According to SOR, 78-80 signal generators are a different part number than 81-87 and the early part is 1/4 the cost of the later part. I have no personal experience with 78-80 distributors, so I am relying on SOR.
how do you check dist signal generator? (1 Viewer)
- Thread starter Klunky Chris
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According to SOR, 78-80 signal generators are a different part number than 81-87 and the early part is 1/4 the cost of the later part. I have no personal experience with 78-80 distributors, so I am relying on SOR.
Interesting.. Both of mine beep in between the trigger points. both were functioning when they were removed. The trigger points "disconnect" the system.
One of mine does it slowly as well (the shaft is almost seized). I have not tried the free spinning one slowly yet.
When I do it slowly, the lapse in "beeps" is truncated. Meaning I can move to the trigger point, stop when the beep stops, then after a second the beep starts again.
The MSD actually works by an interruption in connection. That is why you can test it by grounding the Violet and green wires together and then pulling them apart as Chris was mentioning (see page 24 of this page http://www.msdignition.com/pdf/WireDiagrams/WDTN.PDF ) . To make the MDS trigger it has to break a connection...
Not to kill your head or anything
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The difference is the length of the wire from the PU to the grommet on the dissy body. The later version has an extra inch of wire to go w/ bigger diameter body. When installing the later (universal) PU in the 78-80 dissy's the extra wire just goes out against the outer body.
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Ow, my head.Interesting.. Both of mine beep in between the trigger points. both were functioning when they were removed. The trigger points "disconnect" the system.
One of mine does it slowly as well (the shaft is almost seized). I have not tried the free spinning one slowly yet.
When I do it slowly, the lapse in "beeps" is truncated. Meaning I can move to the trigger point, stop when the beep stops, then after a second the beep starts again.
Not to kill your head or anything
I only tried a 81-87 dissy just now. If the DVOM was set to ohms and beep, as long as the dissy wasn't moving it showed 160ohm and no beepy. If the rotor tip moved by the stator, then there was a beep, and a flicker on the readout. If DVOM was switched to low voltage AC, and the dissy spun at 400RPM, then it showed 600mV AC. On DC it showed just a tiny flicker, a few random mV, plus or minus. This thing is a tiny magneto, but the discharge spike is only a volt, instead of 10KV.
A '79 dissy showed the same result WRT to low speed beeping, but it wasn't mounted in the machine and spun...
Interesting..
I am super tempted to make a video of the small cap dizzy...
Would that help at all Jim?
BTW, I am using a Fluke meter... I assume it is not a piece of junk..
I am super tempted to make a video of the small cap dizzy...
Would that help at all Jim?
BTW, I am using a Fluke meter... I assume it is not a piece of junk..
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I dunno if we need help.
Klunky just needs to know the official testing protocol for the dissy coil. That's just an ohmeter test according to the FSM.
I think I understand what you're seeing for results. I dunno why those results are happening. If the ignition make a sparky at the right time, then it doesn't really matter....
Valid assumption, IMO.
For me, if it goes Beep, beep, beep. It means the signal generator is good. And that is all Klunky needs to know..
Hell, I switched to a non vac anything JDM 2F dizzy with a petronix cause I had so many troubles... So I am certainly not the best person here....
Hell, I switched to a non vac anything JDM 2F dizzy with a petronix cause I had so many troubles... So I am certainly not the best person here....
matt.mcinnes
2F-ETI
- Thread starter
- #29
Huge thanks to everyone for all the help on this.
I need to get back out there (raining now) to check this all out again and report back on results.
Obviously, a test procedure is what I need, but figuring out exactly how this all works is a great help. Even if it's useless food for our trivia hungry brains!
I need to get back out there (raining now) to check this all out again and report back on results.
Obviously, a test procedure is what I need, but figuring out exactly how this all works is a great help. Even if it's useless food for our trivia hungry brains!
Obviously, a test procedure is what I need, but figuring out exactly how this all works is a great help. Even if it's useless food for our trivia hungry brains!
Exactly, I would love to know the final answer
- Thread starter
- #32
after $150 worth of brand spanking new C-Dan Toyota signal generator..... no joy!
Turns out... it was the MSD COIL! Someone suggested that earlier but I'm too lazy to check who.
I just wanted to finish this darned thread.
BTW, the tip off that something really weird was going on was the fact that every sparkplug fired fine when held against the engine block.
When installed IN the engine block they didn't fire (evidenced by no timing light flashes) This suggested (after MUCH conversation with the VERY helpful MSD Tech Guys!) that the system had some sort of weakness when under compression... ala the coil.
I swapped in the FJ60 coil that came w/ my distributor (disconnected all the Toyota electronic stuff and just using the coil) and WHAMO! she fires right up.
ANyway, hopefully this will help the next person faced with my weirdness.....
Turns out... it was the MSD COIL! Someone suggested that earlier but I'm too lazy to check who.
I just wanted to finish this darned thread.
BTW, the tip off that something really weird was going on was the fact that every sparkplug fired fine when held against the engine block.
When installed IN the engine block they didn't fire (evidenced by no timing light flashes) This suggested (after MUCH conversation with the VERY helpful MSD Tech Guys!) that the system had some sort of weakness when under compression... ala the coil.
I swapped in the FJ60 coil that came w/ my distributor (disconnected all the Toyota electronic stuff and just using the coil) and WHAMO! she fires right up.
ANyway, hopefully this will help the next person faced with my weirdness.....
