auzoom

Hmmm I would be interested in the truth behind this . You have to excuse the chemical dunce in me, but is the "tetra-ethyl lead" different from the "lead" in leaded fuel? Also, were you attributing the presence of the "lead" to plug failure?

Cheers

Andrew

Ottog

I pulled my plugs out my car to check and clean them just before our track day last December 8/9?. The had been in the car for 60000km and didn't have anywhere near the cardon build up that Taka or Andrew have. I stupidly broke one when removing them and had to use a second hand one from the local Mazda dealer as they didn't have any new ones in stock.

I cleaned them all up with a sandblaster - no problems. There really isn't any risk to the plugs cleaning them this way.

My new plugs have been in for 20000km now. They should probably come out and be cleaned but this close to the Nationals I'm not game - it would be just my luck and I'd break one again (LOL).

Taka,

If you are running colder plugs you increase your risk of flooding during your day to day driving. Mazda's solution to the flooding was to put hotter plugs in?

Are you using Mazda oil or another brand? or any full additives to boost octane? This may also have an impact on the degree of fouling that you will experience with your plugs.

Cheers..... Otto

takahashi

Have not update this thread for a while.

I don't have start up problem with this racing plugs and they are doing fine after cleaning for another 12000km. I just change them for tuning and now the nationals.

Graham, I puzzled at your arguments. Coz I read somewhere in RX-7 magazine (or maybe in RX-8 magazine) that they recommend change of plugs every 10000km. Not 100,000km. I backed then posted and question do we need to change that frequently and all the Australian here (especically Gomez - ) run by the book of Mazda and said it is a waste of money. Hence, I create this thread, to remind Australian to change or look after their plug early, not late.

I suspect it is the nature of rotary, since rotary has engine oil to lube the apex seal and that combination of fuel and engine oil more than likely the cause of early plug change.

People remember the early days when we cruise I ask people to remove carbon build up by revving the engine hard every now and then... that is also part of the reason.

I did not made this up.. I read them all in Japanese magazines.

Japanparts.com

Yes, the same
Yes, lead is added to petrol to raise the octane of otherwise *unsaleable* fuel
Yes, I would 100% attribute this to your early plug failure; this just does not happen on JDM vehicles running *truly* unleaded fuel ( that is: NO Lead added )
You cannot buy gasoline in Japan with lead added to it; that's been unavailable since the early 1970's

GW

takahashi

There is regulation of petrol in NSW to contain less than 0.013g/L of lead in unlead fuel. I think most unlead in much less than 0.1g/L since this is the level that is sold as half lead few years ago. Since leaded fuel has ceased in the market, it has been even easier testing as the limit is the same across the board now.

Graham I don't think they will risk penalities putting more lead than regulated in unleaded petrol. The same money can go into adversting so many more people buy their fuel.

Of course 0 is better than 0.013.... btw I thought Japan banned lead in 1986!

DMRH

***** me too when the dealer has the hide to tell you the plugs are good for 60k Km. then again they are dumb enough to believe what Mazda Australia feed them.

Platinum plugs (BUR7EQP) for the RX-7 lasted around 25k Km & I suspect the same for these RX-8 platinum plugs too.

For the record. Non platimum plugs (BUR7EQ) for the RX-7 are good for around 5k Km - 9k KM.

REgards

Japanparts.com

1975 for Japan; and Unleaded = *No Lead added*

From a Shell Oil official WebSite; ( link )

http://www.shell.com/home/content/ke..._27102006.html

"Question 4 : Will the use of unleaded gasoline extend the life of my engine components?
Answer : Yes - general engine wear and corrosion is reduced, in particular spark plug life should be greatly extended and corrosion of the exhaust system should be reduced"

My point being; what is sold your side as Unleaded gasoline does contain lead; albeit as you have noted, in far less quantity than in the past. This greatly reduces the service life of sparkplugs ( and exhaust systems ) compared with burning Unleaded gasoline as available in Japan, where there is no lead at all added to gasoline. 60,000km life on a set of premium plugs in a healthy Rotary *is* achievable running Japanese unleaded, because that fuel contains *no* lead additives at all

You'll never achieve anything like that mileage with gasoline that has lead added to it ( OZ and NZ )


Best

GW

takahashi

That is a deduced comment from the Q&A answering why choose unleaded fuel over leaded fuel (the link is from Kenya btw).

My question remains..... that does 0.013g/L of lead in Unleaded fuel a significant in terms of car damage?

Answer that with proof.

Japanparts.com

While I wouldn't use words like "damage", I have no doubt the addition of lead to gasoline significantly reduces the service life of spark plugs; you are more than welcome to disagree with me ( ! )

best

GW

takahashi

I am not having disagreement. But "significance" is an important word here.

As much so I tell auzoom that smoking can cause lung cancer. He won't listen to me and have his "minimal" cigarrette. You catch me now?

Even we know that lead will "damage" the plug. Is the amount of "damage" is enough to be noticable. There are many factor, G, as you know that engine oil in the camber = deposits we have got in the above shots of spark plugs.

StealthTL

iTrader: (1)

Maybe leaded gas should be labled "99% lead-free"......

The 0.013 is roughly 1% of the usual dose (1.3 grams of lead/gallon) that is used to boost the octane. No lead is added by refiners anymore.

"Zero" lead is impossible, given that every pipeline, storage facility, service station tank and hose, previously held leaded gas. The sludge at the bottom of tanks will be leaching tiny amounts for years to come.

I would require a picture of a 120 octane sticker on a Japanese gas pump before I would believe it. Without lead, it is extremely difficult to get over 100 octane, even if you just use the RON number, which tends to be about 4 numbers higher than R+M/2. The highest I've seen is 105 RON unleaded.

S

DOMINION

takahashi, Do you recomend I clean my plugs? or change them?
My car; new Engine @ 30K now @ 50K drive hard and worked 2 jobs at one point. Mazda told me they changed the plugs whit the new Engine. But with my last 3 cars when I had bad plugs and it was time to change I would get shacking when coming to a stop or when I take my foot off the brake peddle and I'm going to the gas peddle.
Thoughts?

takahashi

DOMINION,

After 30000miles you should really good into the plug, especially if you think you have some high end hesitation. Mind you, this hesitation does not occur on public road. That is why Mazda recommend change at 60000km. Simply because we do not drive those speed on the road.

A clean car is a good car I would say. But 30000 miles is getting a bit high.

I have seen in times and times again in RX-7 magazine in Japan, recommending changing every 10000km! Read RX-7 magazine No. 34.

viprez586

iTrader: (5)

Bumping this thread since the cleaned plug looks exactly like mine. I had a spare set at work and I dipped them in GM top engine clean for 1/2 an hour and brushed them clean with a nylon brush - minor stuff came loose but as i walk up to the parts department our seasoned tech asked "You want a spark plug cleaner?" So I gave it a shot and BAM, suckers look brand new. These spark plug cleaners are available at harbor freight and I thought about trying one out but lost interest until now.
Basically a very fine powder of silica is in what resembles a tiny sandblaster and polishes them clean.

Popped the new plugs back in and was back to chirpping them into 3rd! I'm gonna take in two more sets tomorrow and clean them so ill post pics. Even if these last 5k or even 10k, I think its worth it!

Click here for link to harbor freight!

Now bring on the flames for bumping a thread, rather then creating an entire new one.

viprez586

iTrader: (5)

First set of plugs, carbon deposits, roughly 20k.


After being cleaned.


Next set, running rich and fouled.


After cleaning.