Still struggling with car at idle after 8 years

[jalexquijano]

Plugs 4, 5 and 6 rear carb at 3.5 turns clockwise

Edited November 4, 2023 by jalexquijano

[gundee]

We are starting to get there as far as plugs starting to look the same.

Manual says 2-1/2 turns with 17 degrees advance.

Lean them out just a little more and see how the car runs.

[Zed Head]

I have a vague memory of mentioning this in the past, but another reason for fouling plugs is oil.  Bad oil rings or valve seals.  Since you already have new seals, the only thing that's left is oil rings.  

On the plugs, pictures after they were cleaned but before they were used again would have been good.  Can't tell how much of the brown is permanent staining.

The residue around the edges of the plug body, end of the threads, looks pretty thick for such a short drive.  Looks more like oil-fouling.  

[jalexquijano]

Next step??? Clean all plugs again or new set?

[jalexquijano]

50 minutes ago, Zed Head said:

I have a vague memory of mentioning this in the past, but another reason for fouling plugs is oil.  Bad oil rings or valve seals.  Since you already have new seals, the only thing that's left is oil rings.  

On the plugs, pictures after they were cleaned but before they were used again would have been good.  Can't tell how much of the brown is permanent staining.

The residue around the edges of the plug body, end of the threads, looks pretty thick for such a short drive.  Looks more like oil-fouling.  

I only replaced valve seals in 4th cylinder.

[Mark Maras]

 I shudder when I think of the number of spark plugs you've bought over the last eight years but unless you can get them clean (snow-white porcelain) a new set will get a fresh reading (Deja Vu) and hopefully narrow this down to the fuel-air mixture or oil. Did the plugs start to load up when you were waiting for your roasted chicken lunch?

[Yarb]

I agree, Cleaning with a brass brush will not get the job done. Clean the oil off. Sandpaper all the electrodes and you have a chance.

[jalexquijano]

27 minutes ago, Mark Maras said:

 I shudder when I think of the number of spark plugs you've bought over the last eight years but unless you can get them clean (snow-white porcelain) a new set will get a fresh reading (Deja Vu) and hopefully narrow this down to the fuel-air mixture or oil. Did the plugs start to load up when you were waiting for your roasted chicken lunch?

 

1 minute ago, Yarb said:

I agree, Cleaning with a brass brush will not get the job done. Clean the oil off. Sandpaper all the electrodes and you have a chance.

Ok

[jalexquijano]

Remember rear carb is at 3.5 turns clockwise and front at 3.75 turns clockwise looking from top of the engine. Do you want me to reduce the mixture on the rear carb?

[gundee]

Lean that back carb out a bit more. Probably carbon. Should clean themselves up.

Bump that timing up to 17 degrees. Makes a difference how it runs.

[jalexquijano]

Its at 14 right now. Will i damage the engine increasing to 17 btdc?

[jalexquijano]

On 11/4/2023 at 5:54 PM, gundee said:

Lean that back carb out a bit more. Probably carbon. Should clean themselves up.

Bump that timing up to 17 degrees. Makes a difference how it runs.

Timing set to 17btdc, front carb set to 3.75 and rear carb lowered to 3.4 turns clockwise. Raced car on the highway 110 mph, few stops and couple of traffic light no longer than 1 minute idling.  Plugs 1, 2, 3,4 and 5