Trouble starting rebuilt 12a and timing
11-25-21, 02:04 PM
#1
Trouble starting rebuilt 12a and timing
This is an 80 with the one off ignition box and I've set the timing to what I've always done. But it just didn't wanna fire or pop and was leaving the trailing plugs soaked and leading plugs dry and ok. So i tried something I've never tried before. I swapped both leading and trailing plugs from front to rear and rear to front. And yes they were in the correct spots to begin with but it all of a sudden started to fire and pop just off of starting fluid?! What is going on here and is it something im missing with the 80 ignition setup I've never played with before?
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risingsunroof82 (11-30-21)
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risingsunroof82 (11-30-21)
11-30-21, 03:37 PM
#4
Once I get the ignition switch situation (fell apart) figured out I'm gonna try going the 180 range.... and I had the pulley off but I didn't take it apart if that makes sense? And the pulley is keyed so how would that happen? I did use a different e-shaft so could that have been it? I'll just have to make my own timing marks.
Last edited by risingsunroof82; 11-30-21 at 03:41 PM.
11-30-21, 05:26 PM
#5
yes, definitely try setting it 180 degrees from where it is now, then. i mentioned the pulley before i suggested the 180 degree thing simply because it would have been a root cause.
i've seen them with keys and without, and i have no idea what years had what. i just know some people pull them apart, unwittingly, and then run into similar issues when it comes time for the first fire, because they reassemble it wrong. so that's where my head went.
i've seen them with keys and without, and i have no idea what years had what. i just know some people pull them apart, unwittingly, and then run into similar issues when it comes time for the first fire, because they reassemble it wrong. so that's where my head went.
11-30-21, 05:33 PM
#6
yes, definitely try setting it 180 degrees from where it is now, then. i mentioned the pulley before i suggested the 180 degree thing simply because it would have been a root cause.
i've seen them with keys and without, and i have no idea what years had what. i just know some people pull them apart, unwittingly, and then run into similar issues when it comes time for the first fire, because they reassemble it wrong. so that's where my head went.
i've seen them with keys and without, and i have no idea what years had what. i just know some people pull them apart, unwittingly, and then run into similar issues when it comes time for the first fire, because they reassemble it wrong. so that's where my head went.
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12-04-21, 06:56 PM
#10
no it's stock ported.... but even if you line up the leading mark it could be on the opposite side being 180 out due to the half turn of the dizzy to every full turn of engine. Can't know for sure without a bore scope to see the rotors position.
12-05-21, 02:31 PM
#14
So since I'm a hands on and visual learner I mocked up a spare engine that's all apart. Have the rear iron rear rotor and shaft with front pulley on and turned the engine and see that it takes 3 shaft rotations to make one complete rotation of the rotors.... so this means it is impossible for it to be 180 out then right? And the rivet on the pulley when leading mark lined would put the rivet at a 7 o'clock position right? And with one shaft rotation the rotors may not be in the same chamber in the combustion phase but that wouldn't matter since all chambers are essentially the same as one another.?
12-06-21, 10:17 PM
#18
then why are these not the same as the other 1st gen ignition setups? Your arrow is facing the passenger fender when the other setups say to face the arrow to the oil fill tube? But it makes sense that it's out and I'm very thankful for your help.
12-06-21, 11:42 PM
#20
so I set the arrow to the direction of your dizzy and I did get some combustion but it however gave the sound that it was trying to fire in reverse... gave the pop then hesitation then turned a second more and the same pop with resistance.... so it's clearly timing... but the method I've only seen was pointing the dizzy toward driver while on leading.... are they different?
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risingsunroof82 (12-07-21)
12-07-21, 12:24 PM
#22
3D Printed
My apologies for what may be a brief thread jack, but is the 79 dizzy (with points) clocked to a different position than the other engines with electronic ignition? I ask because I know that on my engine the arrow points to the right (rear of the vehicle) when I'm at the yellow leading mark.
Edit: Forgot to mention that I'm running an 82 engine and dizzy in my SA.
Edit 2: Just read backwards in the thread a little and it looks like I'm not crazy. Never knew that the 79 points dizzy was clocked a different way. That's quite interesting.
Edit: Forgot to mention that I'm running an 82 engine and dizzy in my SA.
Edit 2: Just read backwards in the thread a little and it looks like I'm not crazy. Never knew that the 79 points dizzy was clocked a different way. That's quite interesting.
Last edited by Benjamin4456; 12-07-21 at 12:29 PM.
12-07-21, 03:28 PM
#23
My apologies for what may be a brief thread jack, but is the 79 dizzy (with points) clocked to a different position than the other engines with electronic ignition? I ask because I know that on my engine the arrow points to the right (rear of the vehicle) when I'm at the yellow leading mark.
Edit: Forgot to mention that I'm running an 82 engine and dizzy in my SA.
Edit 2: Just read backwards in the thread a little and it looks like I'm not crazy. Never knew that the 79 points dizzy was clocked a different way. That's quite interesting.
Edit: Forgot to mention that I'm running an 82 engine and dizzy in my SA.
Edit 2: Just read backwards in the thread a little and it looks like I'm not crazy. Never knew that the 79 points dizzy was clocked a different way. That's quite interesting.
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risingsunroof82 (12-09-21)
12-07-21, 06:10 PM
#25
3D Printed
I just read through the thread and, please correct me if I'm wrong, it sounds like you're using the 1980 ignition setup with the remote mounted ignition box (the photo would seem to indicate so)?
Assuming that's correct, this setup only lasted one year for a few reasons, one of which is a cross-talk issue that can lead to plugs firing when they aren't supposed to, although I don't think that's your issue in this case. Due to the early pre-catalytic mandate exhaust system, the ignition system in 1980 has some extra functions. The main one is that it can disable the trailing ignition under certain scenarios. This was done to keep enough unburnt fuel going through the thermal reactor to maintain a high enough operating temperature to work properly. I don't recall all the scenarios where this occurs, but I know that decel/coasting is one. I believe it is also disabled at start up until the choke switch shuts off, but don't quote me there. This is why the early cars run the tach off the leading coil, because sometimes the trailing coil isn't firing.
I'm also not sure what chassis you have this setup in, or how all your wiring is set up. The plug that controls this feature is a two wire connector with (if I recall correctly) a yellow and orange wire. If you have this plugged into something, unplug it and leave it unplugged (unless your car is fully or nearly stock). My next question would be, have you gotten a timing light on it? If not, I would highly suggest you do so. This will let us know for certain when (and if) the plugs are firing. It is also possible that the ignition box has been damaged over the years and no longer works properly, although perhaps this is a known good box, I'm not sure.
Assuming that's correct, this setup only lasted one year for a few reasons, one of which is a cross-talk issue that can lead to plugs firing when they aren't supposed to, although I don't think that's your issue in this case. Due to the early pre-catalytic mandate exhaust system, the ignition system in 1980 has some extra functions. The main one is that it can disable the trailing ignition under certain scenarios. This was done to keep enough unburnt fuel going through the thermal reactor to maintain a high enough operating temperature to work properly. I don't recall all the scenarios where this occurs, but I know that decel/coasting is one. I believe it is also disabled at start up until the choke switch shuts off, but don't quote me there. This is why the early cars run the tach off the leading coil, because sometimes the trailing coil isn't firing.
I'm also not sure what chassis you have this setup in, or how all your wiring is set up. The plug that controls this feature is a two wire connector with (if I recall correctly) a yellow and orange wire. If you have this plugged into something, unplug it and leave it unplugged (unless your car is fully or nearly stock). My next question would be, have you gotten a timing light on it? If not, I would highly suggest you do so. This will let us know for certain when (and if) the plugs are firing. It is also possible that the ignition box has been damaged over the years and no longer works properly, although perhaps this is a known good box, I'm not sure.