peculiar spark plug reading

[Al]

Hi
After a 30 minute highway trip I took out my spark plugs. They look brownish tan with a slight grey on one side and the other half of the plug is oily. I've searched here on the site but could not find an answer. I have never seen this kind of peculiarity, it really looks like two seperate halves. What would be causing this and what would be the solution?

The engine is a 383 HP Charger with stock 1968 cam, Holley street avenger 670 with 65 jets on the primaries, green accelerator pump cam, 0,031 discharge nozzle 20 inHg vacuum at idle, the idle mixture screws are 1,5 turns out. MSD 6 box with Mopar dizzy. Spark plugs are Champion RJ12YC

Any insight would be welcome.

Al

[RD]

pictures are worth a 1,000 words, got any?

[Al]

No unfortunately not. My camera is not good enough to take decent close up pictures.

If you keep the plug vertically in front of you, it's as if one half, vertically speaking, is oil fouled while the other half looks ok. Never seen that before. And while driving, idling or accelerating there is no smoke at all! Engine has a tendency to stall shortly after starting warm or cold.

[Blown70]

Every plug?

[Al]

Yes pretty consistent on both cylinder heads.

[b5blue]

Are you using intake gaskets with the valley pan? Did you put sealant on the intake bolts? Check the top of your valley pan for any oil with a clean rag, all the way back.

[Al]

Are you using intake gaskets with the valley pan? Did you put sealant on the intake bolts? Check the top of your valley pan for any oil with a clean rag, all the way back.

No intake gaskets with the valley pan but gaskacinch. No sealant on the intake bolts, only engine oil. I thought that on big blocks sealant is not necessary on the intake bolts or am I mistaken? Also no oil on top of the valley pan, checked with a clean rag as you suggested.

The spark plug reading had the same peculiarity with the stock manifold and stock ignition. Now I have an Edelbrock Performer RPM with MSD ignition and this bizarre spark plug reading hasn't disappeared. 

[b5blue]

Your problem is not what I had but oil can work it's way into odd places from the valley. I was thinking you were getting a tiny bit into your heads intake ports maybe, it can also creep up the threads sometimes. Both have happened to me recently so now I use sealant (RTV) on the threads and gaskets above and below the valley pan. Just keep it in mind. Plenty of guys don't do it and have no problem.

[firefighter3931]

I'm wondering if the PCV valve isn't bad....assuming you are running one ? How long since it was checked/replaced ?

What plugs are you running Al ?



Ron

[Al]

Hi Ron

Spark plugs are Champion RJ12YC. I'm  using a brand new PCV valve on the right side cylinder head and a breather on the driver side. The PCV is a plastic Fram one however it's not a 100% fit on the Mopar aluminium valve covers and grommet.

[firefighter3931]

Hi Al, try replacing the PCV valve and see what happens. How old are the valve seals ?


Ron

[Al]

Hello Ron, I have the PCV valve I got from Summit, they only have one model for the 383 engine. It looks like a plastic cheapo and has a tendancy to slide out from the valve cover grommet (the Mopar ones for cast alum. covers). If the PCV is possibly causing the oil fouling and is maybe responsible for my engine stalling when cold and in Reverse (or in Drive and uphill) then should I drive without PCV valve and replace it with a second breather cap or simply plug it?

I think the seals are the original ones, ie. from 1968.

Greetings
Al

[firefighter3931]

I think the seals are the original ones, ie. from 1968.

That sounds like your problem Al. If the seals are original they will be vulcanized and in some cases missing. Most valveseals over 20 years old need replacing.


Ron

[Al]

OK. Will this have negative consequences for the engine ?

Al

[FLG]

Besides burning oil it wont hurt the engine.

[Al]

 
Thanks for your replies, I greatly appreciate.

Al