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MG MGB Technical - Reading Plugs

As I ready myself for a 900 mile journey, I pulled the plugs on my 66-B and found that #1&4 plugs are the normal non-sooty grey plug that seems to burning good. #'s 2&3 seem to burning a dry black sooty color, if it is one of the carbs causing this, which one would it be? Also, I have been running the NGK Plug, should I go back to the Champion-N9Y?
Thanks
Steve C.
Steve C.

Steve-
If I were you I'd check the oil level in your dashpots and the cleanliness of your airfilter elements. I would like to debunk an old myth about the Original Equipment B Series engine. When equipped with an intake manifold that gives the incoming fuel-air mixture a straight shot at the intake ports (such as the Original Equipment intake manifold), the inner cylinders do not run richer than the outer cylinders. In reality, the pressure waves in the siamesed intake port that result from the 180° throw difference of the crankshaft have a definite influence on fuel-air mixture separation and fuel condensation in the arriving fuel-air charge in the siamesed port, and this is what creates the impression that the inner cylinders run rich. The so-called “rich mixture” in the inner cylinders is in reality the consequence of the problem of interplay between the resultant stuttering flame propagation and the condensed (reduced atomization) of the gasoline caused by the return pressure wave. The color striations in the carbon deposited in the combustion chambers that resemble sand ripples on a beach indicate interrupted flame propagation in cylinders #2 & #3, while the combustion chambers of cylinders #1 & #4 are much more evenly colored and grade out from the spark plug to the opposite wall of the combustion chamber.
Steve S.

Thanks Steve, the air-filters are rather old and I will replace them, any thought on K&N and what about the plug brand. I am making the Blueridge Parkway trip from Lex to mm-460 to the end, about a three day trip the way I am doing it. Hope your well and thanks
Steve C.
Steve C.

Steve C,
Personally I would stay with the NGK plugs and follow the advice from Steve S regarding the filters and dashpot oil.

Opinions vary on the K&N filters.
Again personal experience tells me they offer an advantage in that they can be washed and re oiled.

Pete.
Peter Thomas

This thread was discussed between 10/05/2008 and 11/05/2008

MG MGB Technical index

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