HELP! Read my plugs!

[excelguru]

I'm not much of an expert at this... please take a look at my spark plug photos (use the link below) and let me know what they're trying to tell me...

CLICK HERE

Choosing to "View Full Image" will give you a much larger photo (that's a warning to dial-up users). I am especially worried about cylinders #4 and #8 (rear of block on passenger's and driver's side respectfully). Both had a good bit of soot and oil on them - 4 is the worst. Some of the plugs seemed okay. One or two have a thick, flaky brown crust (#7 for example).

On a side note... have you ever tried to take decent photos of spark plugs? Damn difficult.

Keith

[computerworks]

Keith...is #4 as wet as it looks in the pic?
also, #7 looks like it has a broken insulator.

finally, you ARE taking baby pictures, as well, aren't you?

[KobraKarl]

XL,

Not an expert either, but that looks like good old fashoined oil fouling. hyow old are the plugs?, how long has it been sitting?

[Turk]

Keith,
How many miles do you have on this motor?


TURK

[niles]

Keith;
Need little more info:
1. how many miles?
2. Dino oil, I hope, no syn yet?
3. Your several jet sizes rich.
4 How much oil are you using? Lots of oil signs, rings possible not yet seated.
5. Are you sure you not misfiring, one( 8 or 4) looks like it might be missing?
Need to do a compression check; 4 and 8 look like rings are not sealing well at all; just be lower psi or your misfiring.

gn

[Excaliber]

#7 could be just a wierd looking deposit, if not, then a chunk is missing all right.

Over all it appears ALL the plugs are burning cold for the fuel/ratio/timing you got. Advance the timing, lean out the carb or go one step hotter on the plugs is a thought.

#4 may not represent an "oil" problem as much as a mis-fire for so long it accumulated oil deposits. The plugs appear to be fairly new as the center electrode is showing minimal wear. The carbon build up would indicate to much "putt putting around". Watch the tack and keep the rpms up above 2K or better after the engine warms up. You "lugging" that motor?

As there is potential for loose carbon in the combustion chamber don't go out and "hammer" it. That will break loose the deposits and they will stick to the plugs. But DO get that rpm up, steady and get the engine HOT. Bring it home and SHUT IT DOWN right away, don't "putt putt" back to the garage.

Plug readings are best when the engine is immediatly shut down following a decent "run" at speed and temp. Temp needs to come up and STAY there about 20 to 30 minutes AFTER it reaches "normal" to get a decent "reading" on the plugs.

,,,,not that I know squat about plugs, but I did stay in a Holiday Inn recently.....

Ernie

[KobraKarl]

Let me guess, you are doing this at 3 am........ And your gops look too wide, they look like 50 k from here.

[Excaliber]

,,the gap does indeed look a little wide,,,,,hard to tell. Wonder what is recommended for this application and what you got?

Ernie

EDIT: With "after market" electronic ignition sustem where the voltage is SUBSTANTIALLY higher than the "original" point type ignition you COULD run a larger gap, and it WILL be better than "stock". Stock was about 15 to 20,000 volts. Electronic will be 40 to 100,000 volts, much bigger "spark" and wider "gap" make for good things.

[petek]

... higher voltage and more current. (Ok, I'm pickin' nits.)

This plug reading via cyberspace could catch on. We'll need a section devoted to it (and I'm only partially kidding)!

[excelguru]

HOLY COW!

I post one itty bitty question before going to bed... then I wake up and have a TON of excellent information at my disposal. This website totally rules... really.

3400 miles on the odo... last drive was this past Saturday.

I have noticed quite a bit of "lost" power in the past few months... only getting about 430 HP at the flywheel... should be more like 530... maybe those plugs (4 and 8) haven't been hitting for quite a while, huh?

I haven't upgraded to the newer transformer-type of coil yet, still using the old "bottle-type" coil. I may change it, though. Will it really make much difference? The recommended gap with this setup is .045 in accordance with my engine builder. I have not yet checked the old plugs to see how close they match that requirement. Won't be driving it to work today... oh well... (sigh).

Keith

P.S. Taking TONS of pics of Caleb. These digital cameras are great for that!

P.P.S. I usually try to drive it like a stole it, when local law enforcement isn't within earshot.

[Steve R]

Keith,
I would start by checking some basic stuff to assess the health of the engine. do a compression check of all the cyls. They are probably ok with that kind of milage. I guess if the eng was using oil you would have said so.
Looks like the engine is running rich to me. Do you let the car idle a lot?, What carb are you running? Is the float level correct? A high float level will make it richer. Check the power vavle if it is a Holley. I'll stop babbling now
Steven
Dah, I just looked at your gallery. Oh yeah, I remember that intake. above info still valid. Just add an "S" after the above ref's to the carb

[Doug Axelrod]

Just an uneducated onlooker, but the excellence of the advice here, and the willingness to help, is just wonderful.

(Remember this during the yearly CC fund drive...)

[Mr.Fixit]

You are running dual quads, and the fuel mixture is too rich, there is a big surprise. Replace the sparkplugs, drive it hard, then pull them out and take a look. Also, you should put a capacitive discharge box on there , such as an MSD or Jacobs. It is hard to tell if your problem is oil related, or just way too much fuel, since the problem is worst on the rear two cylinders, and you have dual 4bbl's, I am guessing fuel.

[ToyCollector]

Keith, they definitely look "wet" and rich to me. All the plugs look rich. The crud on 4 and 8 looks carbon like. Is the wetness I see on the threads oily, or does it smell like gas? How does the car sound? Any popping/backfires noises (i.e. bent pushrod)? The advice to start with a compression check is sound advice, then check your timing , then fuel mixture, then tweak your iginition components if needed.

[bmalone]

I would look at the basics first. Compression test, leak down, etc. You may find a bad head gasget--I hope not, but I would start with the most basic areas. I picked up excessive carbon on a couple of cylinders due to valvetrain not operating correctly.

[Trans-Am Jim]

To perform a proper plug check, the engine should be run up hard through at least 2 gears, then shut off immediately at peak RPM. Pull over to the roadside, pull the plugs and read 'em.

If I idle my 427 for a few minutes then turn it off, I get plugs thet look similar. 2x4's, by their nature, idle too rich. When I do the above proper plug check, they are right on the money - tan.

[excelguru]

I almost feel ashamed to send such a small check to Brent each year. This website is nearly priceless to me.

I will spend the next few days doing the following:

1. Compression check
2. Leakdown test
3. New plugs (duh)
4. Drive it like a stole it, then quickly check plugs
5. Hot valve-lash check (needs to be checked anyway)
6. Timing adjustments
7. Jet adjustments

That should keep me busy for a while.

I live right in the middle of a subdivision, so driving it hard immediately before turning into the house isn't an option fo me. However... I do have a friend with a car shop located in front of a nice straight piece of blacktop... hmm...

I must admit that I don't drive it hard as often as I would like (or as often as I might like to boast). Oftentimes, I just cruise through town (oh, for shame! ).

Keith

[Excaliber]

When I was working for a Ford dealership a customer with a Chevy station wagon 454 came in. This was in the early 70's.

Fouled oily looking plugs and run on after the motor was shut off. The car was fairly new but out of warranty. Compression/leak down was good. I found a note in the "technical data books" we had about excessive carbon buildup on the Big Blocks with low miles. Recommended FACTORY solution? Pour a little WATER down the carb as the engine is running at temp. The violent reaction in the combustion chamber breaks loose the carbon, cures "run on" and detonation.

With so few miles on your car I doubt carbon buildup is a problem on yours. BUT, if you don't keep it clean, it could be in the future.

The Chevys main problem? They guy never drove it hard, EVER. With the old point type ignition he would foul plugs fairly quickly. If it's bad enough the excess gas also gets past the rings, diluting the oil. So it turns into a catch 22 situation. Thin oil, gets past the rings, fouls the plugs etc.

Ernie

[Ron61]

Ernie is right on the button about the engines not being driven to blow them out. A friend of mine bought a brand new 1964 Galaxie with the 427 dual fours and for no reason would he drive it over 55 miles an hour. It used to much gas. After about three weeks the car would hardly run and he had it towed to the Ford dealer. One look at a couple of plugs and they told him to either drive it or park it. So it set in his garage on jack stands for two years befor ehe finally sold it.

Ron

[Mr.Fixit]

Gotta stand on the throttle here and there to "clean it out" get some temp in the combustion chamber and clean the plugs. If they have too much crud on them, the crud will glaze on the plugs.