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["RCMerritt" <rcmerritt@xxxx>]

Thoughts from George Riehl:

Many an old time mechanic has used the spray of water into a running
engine to dislodge carbon deposits. This has been done a number of times on
not only gasoline engines but diesels also. Over rich carbs, injectors, bad
valve seals, worn valve guides and low grade fuels will deposit carbon into
the cylinders and on top of the pistons. Since water is hydrogen and oxygen,
it can produce a very slight gain in horse power. It also turns into super
heated steam that results as a "scrubber" for the internal parts of the
engine.
Detonation occurs when the compression ratio is increased from internal
deposits and the "after glow" of the deposits that ignite the fuel before
the piston reaches it's proper timing sequence (spark plug firing). Changing
the timing by rotating the distributor to reduce this condition does not
eliminate it as to lack of sound. It is still present. This results in poor
engine power and more fuel waste and adding more deposits to the chamber
from the unburnt fuel.
Many years ago, water injection systems were sold from auto parts stores
to help keep late thirties and very early 40s cars (during the WWII) running
because of the poor quality of fuel and non detergent oil which added to
build-up in the combustion chambers even though the compression ratios were
in the 6s and low 7s. In higher compression engines, water injection was
used not only to reduce deposits but to increase performance and run cooler
internally. Of course, care must be taken to obtain the proper "injection"
of the water, too much can hamper the "burn" of the fuel and actually short
out a plug.
Done in a careful way, good results can be had. But other bad maintenance
factors have to be considered and repaired. One good source of a problem is
the bad vacuum advance on the dist. and the weights inside of the dist. Oh,
and I might add, use distilled or rain water as there are no minerals to add
to the problem.