Distributor Tester
#1
Distributor Tester
Who here remembers the old Sun and a few other brand names that I can't recall at the moment, distributor testers? I have been battling a flood of crappy distributors lately and sure wish I had a tester so that I can definitely tell what the problem is. I have looked for testers on-line and the only things I have found are the old 60's vintage testers. Distributors were used up until approximately 2000 and there are millions of them still on the roads. Why can I not find anything newer than 60's vintage testers? Even when I find an old Sun, they want $3000 for it. In my opinion that is absurd. If it fails and needs parts you are SOL. Tough to swallow that kind of money for something that old and unsupported. Thoughts?
#3
Kenneth, was it a spinning distributor tester or more of an engine analyzer? Do you remember what brand it was? I've got an old engine analyzer, but I need to spin the distributor so I can see what the mechanical advance + vacuum advance are doing. Also see how stable the point plate is.
#4
Remember them, used the Sun scope a ton. Just about every tuneup was scoped. Also used it to test coils and alternators, power balance, wire resistance etc.
We had valve grinding equipment, and a brake lathe in the shop.
We had valve grinding equipment, and a brake lathe in the shop.
#6
Same...service station I worked in H.S. had a big SUN machine. Can't even find a service station today...let alone anyone who knows how to turn brakes or know what it means.
#7
#8
#9
Yes, people want crazy money for those old Sun distributor machines! I had one in the 1970s which I used quite often doing $15.00 or $20.00 distributor tune ups for the local crowd. I also miss the Mallory points, best and longest lasting.
#12
Man! you lucky devil you! That looks pristine. I appreciate the offer to spin mine, but I need my own so I can try different curves and find what is best. I have 3 old cars and it would be nice to have if it won't break the bank. Well, my bank anyway.
#13
This guy says you can build your own for <$100
http://www.ourdigitalmags.com/public...articleBrowser
http://www.ourdigitalmags.com/public...articleBrowser
#14
#15
This guy says you can build your own for <$100
http://www.ourdigitalmags.com/public...articleBrowser
http://www.ourdigitalmags.com/public...articleBrowser
#16
#18
#19
Not true. You still have mechanical and vacuum advance in electronic ignitions. The electronics replaced the points only. With fully computerized ignitions, which started coming into being at around the 2000's, then you no longer had a distributor, but as long as there is a distributor there is mechanical and vacuum advance. Well, if it has vacuum advance. Could be purely mechanical.
Last edited by 69oldsguy; November 30th, 2023 at 07:04 PM.
#20
Not true. You still have mechanical and vacuum advance in electronic ignitions. The electronics replaced the points only. With fully computerized ignitions, which started coming into being at around the 2000's, then you no longer had a distributor, but as long as there is a distributor there is mechanical and vacuum advance. Well, if it has vacuum advance. Could be purely mechanical.
#21
This guy says you can build your own for <$100
http://www.ourdigitalmags.com/public...articleBrowser
This is the most comprehensive article that I have seen on constructing a "shade tree" home shop distributor machine. It covers the basics required to spin and test a distributor off the vehicle and he explains it all at a level that I believe most people with a basic understanding of vehicle tune up can understand. Nice that he included pictures, charts, etc. in the original article.
http://www.ourdigitalmags.com/public...articleBrowser
This is the most comprehensive article that I have seen on constructing a "shade tree" home shop distributor machine. It covers the basics required to spin and test a distributor off the vehicle and he explains it all at a level that I believe most people with a basic understanding of vehicle tune up can understand. Nice that he included pictures, charts, etc. in the original article.
#22
click on original link
when page loads, there are 4 icons on the upper left
the third one down looks like an open book - click on that
It brings you to the actual article with pictures
#24
True enough, but I'm not a big fan of free revving my engine to 4000rpm. I don't even free rev to 3000rpm. I currently have no idea about the mechanical advance curve on the distributors I have. They may not be full in until way up there. I've seen it before. I have an advance timing light, but I don't trust that it is very accurate. At the end of the day, I may not have many choices though. Thanks everyone.
#25
Here is a screen shot of his actual machine.
#26
Hi,
Here's the pdf link
https://www.corvetteforum.com/forums...-randolph-.pdf
Also if you keep a eye out as I got 2 used Distributor machines a few years ago for 400 bucks, one was a 50's era Sun which worked and a Allen that needed work and flipped it for 200.
There is a company that sell restored machines and parts to restore one you have or find, all depends upon what you feel comfortable fixing.
Regards,
Jim
Here's the pdf link
https://www.corvetteforum.com/forums...-randolph-.pdf
Also if you keep a eye out as I got 2 used Distributor machines a few years ago for 400 bucks, one was a 50's era Sun which worked and a Allen that needed work and flipped it for 200.
There is a company that sell restored machines and parts to restore one you have or find, all depends upon what you feel comfortable fixing.
Regards,
Jim
#28
Hi,
Here's the pdf link
https://www.corvetteforum.com/forums...-randolph-.pdf
Also if you keep a eye out as I got 2 used Distributor machines a few years ago for 400 bucks, one was a 50's era Sun which worked and a Allen that needed work and flipped it for 200.
There is a company that sell restored machines and parts to restore one you have or find, all depends upon what you feel comfortable fixing.
Regards,
Jim
Here's the pdf link
https://www.corvetteforum.com/forums...-randolph-.pdf
Also if you keep a eye out as I got 2 used Distributor machines a few years ago for 400 bucks, one was a 50's era Sun which worked and a Allen that needed work and flipped it for 200.
There is a company that sell restored machines and parts to restore one you have or find, all depends upon what you feel comfortable fixing.
Regards,
Jim
#29
#31
Not true. You still have mechanical and vacuum advance in electronic ignitions. The electronics replaced the points only. With fully computerized ignitions, which started coming into being at around the 2000's, then you no longer had a distributor, but as long as there is a distributor there is mechanical and vacuum advance. Well, if it has vacuum advance. Could be purely mechanical.
True enough, but I'm not a big fan of free revving my engine to 4000rpm. I don't even free rev to 3000rpm. I currently have no idea about the mechanical advance curve on the distributors I have. They may not be full in until way up there. I've seen it before. I have an advance timing light, but I don't trust that it is very accurate. At the end of the day, I may not have many choices though. Thanks everyone.
The distributor testers pop up from time to time for <$500 but you gotta be checking FB Marketplace, local swap meets, etc. Paid $300 for ours with the cabinet. It works well with points distributors, but I haven't upgraded it to work with electronic ignition conversions yet. You can sink a ton of money into them.
#32
You're off by 20 years - the computer controlled distributors started in the early 1980's. The GM cars all had 7 pin HEI modules with a computer to control timing. No weights/springs/vacuum cans. You had to jumper pins on the ALDL connector to set your timing with the car running.
Last edited by joe_padavano; December 5th, 2023 at 06:33 AM.
#33
In fact, first used on the 1977 Toronado 403 with the MIcro-processed Sensing And Regulation (MISAR) crank-trigger ignition system. Later seen on the Olds 260 with the C4 system in 1980 in California, which was the precursor to the CCC system (apparently to avoid confusion with the upcoming C4 Corvettes) on 307s in the 1981 model year.
#38
You're off by 20 years - the computer controlled distributors started in the early 1980's. The GM cars all had 7 pin HEI modules with a computer to control timing. No weights/springs/vacuum cans. You had to jumper pins on the ALDL connector to set your timing with the car running.
#39
Which ones? Trucks maybe, which were subject to less stringent emissions requirements than were cars. I can tell you that 1986 was the last year for non-computer controlled engines in trucks over 8,600 lb GVW, per federal law (trucks under 8,600 lbs GVW were earlier). In the 1987 model year all GM one ton trucks got catalytic converters, TBI, and computer-controlled distributors. Maybe trucks over 11,000 lb GVW still had carbs and vacuum advance.
#40
Which ones? Trucks maybe, which were subject to less stringent emissions requirements than were cars. I can tell you that 1986 was the last year for non-computer controlled engines in trucks over 8,600 lb GVW, per federal law (trucks under 8,600 lbs GVW were earlier). In the 1987 model year all GM one ton trucks got catalytic converters, TBI, and computer-controlled distributors. Maybe trucks over 11,000 lb GVW still had carbs and vacuum advance.