Has anyone asked yet? How much did your timing change?
Detonation after distributor cap install.
- Thread starter kaj750
- Start date
Bee1971
Well-Known Member
The old cap was part of the problem - Center rotor button contact on cap is melted that contacts your rotor
The new cap is correct
What does your rotor look like - Is it melted also
Can’t see the model number of that ignition coil
What are your running for an ignition box or module
The new cap is correct
What does your rotor look like - Is it melted also
Can’t see the model number of that ignition coil
What are your running for an ignition box or module
Last edited:
kaj750
Well-Known Member
I didn't see any change at all.
No ignition box. Wiring for the coil I took out and this one all come from factory harness and distributor.
I pulled out the old coil and wired this one up exactly the same.
Found this interesting: I turned the engine over until cylinder one was at top dead center. The rotor was pointing to where cylinder 1 is shown, on the dist, in the diagram below:
The way the car was before, the spark plug wire for cylinder 1 was going to number six, on the dist, in this diagram. All wires were in the correct firing order after that.
The seems crazy to me. The car's been parked for a number of weeks, so I could be wrong. But I even wrote the number one on the distributor cap where that wire was going so I'm pretty sure I'm remembering it right.
Could this even be possible?
I'm rerouting fresh spark plug wires according to the diagram above and will start the car to see how it runs.
I swear I've built multiple cars from the ground up. None of them have been older than 10 or 15 years so I don't know I'm having so much of a problem.
1 Wild R/T
Well-Known Member
1 & 6 are 180 apart... When the engine was first assembled the distributor was installed 180 out & rather than correct the distributor someone moved the wires... No biggie...
Your old cap was junk... I've seen caps like that before where the engine ran like crap... Adding timing made the engine run better... Putting a new cap on means you need to pull timing out in order to run right...
Bee1971
Well-Known Member
One more thing to add
Something caused that cap to melt
No ignition box ? Not even a Factory Mopar ECU
So looking at that distributor cap , could this be an all in one distributor ? That would still make it a CDI Ignition system type distributor
We need more information on that distributor or pictures
Thanx Scott
Something caused that cap to melt
No ignition box ? Not even a Factory Mopar ECU
So looking at that distributor cap , could this be an all in one distributor ? That would still make it a CDI Ignition system type distributor
We need more information on that distributor or pictures
Thanx Scott
Last edited:
1 Wild R/T
Well-Known Member
The center button/electrode is made of carbon rod, if it gets any side load, like instead of installing the car straight down instead sliding it sideways and the rotor sideloading the button, the button fractures... Now instead of the spark transferring directly from the center electrode of the cap to the rotor it has to jump a gap... When every cylinder fires.... Typically caps get replaced because the eight outer electrodes wear.... They see one spark every eight sent through the center electrode.. And they are made of brass or aluminum... When the center electrode is damaged it gets eaten up pretty quick...
Bee1971
Well-Known Member
Thanx , appreciate that
But what I am trying to find out first is
He mentioned factory wiring and distributor - You have to have an ignition module or box from the factory correct - He mentions none
That cap will not fit a factory distributor
That is a distributor cap for a Mallory HEI or CDI Ignition Type Distributor
That Yellow Accel 8140 Ignition Coil (1.4 Ohms) WILL NOT WORK with that type of distributor , requires a (.6 Ohms CDI Coil) and will cause that type of heat melting - I have seen it before
That is all I am trying to find out first
Peace Scott
But what I am trying to find out first is
He mentioned factory wiring and distributor - You have to have an ignition module or box from the factory correct - He mentions none
That cap will not fit a factory distributor
That is a distributor cap for a Mallory HEI or CDI Ignition Type Distributor
That Yellow Accel 8140 Ignition Coil (1.4 Ohms) WILL NOT WORK with that type of distributor , requires a (.6 Ohms CDI Coil) and will cause that type of heat melting - I have seen it before
That is all I am trying to find out first
Peace Scott
Last edited:
1 Wild R/T
Well-Known Member
Expand the thread to see most of what I wrote...
I really think this is stuff that overwhelms someone who is new to our part of the hobby.... He doesn't know what he doesn't know...
Last edited:
kaj750
Well-Known Member
I put the wires back the way they were originally. Having them in the "right" place had everything firing crazy and popping flames everywhere lol
Take timing away now that cap is functioning better check. Will try.
The rod in the center is definitely broken. I'm thinking probably happened when I took it off or otherwise moved it around. One of the retainer springs were really hard to get on and the distributors slid to the side a couple times. Very sure I broke it off.
Yes. I'm pretty sure I broke the thing off myself.
I believe in my first post I included a picture and/or description that distributor. It is a Mallory. I will check back with the part number.
**Edit: I just mentioned that I replaced a Mallory cap with a Mallory cap. I guess it was inferred that it's a Mallory distributor
Bal res?
1 Wild R/T
Well-Known Member
If you want the wires in the proper locations (Which is what I would want) you need to remove the bolt & clamp mounting the distributor, lift the distributor a little then rotate the rotor 180 degrees... (It only drops in two ways) Then put it back together with the wires by the book...
As you are probably aware the crankshaft rotates two full rotations for one rotation of the distributor (and camshaft) So the piston is at TDC when the rotor is pointed at tower #1 & tower #6... But it's either at TDC on the compression stroke (When you want spark) or at TDC at split overlap between the finish of the exhaust stroke & the beginning of the intake stroke.... (If it fires at this point it will backfire through the carb)
And Bal Res is Ballast Resistor which limits the voltage to the coil...
Bee1971
Well-Known Member
Your Quotes
A. So. Car ran fine before I started all of this and *all* I did was swap to a new distributor cap.
B. I just remembered I swapped out to a different coil. I thought I researched to make sure it was the same ohm rating, but maybe not.
A. So. Car ran fine before I started all of this and *all* I did was swap to a new distributor cap.
B. I just remembered I swapped out to a different coil. I thought I researched to make sure it was the same ohm rating, but maybe not.
kaj750
Well-Known Member
That's the plan, if this runs right now that I have everything back how it was when I started. I don't like having band-aid fixes, like moving wires 180 away from normal.
kaj750
Well-Known Member
Update:
I found top dead center on cylinder number one. I was told the wider end of the rotor should be pointed towards cylinder one. It was not. So, I pulled the distributor out and kept messing with the intermediate shaft, for lack of better term, until the distributor set The way I was told. Car still backfired.
I then placed the spark plug wires as in the diagram below. Now the car turns over without backfiring and almost wants to run. I'll mess with the timing until it starts and runs. I think it's fixed. We shall see. I only get to work on it on weekends, so we shall see.
I feel like at top dead center the contact side of the rotor should have been pointing to cylinder number one with spark plug wire number one in that spot on the cap. But, whatever, it seems to be working.
I found top dead center on cylinder number one. I was told the wider end of the rotor should be pointed towards cylinder one. It was not. So, I pulled the distributor out and kept messing with the intermediate shaft, for lack of better term, until the distributor set The way I was told. Car still backfired.
I then placed the spark plug wires as in the diagram below. Now the car turns over without backfiring and almost wants to run. I'll mess with the timing until it starts and runs. I think it's fixed. We shall see. I only get to work on it on weekends, so we shall see.
I feel like at top dead center the contact side of the rotor should have been pointing to cylinder number one with spark plug wire number one in that spot on the cap. But, whatever, it seems to be working.
It's pretty easy. Pull the #1 plug. Bump the motor with the starter with your finger in the #1 plug hole. When you fell pressure stop. Now move the crank the rest of the way and stop at 15 degrees before TDC. Now you are on the compression stroke at 15 BTDC. Align the #1 cap position to the rotor. Look at the pickup coil. Move the distributor slightly to align the pick up coils raised portion with the closest reluctor tooth. Rotor should still be pointing to to the #1 plug location on the cap but may not be perfectly centered. Follow these steps and the timing will be plenty close enough to run.
Doug
Doug
1 Wild R/T
Well-Known Member
You didn't need to touch the intermediate shaft... That
s why I didn't mention it.... Now that it's been changed set the engine back on #1 TDC on the compression stroke... And aim the intermediate shaft like this...
Then install the distributor with the rotor pointing to about 5 O-Clock
s why I didn't mention it.... Now that it's been changed set the engine back on #1 TDC on the compression stroke... And aim the intermediate shaft like this...
Then install the distributor with the rotor pointing to about 5 O-Clock
1 Wild R/T
Well-Known Member
The problem is he moved the intermediate shaft.... Sure, it'll run with the wires set to where things are now, but he stated he wants it set to OE... So put the intermediate shaft in the OE position...
Geoff 2
Well-Known Member
Kaj,
The engine will run with the #1 in any one of the eight available positions' as long as the rest of the leads are positioned accordingly. The factory has a 'preferred' position, but it makes no difference to the operation of the engine as to which location #1 lead is in.
This doesn't explain how detonation started....
The engine will run with the #1 in any one of the eight available positions' as long as the rest of the leads are positioned accordingly. The factory has a 'preferred' position, but it makes no difference to the operation of the engine as to which location #1 lead is in.
This doesn't explain how detonation started....
kaj750
Well-Known Member
It does not. But seeing how the cap and coil are all I changed, I assume it's the coil, based on the above advice.
Sooo ...
Going to put the stock coil back on.
I guess I will then re-align the inter shaft and aim rotor as recommended.
Then I'll Google "pickup coil" and "reluctor tooth" though I'm 99% sure I know what they are, given the context, just didn't know the terminology Lol
I always thought older stuff would be simpler. I definitely prefer working on my other cars. I understand all of them.
Similar threads
