Vaccum Cans
Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
I was afraid of that Gordon. Hopefully I can fix it with some bushings.
I wish I would have known this while I had it all apart changing the intake out. I set the endplay on the distributor to around .007" and was tickled with the outcome. I wanted to get it to .005. Not enough correct shims. I could have done something about the weights too.
I am sure I could buy replacement weights. I am guessing the combination of worn weights and plate are adding up to give me the 9 degrees instead of 18 degrees.
I wish I would have known this while I had it all apart changing the intake out. I set the endplay on the distributor to around .007" and was tickled with the outcome. I wanted to get it to .005. Not enough correct shims. I could have done something about the weights too.
I am sure I could buy replacement weights. I am guessing the combination of worn weights and plate are adding up to give me the 9 degrees instead of 18 degrees.
Last edited by Eddie 70; Jan 2, 2006 at 10:07 AM.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
It is not the weights that give you the amount of advance it is the plate and the pin that goes into the plate. It is like a slot and the slot gets elongated and allows the pin to travel further therefore giving you more advance. the weights and springs just tailer how fast it comes in. Once you see it apart you will see exactly how it works. A picture is worth a thousand words as they say.
To do it right you have to pull the dist and pull the shaft out. Not really a big deal. I pull mine it seems like about 4 times a year. It is much easier to work on it out of the car.
To do it right you have to pull the dist and pull the shaft out. Not really a big deal. I pull mine it seems like about 4 times a year. It is much easier to work on it out of the car.
Last edited by Gordonm; Jan 2, 2006 at 10:13 AM.
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
Eddie, You need to attend (or arrange) a Larsfest! 
He had my distributor out, and lubed and bushing replaced and vac can replaced and timed in about 10 minutes flat! (OK, maybe it was 30 minutes, but it was just a blur). Would have been the best $200 I ever spent on my car and my education, but it worked out to about $50 a piece! 
He had my distributor out, and lubed and bushing replaced and vac can replaced and timed in about 10 minutes flat! (OK, maybe it was 30 minutes, but it was just a blur). Would have been the best $200 I ever spent on my car and my education, but it worked out to about $50 a piece!
Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
If I were a tooth off would that cause this problem. I am sure I am a tooth off right now also.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Originally Posted by Eddie 70
If I were a tooth off would that cause this problem. I am sure I am a tooth off right now also.
Tech Contributor
Joined: Aug 1999
Posts: 14,375
Likes: 6,375
From: At my Bar drinking and wrenching in Lafayette Colorado
Eddie -
If you're runing 9 degrees initial timing with 36 total, you are missing the advance stop bushing in your distrubutor. This causes the curve to go long. Pick up Mr Gasket part number 927 or 928. Either one of these kits will have a little brass stop bushing in them. You will need to pull your distrubutor, disassemble it, and press the brass bushing onto your stop pin. This will shorten your curve and get you more initial timing while maintaining the 36 total. DO NOT use the weights in the Mr Gasket kit as they will really screw up your advance curve.
If you're runing 9 degrees initial timing with 36 total, you are missing the advance stop bushing in your distrubutor. This causes the curve to go long. Pick up Mr Gasket part number 927 or 928. Either one of these kits will have a little brass stop bushing in them. You will need to pull your distrubutor, disassemble it, and press the brass bushing onto your stop pin. This will shorten your curve and get you more initial timing while maintaining the 36 total. DO NOT use the weights in the Mr Gasket kit as they will really screw up your advance curve.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Originally Posted by lars
Eddie -
If you're runing 9 degrees initial timing with 36 total, you are missing the advance stop bushing in your distrubutor. This causes the curve to go long. Pick up Mr Gasket part number 927 or 928. Either one of these kits will have a little brass stop bushing in them. You will need to pull your distrubutor, disassemble it, and press the brass bushing onto your stop pin. This will shorten your curve and get you more initial timing while maintaining the 36 total. DO NOT use the weights in the Mr Gasket kit as they will really screw up your advance curve.
If you're runing 9 degrees initial timing with 36 total, you are missing the advance stop bushing in your distrubutor. This causes the curve to go long. Pick up Mr Gasket part number 927 or 928. Either one of these kits will have a little brass stop bushing in them. You will need to pull your distrubutor, disassemble it, and press the brass bushing onto your stop pin. This will shorten your curve and get you more initial timing while maintaining the 36 total. DO NOT use the weights in the Mr Gasket kit as they will really screw up your advance curve.
Just came in from the garage and you are correct as usual Lars. I pulled the distributor and the hole is not worn nor is the pin for the advance plate. The rubber bushing is worn into where it contacts the hole. I pulled the rubber bushing out. My distributor is tach drive any precautions I need to take before pulling it apart to install the bushing you are talking about? I have had it apart before and thought nothing of the tach drive and it still works. I may have just got lucky once. Twice, I may not be so lucky.
I do have an HEI kit for the springs but it has some plastic bushings in it. Are these what I need to limit the advance plate travel?
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Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
The bushing in my kit are all .250 diameter on the outside. I know there is no chance of getting one of those Mr. Gasket Kits locally. The brass bushings are an interference fit correct. I have one of the bushings from my kit on the stud(???) and it was a nice tight fit also. I think it will do the job. Tell me if I am ok to go like this.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Summit carries the kit and it is only $7.25. Handling is $9.50. That is the BS.
I guess I can look around and find me about $100 worth of stuff I would like to have and then place the order.
I did put the plastic busing on the distributor and it was a tight fit. I am going to use it till I get the kit in. Not like I am going to be driving it everyday.
I guess I can look around and find me about $100 worth of stuff I would like to have and then place the order.
I did put the plastic busing on the distributor and it was a tight fit. I am going to use it till I get the kit in. Not like I am going to be driving it everyday.
Burning Brakes
Joined: Jun 2002
Posts: 837
Likes: 3
From: Texas
Eddie...that brass bushing in the Mr Gasket kit measures .265" OD X .186" ID if it's any help. There's at least two auto parts stores in this dinky town that stocks that 927-928 kit. It's easy to find.
I think after reading this post I may pull mine again and install that bushing.......wish I had thought about it when shimming the endplay. I'm showing a low initial timing (about the same as yours) but am having no problems with the way it runs anywhere in the rpm range. I'm just wondering if I might be able to improve it a bit more.
Good luck with it Eddie
Rip
I think after reading this post I may pull mine again and install that bushing.......wish I had thought about it when shimming the endplay. I'm showing a low initial timing (about the same as yours) but am having no problems with the way it runs anywhere in the rpm range. I'm just wondering if I might be able to improve it a bit more.
Good luck with it Eddie
Rip
Tech Contributor
Joined: Aug 1999
Posts: 14,375
Likes: 6,375
From: At my Bar drinking and wrenching in Lafayette Colorado
Eddie -
If you have a snug-fitting 1/4" diameter bushing you can slip on the pin, just use it. Anything to increase the stop pin diameter will help limit your curve and get you a bit more initial advance.
No trick to pulling things apart. With the distributor out, pull the tach drive crossgear out first. With that out, knock the roll pin out of the distributor gear and slide the whole mainshaft out of the housing. Once out, you can slide the cam plate off the shaft, and then access the pin for installation of the bushing. Be sure it fits very snug, or it can fall off and short your points out. I like to give the bushing a little hit with a hammer to make it out-of-round for a tight fit, but then I like any excuse to tune using a hammer.
Lube things up prior to re-assembly. Install the gear with the dimple pointing the same direction as the firing tab on the rotor. Good luck!
Lars
If you have a snug-fitting 1/4" diameter bushing you can slip on the pin, just use it. Anything to increase the stop pin diameter will help limit your curve and get you a bit more initial advance.
No trick to pulling things apart. With the distributor out, pull the tach drive crossgear out first. With that out, knock the roll pin out of the distributor gear and slide the whole mainshaft out of the housing. Once out, you can slide the cam plate off the shaft, and then access the pin for installation of the bushing. Be sure it fits very snug, or it can fall off and short your points out. I like to give the bushing a little hit with a hammer to make it out-of-round for a tight fit, but then I like any excuse to tune using a hammer.
Lube things up prior to re-assembly. Install the gear with the dimple pointing the same direction as the firing tab on the rotor. Good luck!
Lars
Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Lube things up prior to re-assembly. Install the gear with the dimple pointing the same direction as the firing tab on the rotor. Good luck!
Lars
Lars
Thanks for all of the help guys. I believe I am back in business. Just have to wait on the kit to arrive.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
As it turns out, I did have my distributor gear installed incorrectly. 50/50 chance and I lost. I also looked up the kit Lars recommended and it is back ordered at Summit. So I called one of my buddies and he was going to have one shipped to his store, guess what he cannot get it either. Oh well, my car is not going to be running anywhere too far anyway.
I just wanted to add that before this post I did not really understand the whole timing scheme. I have learned a lot from this post and enjoyed the heck out of it. There is really not all that much too it once someone points you in the right direction. Thanks for all of the help guys. That is what this place is about.
I just wanted to add that before this post I did not really understand the whole timing scheme. I have learned a lot from this post and enjoyed the heck out of it. There is really not all that much too it once someone points you in the right direction. Thanks for all of the help guys. That is what this place is about.
Last edited by Eddie 70; Jan 3, 2006 at 08:46 PM.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Just wanted to add a few photos that I took while doing this job.
This is the top of the distributor with the springs removed and one weight remived. My distributor was a greasy mess. It has now been cleaned up somewhat using MEK.
This is the slot that the advance plate moves about in. You can see there is no wear on the ends of the slot.
This is the pin that rides in the advance plate. There is supposed to be a bushing on the end of this pin that sets the amount of advance you have at idle. Mine had a rubber bushing when I took the distributor apart and was worn through. It was allowing the distributor to fall back to 9 degrees at idle when it should have been quite a bit higher.
This is the top of the distributor with the springs removed and one weight remived. My distributor was a greasy mess. It has now been cleaned up somewhat using MEK.
This is the slot that the advance plate moves about in. You can see there is no wear on the ends of the slot.
This is the pin that rides in the advance plate. There is supposed to be a bushing on the end of this pin that sets the amount of advance you have at idle. Mine had a rubber bushing when I took the distributor apart and was worn through. It was allowing the distributor to fall back to 9 degrees at idle when it should have been quite a bit higher.
