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opinion on these spark plugs?

Iridium plugs will not help if the plugs are getting deposits.

I need to see a picture of the insulator's color, you cannot tell a damn thing from the threads.

2 of the plugs are heavily corroded, well beyond what should be seen, indicating that you have allowed water to pool in the spark plug recesses for extended periods of time.

Plugs should last well beyond 13,000 miles. Platinum should last 75,000-100,000 miles and even the most basic copper core plugs should last 30,000 miles.

ZV
 
looks like the plugs have been in there quite along time because the electrode is so far down inside or they have a big gap. I would still think you would want the electrode sticking out more so it doesn't spark to the side. Stick with copper plugs and change ever 12k. Copper are the most effective at getting the best power. All other spark plugs will just last longer but not offer as much effiency.

 
Originally posted by: mooseracing
looks like the plugs have been in there quite along time because the electrode is so far down inside or they have a big gap.
Depending on the particular plug design, the electrode can often be recessed within the threads.

As I said already: To make any kind of accurate and reliable diagnosis we need a picture of the ends of the plugs. We need to see both the electrode tip and the condition of the insulator.

ZV
 
Originally posted by: HiTek21
Isn't oil on the plug a symptom of a bad valve seal
Oil on the plug is a symptom of oil in the combustion chamber. There are many possibilities for how it would get there, with a marginal valve seal being one of many.

ZV
 
Originally posted by: Zenmervolt
Originally posted by: HiTek21
Isn't oil on the plug a symptom of a bad valve seal
Oil on the plug is a symptom of oil in the combustion chamber. There are many possibilities for how it would get there, with a marginal valve seal being one of many.

ZV

Many Reasons? I dont think so, it is either valve stem seals or piston rings.

To OP:

I dont recall ever seeing a vehicle named a 636. I do remember a mazda 626, and the oil you are seeing was likely from a leaking valve cover gasket that wept down into the plugwire boot area. The oil on the plug threads most likely didnt get there until they were removed. I am suggesting that there was no oil getting into your combustion chamber, and that what you are seeing is a result of a common leak around that section of the valve cover.



Goodluck.

 
Originally posted by: Wags1974
Originally posted by: Zenmervolt
Originally posted by: HiTek21
Isn't oil on the plug a symptom of a bad valve seal
Oil on the plug is a symptom of oil in the combustion chamber. There are many possibilities for how it would get there, with a marginal valve seal being one of many.

ZV
Many Reasons? I dont think so, it is either valve stem seals or piston rings.
"Oil" on plugs is often not engine oil, but rather oily fuel deposits caused by an over-rich mixture. There are many potential causes for a rich mixture.

Given that all plugs are approximately the same color and have the same oily appearance, it is highly unlikely that the culpret is valve seals or shot rings since the issue is occuring across all cylinders and in almost all cases, rings or valve seals occur on only one cylinder.

As I have repeatedly said, however, no absolute diagnosis can be given based on the picture of the plugs that we have been given. There is only one thing we can do with the picture we have and that's speculate without good evidence.

Your suggestion of a leaky valve cover gasket doesn't wash because if the oil were seeping down from the plug wells (the "plugwire boot area") then the crush washer and bolt of the plugs would also show evidence of oil contamination, but those parts are clean.

ZV
 
I just noticed this...

Why on earth are you running NGK CR9E plugs in that car? First of all, the CR9E is designed for motorcycles. Second of all, it's four heat ranges too hot for the 626 (correct plug is NGK BKR5E). You put in a plug with heat range 9 when the spec is for heat range 5, and you were using a plug designed for a motorcycle on top of that.

The problem is that you used a wildly incorrect spark plug.

ZV
 
Originally posted by: Zenmervolt
I just noticed this...

Why on earth are you running NGK CR9E plugs in that car? First of all, the CR9E is designed for motorcycles. Second of all, it's four heat ranges too hot for the 626 (correct plug is NGK BKR5E). You put in a plug with heat range 9 when the spec is for heat range 5, and you were using a plug designed for a motorcycle on top of that.

The problem is that you used a wildly incorrect spark plug.

ZV

unless..... it's a motorcycle... sorry - it's a kawasaki 636
 
Originally posted by: zixxer
unless..... it's a motorcycle... sorry - it's a kawasaki 636
D'Oh! Sorry about that!

Seems to be a liquid-cooled model too. The air-cooled bikes ran rich to help keep the engine cool and I'm inclined to think that even liquid-cooled bikes run richer than cars. If the insulator around the tip is clean or only an orange-ish brown you are doing OK.

For more information on how plugs should look, try the following links:

http://www.verrill.com/moto/sellingguide/sparkplugs/plugcolorchart.htm

http://www.theultralightplace.com/sparkplugs.htm

http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

ZV
 
After reading the entire thread and finding out its a bike I say it looks normal for air cooled engine bike plug, rich. Car on the other hand, which I had though it was but was 626 just misspelled as 636, I was so ready to question the miles on that "car" 😉

Volt nice find on the last link with pics of plugs! I remember that stuff in automotive class on a poster many, many, many years ago 😱
But they are missing the ones with the green glaze to them showing coolant leaking in due to cracked head or block and bad head gasket.
 
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