Help needed analyzing spark plug condition
Thread Starter
Le Mans Master
Joined: Apr 2004
Posts: 7,106
Likes: 38
From: Newark DE
John
I JUST walked back in from the NAPA store who I had get me in the NGK B4 plugs.
I really wanted to try the non-resistor plugs but I would have searched to see if they had an extended tip model in the non-resistor plug if I saw your post earlier.
Oh well.......
I never had a problem with the standard tip plugs before this so we will see what happens.
after this winter on my L76, I no longer have the stock ignition wires. I figured at the time that since it would be so easy to swap them out while I had everything apart it was the time to do it rather than finding out I needed to do it in another 6 months or a year later and it would have been much more difficult. I went with Duke's recommendation on the Delco 508N wires rather than go with the repro wires that looked stock with the correct markings since I've seen posts of horror stories on the repro wires - a few I think from you?? Wasn't there an NCRS event you had to help someone swap out like 2 or 3 sets of wires until you got 8 wires that worked right on the repro's?
I JUST walked back in from the NAPA store who I had get me in the NGK B4 plugs.
I really wanted to try the non-resistor plugs but I would have searched to see if they had an extended tip model in the non-resistor plug if I saw your post earlier.
Oh well.......
I never had a problem with the standard tip plugs before this so we will see what happens.
after this winter on my L76, I no longer have the stock ignition wires. I figured at the time that since it would be so easy to swap them out while I had everything apart it was the time to do it rather than finding out I needed to do it in another 6 months or a year later and it would have been much more difficult. I went with Duke's recommendation on the Delco 508N wires rather than go with the repro wires that looked stock with the correct markings since I've seen posts of horror stories on the repro wires - a few I think from you?? Wasn't there an NCRS event you had to help someone swap out like 2 or 3 sets of wires until you got 8 wires that worked right on the repro's?
Burning Brakes
Joined: Mar 2004
Posts: 1,108
Likes: 4
From: Plano Texas
Barry, I've looked at the pics of your plugs and see no problem IMHO. However, the #4 plug is suspicious enough to warrant replacement to one that matches the others. However, I would go with the 45S plugs and move forward. Have you checked the resistance of your plug wires with an OHM meter? I would, just to verify they have no problems. I'm a big supporter of spiral-wound plug wires simply because they are more reliable and won't break down.....plus they give you radio suppression. Pertronix makes a great set of black non-marked wires for your application. I've got them on both the 59 and the 62 with no problems.
Have you checked your points dwell with the engine running? You may not be getting the coil saturation you need to give the best spark. Your dwell should be around 30 degrees.
Good luck!!
Have you checked your points dwell with the engine running? You may not be getting the coil saturation you need to give the best spark. Your dwell should be around 30 degrees.
Good luck!!
Thread Starter
Le Mans Master
Joined: Apr 2004
Posts: 7,106
Likes: 38
From: Newark DE
coves
I put new ignition wires in over the winter - they are the Delco 508N which are suppresion wires. The reason I'm changing out the R45 plugs I also just put in over the winter is there is a possibility that between the higher suppresion wires and the resistor plugs that it may be causing a miss I'm getting because of a slight voltage drop. I'm replacing the R45 plugs with NGK B4 non-resistor plugs.
Dwell is perfect at 30 with no variance - nice and steady
I put new ignition wires in over the winter - they are the Delco 508N which are suppresion wires. The reason I'm changing out the R45 plugs I also just put in over the winter is there is a possibility that between the higher suppresion wires and the resistor plugs that it may be causing a miss I'm getting because of a slight voltage drop. I'm replacing the R45 plugs with NGK B4 non-resistor plugs.
Dwell is perfect at 30 with no variance - nice and steady
Le Mans Master
Joined: Jan 2002
Posts: 8,913
Likes: 283
Barry, check your wires with a Volt Ohm meter.
Also check under the dist cap for the green funk disease on the terminal contacts.
If the firewall fuse block cannon plug is week, and a power interruption at the main red feed wire is happening, this can cause a sputtering in the idle or a miss.
My L76 never had a miss problem or misfire unless the coil was taking a leave of absence. The coil masked itself as a fuel issue, etc.
I run the pertronix I, never had a problem with it in 6 years. If you are nervous about is breaking down on you, just carry a spare dist. A non tach dist (reman) with points ready to go is around 35.00 at the parts store. I keep one in the back under the rear cargo cover, in the box. IT would take all of about 10 minutes to change. Time it by ear, and drive it home.
I am running accell suppression wires (8MM), accell coil, and NGK B4 plugs. Carb is jet at 65 in front, 76 in the rear, 8* vac can, and pump gas. I also found that the idle mixture screws like ½ - ¾ of a turn out for the 30-30 and the LT-1
Mark
Also check under the dist cap for the green funk disease on the terminal contacts.
If the firewall fuse block cannon plug is week, and a power interruption at the main red feed wire is happening, this can cause a sputtering in the idle or a miss.
My L76 never had a miss problem or misfire unless the coil was taking a leave of absence. The coil masked itself as a fuel issue, etc.
I run the pertronix I, never had a problem with it in 6 years. If you are nervous about is breaking down on you, just carry a spare dist. A non tach dist (reman) with points ready to go is around 35.00 at the parts store. I keep one in the back under the rear cargo cover, in the box. IT would take all of about 10 minutes to change. Time it by ear, and drive it home.
I am running accell suppression wires (8MM), accell coil, and NGK B4 plugs. Carb is jet at 65 in front, 76 in the rear, 8* vac can, and pump gas. I also found that the idle mixture screws like ½ - ¾ of a turn out for the 30-30 and the LT-1
Mark
Thread Starter
Le Mans Master
Joined: Apr 2004
Posts: 7,106
Likes: 38
From: Newark DE
Mark
wires are new
dist cap and rotor are new - even had doubts about them so I swapped them out for my older ones which are known good.
firewall connections are perfect, clean, and tight
coil is on my list of items to check after swapping the plugs to the NGK B4's. A buddy loaned me a spare coil that is known good to check to see if it helps
I will NOT run an electronic conversion kit, picked up a spare set of points and condendor today when I got the plugs just in case for when I get to them on my list (after the coil)
the new wires are the AC 508N as per recommendation by SWCDuke
carb jetting is all stock spec, original vacuum can (works fine as tested when distr, was rebuilt)
It can only be the plugs being resistor plugs with the new wires, coil going bad, points went bad (i doubt as they are less than a year old and less than 1,000 miles but anything is possible), or valvetrain issue.
I'll check each item out one at a time
wires are new
dist cap and rotor are new - even had doubts about them so I swapped them out for my older ones which are known good.
firewall connections are perfect, clean, and tight
coil is on my list of items to check after swapping the plugs to the NGK B4's. A buddy loaned me a spare coil that is known good to check to see if it helps
I will NOT run an electronic conversion kit, picked up a spare set of points and condendor today when I got the plugs just in case for when I get to them on my list (after the coil)
the new wires are the AC 508N as per recommendation by SWCDuke
carb jetting is all stock spec, original vacuum can (works fine as tested when distr, was rebuilt)
It can only be the plugs being resistor plugs with the new wires, coil going bad, points went bad (i doubt as they are less than a year old and less than 1,000 miles but anything is possible), or valvetrain issue.
I'll check each item out one at a time
Drifting
Joined: Apr 2004
Posts: 1,303
Likes: 36
From: Allen Park Mi
I can't speak on Duke's behalf... but he seems to be all about OE equipement...
i highly doubt he would have recommended a specific set of wires if there was going to be any worry about not being able to use OE style plugs.
i highly doubt he would have recommended a specific set of wires if there was going to be any worry about not being able to use OE style plugs.
Drifting
Joined: May 2005
Posts: 1,307
Likes: 10
St. Jude Donor '09
Barry, just backing up a little bit you indicated there was a misfiring occurring. Why do you think the source of the problem would be the plugs? Were these the same type that were being used also prior to the misfiring?
Maybe the source could be dwell setting, the carburator issues you have been having, maybe the dist., or something else simpler then removing/replacing plugs (they are a bit of a pain to change).
Just wanted to add "food for thought" to speed your diagnose.
John
Maybe the source could be dwell setting, the carburator issues you have been having, maybe the dist., or something else simpler then removing/replacing plugs (they are a bit of a pain to change).
Just wanted to add "food for thought" to speed your diagnose.
John
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Thread Starter
Le Mans Master
Joined: Apr 2004
Posts: 7,106
Likes: 38
From: Newark DE
John
instead of retyping all over again (I type with 2 fingers only so it takes me a while!
) please see my new thread I just started.
It's called:
"Update on high RPM missing problem".
i explained my reason in there on why I swapped the plugs out
instead of retyping all over again (I type with 2 fingers only so it takes me a while!
) please see my new thread I just started.It's called:
"Update on high RPM missing problem".
i explained my reason in there on why I swapped the plugs out
Le Mans Master
Joined: Jan 2002
Posts: 8,913
Likes: 283
Barry, I would check the plug wires anyway. New or not, there could be one with to much resistance.
I would do that after you switch to the B4's and the problem is still present.
I tried to my hearts content to get points to not spit above 6000 RPM, and just gave in to the dark side, and installed the pertronix. It does not misss a beat to 7500 RPM. Not trying to sell you on the idea, just my experiance. That was 6 years ago, and dialing in the dist was probably beyond my knowlegde at that point in time.
Another over looked item can be the coil and balast resistor wires. May check them over for a good solid contact.
Is it just one cylinder that is falling off, or is it a miss effecting all cylinders?
Just trying to throw out some food for thought.
Mark
I would do that after you switch to the B4's and the problem is still present.
I tried to my hearts content to get points to not spit above 6000 RPM, and just gave in to the dark side, and installed the pertronix. It does not misss a beat to 7500 RPM. Not trying to sell you on the idea, just my experiance. That was 6 years ago, and dialing in the dist was probably beyond my knowlegde at that point in time.
Another over looked item can be the coil and balast resistor wires. May check them over for a good solid contact.
Is it just one cylinder that is falling off, or is it a miss effecting all cylinders?
Just trying to throw out some food for thought.
Mark
