Spark plug deposits

[Don W.]

Good plug is just like the other two on that side. Bad plug is the worst of the three, Best of the three is the middle plug with the front plug being a bit better then this one.

Good plugs are from drivers side. What gives? Motor runs well, oil consumption is nill. Haven't done a compression check or any other diag yet.

Since the meth comes in on the pas side could that have something to do with it?:roll:

 

[bezerk]

Re: Spark plug deposits

damn. looks like that thing didn't even fire anymore? maybe it hasn't fired for along time??? not burning the meth and doing what unburned meth does??

 

[Don W.]

Re: Spark plug deposits

You woulda thunk but the motor ran fine. Here's a pic of the other side of that SAME plug.

 

[bezerk]

Re: Spark plug deposits

you have pics of the other plugs?

 

[qbnkiller]

Re: Spark plug deposits

is the deposits on one cylinder only? How quickly will a new plug get this way? Leakdown test to ensure it isn't a ring, then look at umbrella seals.

 

[WyoSyclone]

Re: Spark plug deposits

Looks like you're using anti-seize on the threads. Any possibility you got a big goober of antiseize on the tip of the plug as it was being installed?

 

[Don W.]

Re: Spark plug deposits

Other plugs are at the shop but like I said, the other two good ones look just like this good one. The other "bad" ones are slightly better than this, the worst, one.

These plugs are over a year old with literally 100's of passes down the 1/4 on them. Again, oil consumption is virtually -0-. I think I added 1qt all year. Not counting the recent change. Valvoline 20/50 racing.

At this point I think it's the meth. I may consider repositioning the nozzle.

I'll get pics of the other plugs tomorrow.

 

[qbnkiller]

Re: Spark plug deposits

Sorry Don, but that does NOT look like something a meth kit would do. If there is more than one plug that looks that way, I would replace with fresh plugs, drive (not beat) it for a hundred highway miles, pull them and recheck for deposits.

 

[SY2455]

Re: Spark plug deposits

You woulda thunk but the motor ran fine. Here's a pic of the other side of that SAME plug.

It almost like like oil burning, how is the valve seal and valve guide for this cylinder ? Is the insulator cracked at or about the 10 o-clock position ?

 

[Don W.]

Re: Spark plug deposits

I looked with a magnifying glass and couldn't tell if that's a crack or not. Darn small if it is.

gbnkiller: Truck is on stands for a leak repair in the front dif, left side stub shaft seal. I will install new plugs and put some miles on and recheck. Not a prob. I was grabbing a straws with the meth thing. Just can't figure why the plugs would look so good on one side and so bad on the other.

I have access to a serious road racer type (not drag racer) I'm gonna check with him also.

Thanks all.

 

[Beavis]

Re: Spark plug deposits

head gasket? antifreeze?

 

[qbnkiller]

Re: Spark plug deposits

so you're saying all the plugs on one side look that bad? Did you have head work done on that side? For sure check valve guides, umbrella seals, etc. Those are oil deposits. And that crack is likely the deposit which has cracked, not the ceramic.

Do a leakdown test on that side and compare to the good side.

 

[Don W.]

Re: Spark plug deposits

Had an acquaintance who is a professional race mechanic look at these and he agrees that it's valve seals. Working on the front dif leak now, Will install new plugs, run them and report as suggested.

Thanks again...