Fouled spark plugs

[1930marie]

We flow tested the Zenith 1 on my car and all the jets checked out fine. The timing is set correctly, however, the motor is running very rich (blue exhaust). Pulling the plugs, all four plugs are identically and evenly coated with a dry dusty heavy black carbon that cleans easily with a wire brush. I only need to drive the car a few miles to get the fouled plugs. Many thanks for your help!

[John Stone]

What kind of plugs are you using?

[DJ S]

Have you conducted a compression test? Could be possible that oil is getting in the cylinder as blue smoke can also indicate the burning of oil.

[1930marie]

Champion 3x

[1930marie]

Have not done a compression check yet.

[1930marie]

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All four cylinders are fouling. I will see about a compression check today

[Patrick L.]

Blue smoke, yep, oil.

A compression check or leak down test are good tests, but, not always a good test for condition of oil rings.

[Mitch//pa]

blue = oil
black = rich
as patrick said compression test may not show anything

[mike657894]

what do you set your choke fuel valve at. the twist of your choke knob is a mixture ratio knob

[1930marie]

Originally Posted by mike657894

what do you set your choke fuel valve at. the twist of your choke knob is a mixture ratio knob

Single turn and pull to start, then three plus minutes to warm up, then I turn the GAV all the in and back out about an 1/8. Then drive it until it warms up. I think my car is very cold blooded - it takes about 15-20 minutes to warm up!

[1930marie]

Is there a chance that I blew my condenser when I changed out the plugs? The car also has what feels to me like loss of power. It feels like the motor is having power surges leaving me to think I just may not make it back to the old barn. The guy I bought the car from swears up and down this motor has had a complete rebuild (professional).

[Tom Wesenberg]

Originally Posted by 1930marie

Is there a chance that I blew my condenser when I changed out the plugs?

No, they aren't even remotely related. Hold the coil wire 1/4" from a head nut and check for a hot blue spark. Or you can also lift the coil wire out of the cap while the engine is running and check for a good spark.

[Mike V. Florida]

Originally Posted by 1930marie

... I changed out the plugs?

Did you take the plugs apart to clean them of were they new?

[1930marie]

It is looking like a professional long-block rebuild is the ticket for peace of mind and preventative maintenance. Any suggestions for a company that provides such service? I live in Oregon. Thanks!

[Patrick L.]

Have you checked to see just how much oil this monster is using ? Personally I wouldn't worry about some oil usage.
Maybe its worth a try using some hotter sparklers.

[ddweave]

I wouldn't be so quick to spend money on a rebuild. "Dry dusty heavy black carbon" doesn't sound like oil fouling - especially when you say it is the same on all 4 spark plugs. Oil fouling is - oily. Are you running an air filter? When did this problem start? Are you running MMO in the fuel? There must be more to the story.

[johnbuckley]

Running rich following fettling the carb begs the question "what was it running like before?".
If you have the fuel tap on and the motor not running does the carb visbily drip petrol? - if so maybe you just need to re-tighten the jets following reassembly ( or maybe fuel level too high) I assume you didn't forget any gasket when reassembling.

[JD 1931]

You may want to try running champ. W-18 plug, hotter plug and get them at NAPA...

[1930marie]

I have been watching to see if the motor is burning oil and I dont believe it is.

[1930marie]

Yes, I purchased a couple sets of the champion 3x (whopping $9 each) and since installing them I have cleaned the dry dusty black carbon off them nine times now.