How often do you do it - Change Spark Plugs
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- hks_kansei
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Re: How often do you do it - Change Spark Plugs
The plugs don't need anti sieze or anything.
Hell, for a while I had an old B6 in the driveway getting rained on, plug wells were full of water for about 2 years.
Plugs came out no problem.
They were rusty from having been submerged for so long, but the threads were clean.
As far as tightening, either torque them to Mazda specs, or just tighten them by hand (ie: no handle on the extension socket, just twist it in by hand)
Once they seat, attach he ratchet and do a 1/8 to 1/4 turn to tighten.
Hell, for a while I had an old B6 in the driveway getting rained on, plug wells were full of water for about 2 years.
Plugs came out no problem.
They were rusty from having been submerged for so long, but the threads were clean.
As far as tightening, either torque them to Mazda specs, or just tighten them by hand (ie: no handle on the extension socket, just twist it in by hand)
Once they seat, attach he ratchet and do a 1/8 to 1/4 turn to tighten.
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Re: How often do you do it - Change Spark Plugs
if the car is dríven at least once a week and an hour it should not need a trickle charger. My car does not always get dríven weekly other times daily.
Seriously - the idea about service is checking the owners manual- all the KLM's or frequencies are there no one needs to guess. If people want to spend more money than is necessary its their choice.
Seriously - the idea about service is checking the owners manual- all the KLM's or frequencies are there no one needs to guess. If people want to spend more money than is necessary its their choice.
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Re: How often do you do it - Change Spark Plugs
My old BP engine using the $4 plugs, I replaced them every 10K.
All the cars I service now are MZR engines, so iridium plugs good for 90-120K depending on vehicle.
All the cars I service now are MZR engines, so iridium plugs good for 90-120K depending on vehicle.
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Re: RE: Re: How often do you do it - Change Spark Plugs
Rocky wrote:It doesn't look remotely like what I am used to with previous cars where you just unclip the HT leads and unscrew the plugs.
This looks like you have to undo four 10mm bolts on the plastic things on two of the plugs. Everything is connected together like a monkey puzzle.
It may look more difficult than it is.
This is what my 2001 audi looks like under the plastic cover... basically a spaghetti factory.

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Re: RE: Re: How often do you do it - Change Spark Plugs
Nevyn72 wrote:I'm now at 114K Km and have a new set ( I scored a box of 4 from the US for A$32 delivered!) ready to go in with the next oil change @ 115K Km.
So when are we changing it?
I'm keen

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- Rocky
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Re: How often do you do it - Change Spark Plugs
project.r.racing wrote:My old BP engine using the $4 plugs, I replaced them every 10K.
All the cars I service now are MZR engines, so iridium plugs good for 90-120K depending on vehicle.
So, PRR - what do you think about the more expensive plugs - e.g. Iridium etc - for a standard NB8B.
Any significant benefit apart from the longer life?
My car spends little time at consistently high revs. Vast majority of the time it is up and down between 2000 & 4000 RPM.

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Re: How often do you do it - Change Spark Plugs
I just checked the MX-5 service on the manual albeit for US miles/klms - spark plugs (R) 50,000 klm frequency 2 years. I just replaced NGK6953 BKR5E-11 4 of $23.80. I am betting many drivers do less than 10.000 klm per ann. Its a waste of money to buy fancy plugs. When plugs are removed the idea is also to check them. Many guys are going to replace a little less frequently and it will not matter a toss. The NGK plug is fully fit for purpose.
As an aside having owned many older cars the plugs today and engines are far superior than +30 year old vehicles. We used to throw plugs in the bin regularly due to being carboned up and practises like spark plug cleaners were the order of the day- now we give them the flick because costs and longevity are the norm.
As an aside having owned many older cars the plugs today and engines are far superior than +30 year old vehicles. We used to throw plugs in the bin regularly due to being carboned up and practises like spark plug cleaners were the order of the day- now we give them the flick because costs and longevity are the norm.
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Re: How often do you do it - Change Spark Plugs
Yes MM, in the past I changed my plugs every 10,000 Klms religiously and often gapped and cleaned them in between that.
Plugs were easily accessible and did not have other electrical stuff hanging off them.
(except my FIAT 124 CC Coupe on which plug No4 was almost in the firewall and could only be accessed by squatting with feet on the shockie towers and using an articulated spark plug spanner.)
Plugs were easily accessible and did not have other electrical stuff hanging off them.
(except my FIAT 124 CC Coupe on which plug No4 was almost in the firewall and could only be accessed by squatting with feet on the shockie towers and using an articulated spark plug spanner.)

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Re: How often do you do it - Change Spark Plugs
Rocky wrote:(except my FIAT 124 CC Coupe on which plug No4 was almost in the firewall and could only be accessed by squatting with feet on the shockie towers and using an articulated spark plug spanner.)
That bloody Fiat engine! the plugs go in at about 4 degrees from vertical, but to look at them in their holes they look vertical. And it is soooo difficult to get the thread started because of trying to guess that stupid angle. There may be some angle backwards or forward too. I never figured it out from the 4 plugs I did on a friend's car. Grrr.
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- Rocky
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Re: How often do you do it - Change Spark Plugs
I once had a spark plug socket for this job - DOG only knows where it is now.
The NGK site suggests the BKR5E-11 plug has a 16mm hex. Anyone know for sure what size spark plug socket it uses?
Workshop Manual is of course no help.
The NGK site suggests the BKR5E-11 plug has a 16mm hex. Anyone know for sure what size spark plug socket it uses?
Workshop Manual is of course no help.

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Re: How often do you do it - Change Spark Plugs
Up to you. regular plugs versus iridium is personal choice.Rocky wrote:project.r.racing wrote:My old BP engine using the $4 plugs, I replaced them every 10K.
All the cars I service now are MZR engines, so iridium plugs good for 90-120K depending on vehicle.
So, PRR - what do you think about the more expensive plugs - e.g. Iridium etc - for a standard NB8B.
Any significant benefit apart from the longer life?
My car spends little time at consistently high revs. Vast majority of the time it is up and down between 2000 & 4000 RPM.
I be using a 5/8in spark plug deep socket. Close enough to 16mm.Rocky wrote:I once had a spark plug socket for this job - DOG only knows where it is now.
The NGK site suggests the BKR5E-11 plug has a 16mm hex. Anyone know for sure what size spark plug socket it uses?
Workshop Manual is of course no help.
I used BKR6E-11s on my Astina BP engines many moon ago. Which is the same size as your BKR5E-11s. And use a 5/8in spark plug deep socket.
- Rocky
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Re: How often do you do it - Change Spark Plugs
Thanks PRR. I eventually found a spark plug socket that fitted but no extension and T piece to fit the socket so I went out and bought another socket that fitted the extension I had.
I gave my ex-mechanic some credit for not over-tightening the plugs or coil-overs as everything was easy to undo. What a pleasure.
The 22,000 klm plugs were fine but I had the new ones so I put them in. On the basis of this I have made a note that plugs only need changing every 30,000 ks - like it says in the Handbook.
(and this time I have put the tools in the boot so I can find them next time)
I gave my ex-mechanic some credit for not over-tightening the plugs or coil-overs as everything was easy to undo. What a pleasure.
The 22,000 klm plugs were fine but I had the new ones so I put them in. On the basis of this I have made a note that plugs only need changing every 30,000 ks - like it says in the Handbook.
(and this time I have put the tools in the boot so I can find them next time)

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Re: How often do you do it - Change Spark Plugs
Buy a toolbox rather than carrying your tools around in the boot of the car.
- Rocky
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Re: How often do you do it - Change Spark Plugs
I know where you are coming from - all that extra weight banging around in the back.
As a young bloke I used to carry a toolbox around in the boot (I was actually capable of working on the cars of that era) but I eventually realised that I never used it so tossed it out.
I always carry a handful of tools - couple of screwdrivers, couple of pliers, multi-grips & some zip ties - just in case.
I might ask Santa for a bigger toolbox as all my tools are currently spread over several boxes which is how I lost track of my original 16mm spark-plug socket & bits.
As a young bloke I used to carry a toolbox around in the boot (I was actually capable of working on the cars of that era) but I eventually realised that I never used it so tossed it out.
I always carry a handful of tools - couple of screwdrivers, couple of pliers, multi-grips & some zip ties - just in case.
I might ask Santa for a bigger toolbox as all my tools are currently spread over several boxes which is how I lost track of my original 16mm spark-plug socket & bits.

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- greenMachine
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Re: How often do you do it - Change Spark Plugs
Tool roll FTW! No rattling, minimal space.
I have just bought myself a two-piece tool box + roller cabinet. Magic! A place for everything, and everything in its place ... for a day or two anyway

I have just bought myself a two-piece tool box + roller cabinet. Magic! A place for everything, and everything in its place ... for a day or two anyway



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