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87 Waggy spark plug engine problem pictures!!

I was going to bring up multi spark, but was hesitant to write a book of my own ;). The one way the old points type system was superior, is most would double spark whether you wanted them to or not, nature of the beast. A combination of spring load and durability and most points bounced at least once.

Then when electronic ignition came in manufacturers were quick to offer multiple spark boxes. The down side is the plugs don't last nearly as long.

The resistance in plugs; different manufacturers or even different varieties from the same manufacturer vary wildly. Something I figured out a long time ago, the Renix ignition module seems a little finicky about resistance between the distributor cap and the plugs. And even more so between the coil and the distributor cap. I've got a lifetime supply of plug cables left over from my racing days. I've tried all sorts of types and configurations (equal length, unequal length etc.). Mostly butt dyno, all I was really looking for is something that idled really nice. A standard ohm (carbon core) cable between the coil and the cap and solid (or coil "0" ohm) copper core cable worked the best from the cap tp the plugs, with OEM Champions.

Have you ever checked out the line loss between your ignition switch and the ignition module? On all the Renix I've had, it wasn't major but noticeable. I never did the math (ohms law) but one volt of line loss is a significant amp loss. And coils are typically (relatively) high amp. Want more spark, run a wire (twelve gauge) straight from the starter relay lug, to a 30 amp relay and switch the relay with the ignition feed to the ignition module. No more line loss and less voltage flux. Lack of good spark isn't generally a Renix problem, the opposite actually, the high voltage spark is a little on the hot side and tends to travel odd paths (short out) easily. A little hotter spark can only help your fouling problem. Poor mans hot plug, open the gap up tp 45-60. The down side is the poles are close in the Jeep distributor and you may start arching inside the cap. Lots of ways to tweak it a little.
 
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Found this:

1.) AIR-FUEL RATIO

The required voltage decreases with the increase in richness of the air-fuel ratio. However, if the air-fuel ratio is too rich, the required voltage increases due to the cooling down of the electrode. The ideal air-fuel ratio is considered to be 14.7:1.

2.) COMPRESSION PRESSURE

The required voltage increases proportionally to the increase of cylinder pressure. Higher voltages are required to cause sparking under higher cylinder pressure.

It may be wise to consider a ‘colder plug’ when the compression ratio is increased.

The gap, too, needs to be adjusted to a smaller size to accommodate higher cylinder pressures.
Click to expand...

So based on that, at a reduced compression (due to engine wear), I should have plenty of voltage and might be able to increase the OEM gap and or use a hotter plug!!!
 
8Mud said:
A little hotter spark can only help your fouling problem. Poor mans hot plug, open the gap up tp 45-60. The down side is the poles are close in the Jeep distributor and you may start arching inside the cap. Lots of ways to tweak it a little.
Click to expand...

Both of those make a lot of sense, I had nearly a 50 gap on my 50,000 mile platinum bosch plugs and a good 30,000 on the rotor and cap, when the engine starting randomly dying. New Cap and rotor fixed the problem but then it came back quickly, and the fouled #1 and #2 issue came up. But they were Autolites instead of Bosch (the Bosch were level hotter, and the gap was wide to too wear). So the colder and tigher Autolite gap fouled after no time at all. Then I replaced the valve seals, and got jump from 200 miles to 1600 miles before one of the Autolites fouled.

If I go to back to a hotter plug and a little larger gap, I my be OK for a good while.
 
cruiser54 said:
NGKs, maybe one heat range hotter than stock.
Click to expand...

Which NGKs?

This one is 1 level hotter than Champion copper, and the same as the Bosch I am testing.

NGK V-Power Spark Plug Part # 7373
 
cruiser54 said:
Try it. Standard NGK Coppers one heat range hotter should be fine.
Click to expand...

Are you suggesting the 7373, or one step hotter than 7373?

The 7373 is listed at AA as one of the two best OEM Copper plug choices.
 
Ecomike said:
Which NGKs?

This one is 1 level hotter than Champion copper, and the same as the Bosch I am testing.

NGK V-Power Spark Plug Part # 7373
Click to expand...

I was wrong, had it backwards, the NGK 7373 that is currently listed as the best match by the parts houses, for Renix 4.0, is 2 levels colder than the Bosch, and one level colder than the Champion!!!! WTH!!!???

http://www.sparkplugs.com/Automotive-c134.aspx
 
Update. I am now pretty sure all OEM crossovers are Bosch #8 the hottest, Champion #9 the mid range, and NGK is a #7, the coldest range. Champion numbers are the reverse and they do not cross or match directly.

That would explain why most people have trouble with Bosch missfires, they are way too hot for their engines and heavy feet, LOL, as most of them have great compression (I suspect).

In my case I may need to move up one notch to a Bosch #9 heat range for my two weak cylinders.

I did an ohms test on the plugs I have to test the core resistance of the plugs I have, and I was :eek: shocked!!!

My used Bosch platinums measure over 20,000,000 ohms!! I am wondering what new ones read (IIRC they did read under 20,000 ohms), and wondering if that was why they fouled???? But I have 4 of them, so I think these were the working plugs in 3,4,5 and 6 when I first started on this issue.

The new Champions read 43,000 ohms :eek:

The new Bosch Copper Superplus read 6,700 ohms

The New and used (the recently pulled original #1 and #2) Autolites single platinum read 5,200 ohms.

Wish I new what NGKs read, but I don't have any.

8mud, this makes your topic of wire resistance even more interesting!!!!
 
OMG & WOW, so much for the great Champion plugs, I just opened the box of one of the 3 new ones I bought, and it has a split personality,
hasta

it is missing 1/2 side of the entire ceramic inside the spark plug!!!!:eek:

And the missing ceramic is not even in the box!!!
 
Resistance is Futile, LOL.

What are the Different Champion Resistor Types?
November 3, 2012
"R" Type: Most Resistor spark plugs feature a standard "R" type Resistor. Most Champion "R" type Resistor plugs are Champion SAC-9 suppressors. These extremely reliable resistors are formed from strontium carbonate, aluminum oxide and copper oxide powders. The resistance of a plug with SAC-9 suppressors are capable of combating typical RFI, but cannot be accurately measured with typical low voltage ohmmeters.

"Q" Type: Uses a wire wound inductive coil (or electromagnetic suppression) to reduce RFI without negatively affecting ignition performance.

"X" Type: Have a special Resistor to meet more stringent RFI requirements.

To avoid a reduction in performance, Resistor types should not be used interchangeably. Use of a non-OE Resistor type could result in engine damage and end plug life.

At the moment the spark jumps the gap it causes a high frequency burst of energy, known as RFI (radio frequency interference). RFI, as its name suggests, creates static on your radio and interference with other electronic equipment, including the vehicle’s on-board electronic control units (ECUs).

Resistor plugs were developed in the 1960s to suppress some of the spark energy, thus lowering RFI to an acceptable level. Most resistor spark plugs use a monolithic resistor, generally made of graphite and
glass materials, to filter the electrical voltage as it passes through the center electrode.

Since resistor type plugs actually “resist” some of the spark energy, non-resistor type plugs actually deliver a more powerful spark. It is for this reason that most racing plugs are non-resistor types. However, in most automotive applications, a resistor plug is required for proper vehicle operation. Use of non-resistor plugs in
vehicles that call for a resistor type can result in rough idling, high-rpm misfire, and abnormal combustion.


http://www.sparkplugs.com/learning-center/article/226/what-are-the-different-champion-resistor-type
 
I just order some plugs to experiment with

Pilot Nitrode Nickel Spark Plug
SKU# SP-NP21
Item# PILSP-NP21
$8.99


E3 Nickel Spark Plug
SKU# E3.48
Item# E-3E3.48
$5.95
BOS4418P.jpg



Bosch 4418 FGR8DQP Single Platinum Spark Plug
SKU# FGR8DQP
Item# BOS4418
$6.26 1
BOS4419P.jpg




Bosch 4419 FGR9DQP Single Platinum Spark Plug
SKU# FGR9DQP
Item# BOS4419
$6.26


:)
NGK 7373 FR5 Nickel Spark Plug
SKU# FR5
Item# NGK7373

They are copper core, as are most them above, if note all when you really dig out the specs.
 
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