Unpleasant Surprise - Spark Plugs

Well after popping on the new radiator hose i decided to check the spark plugs as i was planning to do a full service tomoro, i knew the plugs would need replacing but did not expect them to be this old!:

This one was quite oily though which is a bit worrying as maybe the rings in that cylinder are worn, it was the spark plug second from the back but the car does not smoke black atall...

They look like they havent been changed in a loooong time and the nodes are very worn, the plug gap is far too big.

Im goin to pop in new ones tomorow but which plugs should i use? my Catalytic converter is gone and i have a 76mm straight through exhaust so should i fit NGK BCPR6ES-11?

ouch those must be some good quality plugs if they lasted so long

those are platinum (or irridium) tipped plugs, clean them up, reset the gap and pop them back in..

expect to pay around R150-00 a plug if you want to replace them with platinums again..

oh ya, and as the manual states, never clean them up with a wire brush, you will create conductive paths and have elusive misfires..

Hi 300sx, theres no way in hell im putting those rusty spark plugs back in lol:P even if it means paying R150 each for platinum tips haha, i must have new ones.

But why does it state in the manual that without the catalytic converter you should use the BCPR6ES-11, because i know those are normal spark plugs and cost about R50 each, i dont mind paying R150 each for platinums, i just wanted to know if it will really make a difference and why would the manual say what it does.

Thanks

is your cylinder head cracked?
why does those 2 spark plug have rush like that???

Hi AEP886, my cylinder head isnt cracked as far as i know, it does not use water apart from the leaky coolant bottle, and inside the area where the spark plugs fit look all fine, no visible cracks or damage, i think it was just residual moisture that rusted them over a long period of time because it is the 2 outer spark plugs that were rusty.

but im more concerned about the oil on the 3rd spark plug to the back, im worried that the one cylinder has worn rings or lost compression, the engine has 250 000km on the clock so it is possible, but i cant see the car smoke atall

its your money mate.. 🙂 personally i have cleaned plugs worse looking than those up on import motors.. the whole idea of platinums is that they last 100k or more (lifetime on a car in japan) ,the platinum you see imbedded in the tip and earth electrode virtually does not erode from the spark.. if it does not have physical damage to the tip and does not misfire, there is just not any reason to replace other than for aesthetic value.. in any case within a few thousand k's water (rain, ect) leaking into the sparkplug well will rust them again..

i dont think its a question of MUST use the BCPR6ES-11 on non catalyst models, its merely that you can use the cheaper , quicker deteriorating plugs because there is not catalyst that can get damaged if a plug starts misfiring and raw fuel goes through the cat..

i would say check Head Gasket!!! and see

compression test while plugs are out.

i agree will 300sx. if you do change use BCPR6ES which come with a 0.8mm gap, 1.1mm on old coil packs can cause missing

Hi guys, i dont have a compression tester guage, but perhaps i will buy one tomorow if it is not too expensive, i would like to just put in BCPR6ES just to see how it goes.

How do i do a compression test exactly? i must unscrew all of the spark plugs, leave the coils unplugged, put my foot flat to open the throttle all the way, and then must i just turn on the ignition key to let the starter crank the engine? then i must just write down the values of each cylinder to compare?

Remove the fuel pump fuse as well.

considering our conditions and the fact that it is turbo I would honestly rather fit a 7-range plug.

BPCR7es about R30 each

Only go to a colder plug if you need.

1 bar or over I use 7's

Well i bought a compression tester from Suburban spares today for R150, took it home, screwed it into the 1st cylinder, unpluged the feul pump fuse, all the spark plugs were out and all the coils unplugged. so i put my foot flat on the throttle and cranked it..... and NOTHING! the gauge didnt even move, dont know if i did something wrong of if its such a cheap; gauge that it did not even work, anyways i thought i would leave it for now and i put in some new BCPR6ES plugs and started her up, it started first time and idled perfectly without any missing, but i notice when the car is cold it really drives crap, it will miss and stutter around 2500rpm, it makes it a nightmare to pull away from the stop street up the road which is on an incline. When the car is warm it seems to go away completely and it will also idle fine and turbo still boosts 0.6 etc.

I did notice that the car is very heavy on feul and if i rev it high you can smell feul, i was thinking maybe im overfeuling and that is causing the stuttering when cold? or maybe its my one cylinder which had the oily spark plug.

I dont feel like having such trouble now jeez, i just bought the car and i know im going to spend money on it but i did not want internal engine trouble....

That is the life of owning a sx
my one owner sx with 140xxxkm came with free bearing knock

its not easy but worth it in the end

Ps mabe a crap compression tester

Check your spark, sounds like you could have a
- bad coil
- bad coil connection (check the connector)
- plug pag too big
- or the coil does not make good contact with the plug (check that the carbon bit did not fall out of the coils).

Ok well i checked the spark plugs now again after driving only about 20km keeping under boost and a few boosts and they all look like this:

they look a lil white but surely 20km not enough to really see, but im just relieved that they were all bone dry, even the 3rd cylinder that had a wet wet oily plug in it was now completely dry.

Like Enzio said check your coils. Make sure your gap on the plugs is right.

Thanks for the further advice guys, i will check the coils out in more detail later, its too hot at the moment outside shoo, i checked all the plug gaps before i put them in and they were all 1mm, so i left them like that, like you said rat 0.8mm would be good on the older coils but i just thought i would see how they went on 1mm.

Do any of you guys use aftermarket coils? and what do you guys do if a coil goes bad? just replace the bad coil with a working one and if so howmuch do they usually go for and where would i find one.

I found this on an american site:

http://www.frsport.com/index.php?target=products&mode=details&product_id=15958

but thats pretty expensive, they also have an awsome coolant reservoir:

http://www.frsport.com/Circuit-Sports--CS--S13-240SX-Aluminum-Coolant-Reservoir-Tank_p_1590.html

if i cant find a local workshop to make me an alluminium bottle then i may consider buying that one