Hi,
Im not too clear on how to read spark plugs any help would be appreciated. My motor is a b18c with 9.01 comp, the comp is as follows 180 180 150 180 i pulled the plugs and the plugs were as follows-
180 cyl's- Black rim and the tip was a whitish colour
150 cyl- was all black with this sooty residuue thing not very much of it.

now what can i gain from reading these plugs and what do they mean?

 

The black is your burning oil or really rich.

The 150 psi suggest your rings are bad.

try adding a small amount of oil to this cylinder. Then retake your compression test if the psi goes up then your rings are bad.

I would suggest doing a leak down test it will tell you more the a compression test.

 

Its what i was thinking too put i dont see any oil diisappearing also the compression 180 is pretty good for a 9.01? ive just recently had the pistons installed.
will adding oil to the cylinder damage it oor cause an excess build up of carbon or something.

 

Plug electrodes should look tan. Also, make sure you are using a plug with the proper heat range.

I call a bad valve seal on that low cylinder, if the plug is oil fouled.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSVT3K 91 C1V1C &raquo;</TD></TR><TR><TD CLASS="quote">Plug electrodes should look tan. Also, make sure you are using a plug with the proper heat range.

I call a bad valve seal on that low cylinder, if the plug is oil fouled.</TD></TR></TABLE>

i still havent corrected mmy clearnaces could that be an issue

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSVT3K 91 C1V1C &raquo;</TD></TR><TR><TD CLASS="quote">
I call a bad valve seal on that low cylinder, if the plug is oil fouled.</TD></TR></TABLE>

Thats why I meantioned to do a leak down test it will tell you where your leaking

 

i agree with nsx on the leak down test especially because you can have a bad compression ring,but your oil rings might be good indicacting oil comming from else where(like valveseals)