance weight to check clearance fit. The post fit snug inside the advance weight hole and moved freely. Using a digital caliper the post diameter measured out at .184 ..