How to replace advance weight pins in distributor?

[camrycurt]

Hey guys,

I've got a question about replacing the advance weight pins in a stock GM 6 cylinder HEI distributor. The PO upgraded my 1970 C10 with a 230 inline 6 to HEI with a 6 cylinder GM HEI (with the separate coil).

Last weekend I finally got around to pulling the cap and rotor off the distributor to have a look around and found that the bushings on the advance weight pins were long gone and the weights had been flailing around in there for goodness knows how long. As a result, the pins are worn about halfway through and the holes in the weights have been worn into ovals.

I was already in the process of ordering an advance curve kit so I'll have new weights, bushings, etc., but I'm wondering about replacing the worn pins. Rockauto sells the replacment pins, but it wasn't clearly evident to me how they're fastened in - it looks like they just slide in.

Has anyone replaced the weight pins in a stock GM HEI distributor and can tell me how the pins are held in? Is it just friction? Do I just grab the old pins and pull? Do I need to completely disassemble the distributor to get them out?

Thanks so much for any help.

[beautimus]

i don't have any info to offer on this, but i'll be watching this thread myself.

any specs on your ride like gearing, mpg etc.? any way ttt for ya.
Tony

[screamin_c10]

Some were pressed in with a knurl (much like a wheel stud), others were pressed in and staked, you will have to determine which method was used on your particular distributor...

"The counterweight mounting pins are then removed by grinding the staking material away and pressing or punching the pins out of the rotor plate....."

so, yes, you will need to disassemble the distributor so that you can remove the shaft in order to access the backside of the rotor plate. If the pins are simply pressed in then drive them out with a punch and press the new ones in, if they were staked or brazed you will need to braze the replacement pins in...

this link has alot of good info:

http://www.chevelles.com/techref/ftecref5.html

[camrycurt]

screamin,

Thanks so much for the info and quick reply. I knew it wouldn't be as simple as grabbing and pulling. I'm not real keen on taking the distributor apart right now so I think I'll start by just cleaning up the worn pins - once they're smooth with no burs and I get the correct bushings back on I'd guess they'll be OK.

Tony, I just picked up the truck a couple of months ago and am in the process of going front to back to clean up all of the easy stuff - one of the next things I need to do is change out the fluid in the rear differential so I'll have a chance then to look around and check gearing, etc. So I don't really have any info to provide right now. I can tell you that I like the 230 I6, but mating that with an SM465 means that I'm about the slowest thing on the road and MPG is miserable. But that's fine with me because I'm in no hurry.

Of course, having a distributor with a jacked up mechanical advance doesn't help either, plus I don't even think the vacuum advance can is working. I've got a new one to put in but want to get the mech advance squared away first before I start tuning and everything.

Actually, I have to say that the truck runs amazingly well for everything that is wrong with it. With all of the vacuum leaks and non-functioning parts, it shouldn't be running at all. As it is, with screwed up timing and no advance it idles smooth at about 300 RPM and only occasionally backfires through the carb. I'm hoping that once I get the timing tuned and everything fixed up the power will pick up and she'll run like new.

[screamin_c10]

Originally Posted by camrycurt

screamin,

Thanks so much for the info and quick reply. I knew it wouldn't be as simple as grabbing and pulling. I'm not real keen on taking the distributor apart right now so I think I'll start by just cleaning up the worn pins - once they're smooth with no burs and I get the correct bushings back on I'd guess they'll be OK.

Curt, it is actually a pretty painless process rebuilding an HEI... If you leave the void in the pin then all the new weight has to ride against is the plastic bushing and it will eat through it in no time.... I'd go with Geezer's suggestion and grab a Skip White HEI IF he sells them for the six. If not grab a junk yard unit and use it as practice/parts so you are more confident about tearing yours apart.

Bill

[camrycurt]

Originally Posted by screamin_c10

If you leave the void in the pin then all the new weight has to ride against is the plastic bushing and it will eat through it in no time

Bill

Bill,

I hadn't thought of that but of course you're correct - thanks for the heads up.

If I go the rebuild route on the mechanical advance on the distributor, does anyone have any tips on what else should be done once I get everything apart? Just clean and lube everything and make sure it's all moving as it should?

Thanks again everyone for all the help.

[geezer#99]

Buy a new HEI from skip white. Only 65 bucks on ebay. Then you don't need to chase all the little parts you'll need.

[screamin_c10]

Originally Posted by geezer#99

Buy a new HEI from skip white. Only 65 bucks on ebay. Then you don't need to chase all the little parts you'll need.

Hey Geezer, does Skip carry an HEI for the six? I know he has them for all the popular V8s FORD and Dodge inluded....

[geezer#99]

I have bought 2 from skip white on ebay.

[Sport/Truck]

Originally Posted by geezer#99

I have bought 2 from skip white on ebay.

I like that motor!

[stich626]

fill the groove with pumping soider, then emery cloth..
no need to tear it apart..
good luck

[camrycurt]

Originally Posted by stich626

fill the groove with pumping soider, then emery cloth..
no need to tear it apart..
good luck

Hey, that's a good idea too. So regular plumbing solder is strong enough to resist the wear from the weights?

[stich626]

Originally Posted by camrycurt

Hey, that's a good idea too. So regular plumbing solder is strong enough to resist the wear from the weights?

the pin only holds the bushing the bushing takes the weights,,
and no if you let it go through the bushing it will do the same to the pins,,
lack of p/m is why they are past the bushings in the first place..

[Jacfourteen]

If you tear down the dizzy, you should get a shim kit to shim up the up/down movement of the shaft/rotor. Excessive end play will cause fluctuation in timing. I have about 3/16" up/down play in mine right now and it causes timing problems above 4000 RPM. Here is an article I read the other night that has some good info.

http://www.rustynutscarclub.com/HEI.htm

[VetteVet]

Here's a great website.
http://www.rustpuppy.org/ignition2/Ignition%202b.htm

[camrycurt]

This is all great information and a big help. Thanks to everyone for the responses!

[Roadmarks]

I think the L6 HEI from Skip White is fairly new, but if you can't find it listed, call and ask!
I have seen 'em on ebay.

@camrycurt . . . Is the Mighty Midget still there? Their parking lot looked like a rod show every Saturday night!

[camrycurt]

Originally Posted by Roadmarks

@camrycurt . . . Is the Mighty Midget still there? Their parking lot looked like a rod show every Saturday night!

Roadmarks, the Mighty Midget is still here, but it's now a German Biergarten place: http://doener-usa.com/locations.html And I'm not sure about the car show anymore but will have to check it out!