Helping reading these spark plugs (1 Viewer)

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Nov 29, 2016
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So as I mentioned earlier, I am new to these things. I just pulled the plugs out of the engine. Obviously I have carbon on these, which is a no no, that much I know. There also seems to be some sort of stalagtite-type features growing on it. Not sure what it is, but to explain if the picture don't show is that it's a grayish growth extending only on one side of the plug's ground electrode.

They 2-6 seem to have some oil residue on the threads, 1 is pretty clean.

1 is on the right end of the photo. Two photos just to show each side.

Thank you!

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hi judger , for what i see : 1-2 too rich or/more burnig oil , 3 low fuel or too much air , 4-5-6 same as 1-2

burning oil ....need to know from where it arrives

would be better to see those plugs front side to be more accurate....
i am at home with laptop not the best to watch photo , sorry

these plugs are old ? so it is better clean them , then reinstal and ride a little and check again ...
before if you can check the "anticipo": the time of firing before the tdc also check the distibutor contact gap
sorry but i don't know how you call it
cheers
 
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I literally just got a compression gauge in the mail today so I haven't been able to do anything in that area. I'm getting an extreme exhaust smell constantly, to the point where I have to shower after I drive it, otherwise I'm not allowed in the house :). @tornio I can take another photo if that would help. I purchased new plugs and will put those in.

@brian I haven't measured the valves yet. Would out of tolerance valves cause this too? Or are you thinking it needs a top end rebuild?
 
Worn valve guides/seals can be a couple of several causes of plugs looking like this. Worn rings (reason for compression request) can also cause this. Since these motors are old, and more than likely close to needing rebuilt, the valve guides/seals and rings are three very likely culprits, and very possibly a combination of the three. The valve adjustment won't cause this.

Don
 
Okay thanks. So IF the compression test comes back okay I can assume it's a cylinder head rebuild?

Something doable at home or do I need a machine shop to do it?

Thanks!
 
Along with a compression test you may find a need to do a leak down test. This is something I have never done, so you probably will find more knowledge elsewhere (you tube?). If your compression test results are bringing up questions, then a leak down test may confirm what the compression test is pointing towards.

Don
 
You can replace the valve stem seals without pulling the head, and your deposits look like oil ash from some light oil burning. Do a compression test and/or leakdown test, and go from there. How many miles are on those plugs?
 
Thanks, I'm not sure how many miles are on the plugs as I just bought it in Nov and I've probably only driven 10 miles in total.

I will do a compression test this weekend and then a leak down test too probably.
 
Okay so compression numbers are in: (Edit this was from a cold motor, I just read that i should have warmed it up prior to tests, I will redo and also do a wet test).

C1: 140 (Made me hopeful)
C2: 90 (Getting sad, but maybe....)
C3: 70 (tears welling up)
C4: 60 (Snotty ugly little kid cry)
C5: 100
C6: 130

Joking aside, overall not good, or from what I've read.
Reconfirmed twice (I didn't do a wet test).

So now I do a leak down right?? I've never done one of those either, any specifics beside what I saw on youtube in particular with the F engine that isn't covered in the manual?

Are these numbers indicative of anything preliminarily before I do a leak down (I don't have a leak down tester yet).

Thanks!

Judge
 
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Those aren't great numbers. But... Did you do the test correctly? You already said it was a cold motor. All spark plugs removed? Throttle all the way open? Good battery? Engine cranked over 5 or 6 times at least? Is your valve lash adjusted correctly?

If "yes" to all those questions, then definitely put a teaspoon of oil down the spark plug holes and retest. Also, you say you've only driven 10 miles since Nov. How much was it driven before that? If it has sat for awhile, you may have some rings sticking. Try driving it a bit. Also, a lot of people claim Marvel Mystery Oil down the spark plug holes will help free up the rings.

Good luck!
 
Okay thanks. By throttle open do you mean no choke? Should I take the air cleaner off? Also valve lash, what's that?

Battery good and all the sparks were removed.

I don't know if it was even driven by the PO, he only owned it a couple of months and sold it because he lost his job, but I don't think it was driven.

I will try to MMO if the tests come back poorly.

Thank you again!
 
"Throttle open" means foot to the floor on the throttle pedal while cranking. Definitely remove the air filter assembly so you can see down the carb.

Earlier in this thread, checking the valve clearances was mentioned. That is the same thing as checking valve lash. You can search here on Mud to find several ways of adjusting or measuring the valve lash (clearance). There's lots of debate, but I find the easiest way for a beginner is to set the engine to TDC and check the valves that are open. Rotate the engine 360* and check the other valves that are open. .008 for intake and .014 for exhaust clearance. From front to back, it is EIIEEIIEEIIE. If you have valve clearances that are too tight, the valve will open early and stay open late and will definitely affect compression. Not knowing what the PO has done, it is definitely worth checking.
 
Alright! Great thanks. I'll do that. Thanks for the info.
 
Okay so I was able to do another compression test with a hot engine.
The numbers:

1 - 150; 185
2 - 140; 160
3 - 120; 145
4 - 120; 145
5 - 125; 170
6 - 150; 185

I think much better. Now am I correct in assuming that this doesn't indicate a problem with the bottom end? There was smoke coming out of the number 2 cylinder when I removed the plug.

I didn't have the time to do the valves yet (two little ones take time). Is it possible that a valve adjustment can fix any of these numbers? Or does it look like the valve seals would do it?

Is there a trick to getting to the engine crank bolt?

Thanks!
 
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I'm I the only one that thinks his engine is just carbon fouled because of running rich, neglected tuneups and not running it up enough?

Give it a tuneup ... cap, rotor, wires, timing, points/condenser, adjust valves, fuel filter, air cleaner, clean out pcv and adjoining hose, new plugs NOT champion plugs

Champion plugs imho run too cold... could also be an issue imo
 
Alright, so I've done almost all of that minus the valves. I just put in NGK plugs. I cannot replace the parts of the dizzy as I have a Delco Remy hei dizzy in. Unless those have servicible parts, in which case I will replace what I can.

I haven't done new wires yet but will.

Is there any additive I could use to get rid of the carbon? Marvel? Seafoam? And would I put it in the gas or the oil a bit?

Thanks for the help, this is my first real attempt at an old motor and I don't have any local knowledge sources, so you all have been great.
 

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