firing order 1-8-4-3-6-5-7-2

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Pawned

Pawned

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I have a 71 Duster 318V. I decided to change the plugs and as I hook up the wires it appears to me that the 7 and 6 cylinders are reversed.

The car has been running really nice. Is that possible with the wires hooked up incorrectly???

There is no chance that I mixed them up this time as all the spark plug wires are still in the looms and 6 and 7 are on opposite sides of the engine.

I am going to turn the engine by hand and make sure that the cap is at the 1 position and track it back
 
That is the correct firing order.
Im not sure what to say if it was running fine with them wrong
 
Any 2 plug wires reversed means 2 cylinders are not working. Not much to guess about. Sbm rotation is clockwise, #1 cylinder is drivers side front. 1,3,5,7 on drivers side, 2,4,6,8 passenger side, follow cap see where they go. Connection error is common on 5 and 7, they should cross each other from cap to plug.
 
So far so good. I am going to record what they are now. then I will redo the wires like it 'should' be and see what happens. I have the correct 1 cylinder position as when I timed it, she was firing at TDC.
Why does this happen to me. I would like to blame this on the engine rebuilder but I am pretty sure I put the electronic ignition in after I got the engine back.
 
Get the engine to TDC. Take off the distributor cap and see which terminal the rotor is pointing to. that should be #1 cylinder. Then go around the distributor cap and the wires should follow the firing order in the direction of rotor rotation in the distributor.
 
krazykuda said:
Get the engine to TDC. Take off the distributor cap and see which terminal the rotor is pointing to. that should be #1 cylinder. Then go around the distributor cap and the wires should follow the firing order in the direction of rotor rotation in the distributor.
Click to expand...

I did and that confused me even more. It was not at #1 It was at about 3:30 if it was a clock. Where #1 is at about 6:30 . It should be at 6:00 but taking into the timing setting it was at 6:30.
I have finished redoing the wires. I came in the house to cool down before I go out and try to start it
 
All its doing right now is backfiring

Need to take it apart again and start over
 
A long time ago I was told that the average properly tuned engine will fail to ignite each of it's cylinders a certain percentage of the time. As I recall it was part of ACCEL's advertising on their electronic high performance BEI ignition systems. The claim was that a higher output spark was likely to decrease the percentage of failed firings and thereby increase power. I assume the same theory holds true with multi-spark systems like the ones made by MSD.

I know that back in the 70s the best performance improvement I'd made was when I'd installed the BEI. These days I tend to run an MSD box on all of my cars.

If you did have two cylinders failing to fire there should have been a huge performance gain after switching the wires around. I hope you pulled the two plugs out and cleaned them because they most likely were not burning off any oil deposits for some time.
 
Sounds like the distributor is installed about 90 degrees off. You can get an engine to run no matter, you just have to get the wires rotated around to the right spot.
 
Likely distributor 180 degrees out. Crank makes two revolutions per one distributor rotation. TDC can be for #1 or #6, if for #1, make sure valves are closed, or at top of compression stroke.
 
KitCarlson said:
Likely distributor 180 degrees out. Crank makes two revolutions per one distributor rotation. TDC can be for #1 or #6, if for #1, make sure valves are closed, or at top of compression stroke.
Click to expand...


It is not 180 off. I never removed it from when I parked it. I am going to go out and try again, I have some ideas
 
KitCarlson said:
Likely distributor 180 degrees out. Crank makes two revolutions per one distributor rotation. TDC can be for #1 or #6, if for #1, make sure valves are closed, or at top of compression stroke.
Click to expand...

Agreed Mr Carlson dist is 180* out.

hahaha,(laughing at Myself) had to brush off the cobwebs on basic engine mechanical...
90* rod journal crankshaft, =

1 & 2 are paired
3 & 4 are paired
5 & 6...
7 & 8...

Cam lobe placement determines firing order so cyl #6 & #1 would be on compression
stroke, cyl # 5 would be exhaust stroke.

As far as I know mopar small block cams have always used the same cam lobe placement
for #1 cyl coupled with 'indexed' ignition components.

I am uneducated on mopars marine cam configurations however.
 
Pawned said:
It is not 180 off. I never removed it from when I parked it. I am going to go out and try again, I have some ideas
Click to expand...

It could have been 180 out when you bought the car, but it will still run fine.

Take #1 plug out, this is on the front of the engine drivers side.
Stick you finger in where where the plugs should be, with somebody bumping the engine over, or jumping the start solenoid with a screw driver you will feel pressure with your finger, there will be two pulses one is weak the other really pushes.

Stop when you feel it pushing hard, this is where #1 cylinder wants to fire.
Take the distributor cap off and look where the rotor button is pointing, this is #1.
Put the plug wires on starting where #1 is pointing and fire it up.
 
4spdragtop said:
#1 on rotor should point at front intake bolt on driver side
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The car was running fine when I shut it off.
I turned the engine to TDC, when I popped off the dist cap this is the position of the rotor.
I am very confused
it is at 8:30 The distributor is rotated full CCW in order to get the timing set
 

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That distributor is in way wrong. From your picture, the vacuum can should be pointing to about 8 o'clock with the rotor pointing to around 5:30. I am betting you don't have it on number one like you think. What cylinder are you calling number one?
 
69_340_GTS said:
Doesn't have to. As long as the rotor points at the terminal on the cap that is connected to the #1 plug wire (at TDC of course), it will work just fine.
Click to expand...

Yes.

Find TDC on the vibration damper. Make sure that it's TDC and not 180° off. Or remove #1 spark plug and cover the hole with your finger. Crank then engine over with a remote starter and when you feel pressure building up, that is your compression stroke. Get the #1 piston to TDC.

Now look at the distributor and see where the rotor is pointing. Make that terminal on your distributor cap for #1 spark plug wire. Now follow the direction of distributor rotation around the other terminals on the distributor cap 1-8-4-3-6-5-7-2.
 
Looks like the distributor advance is spun way around making a "by the book" position of the number one plug wire in the cap to be in the incorrect position.

Ok, so I was kinda late on that. :)
 
krazykuda said:
Yes.

Find TDC on the vibration damper. Make sure that it's TDC and not 180° off. Or remove #1 spark plug and cover the hole with your finger. Crank then engine over with a remote starter and when you feel pressure building up, that is your compression stroke. Get the #1 piston to TDC.

Now look at the distributor and see where the rotor is pointing. Make that terminal on your distributor cap for #1 spark plug wire. Now follow the direction of distributor rotation around the other terminals on the distributor cap 1-8-4-3-6-5-7-2.
Click to expand...

First, it might be a good idea to turn the distributor body about 90° CW to get the vacuum advance closer to where it is supposed to be. Looks like it's hitting the carb, or is pretty close to. Then follow krazykuda's instructions.
 
sireland67 said:
It could have been 180 out when you bought the car, but it will still run fine.
Click to expand...

I'm sorry sireland,, but a motor simply won't run 180* out,,.

Think about it,, you'd be sending spark to a cylinder thats in overlap,, both valves likely slightly open,, exhaust gases have just been pushed out,, there's little or no fuel,, no compression,, just an open intake valve to "pop" thru..

hope it helps
 
krazykuda said:
Yes.

Find TDC on the vibration damper. Make sure that it's TDC and not 180° off. Or remove #1 spark plug and cover the hole with your finger. Crank then engine over with a remote starter and when you feel pressure building up, that is your compression stroke. Get the #1 piston to TDC.

Now look at the distributor and see where the rotor is pointing. Make that terminal on your distributor cap for #1 spark plug wire. Now follow the direction of distributor rotation around the other terminals on the distributor cap 1-8-4-3-6-5-7-2.
Click to expand...

As much as I thought this was a wacko idea, I spoke with Mrmopartech on the phone and he explained it to me again.

So I tried it. Took about 15 minutes and it started on half a turn.
THANK YOU ALL FOR YOUR HELP.

Also thanks for the idea of turning it 180 to free up the vacuum advance
 
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