Re: [FWDLK] Quandry - Fouled Plugs in 354 Hemi

["Bill Long" <big.bill@xxxxxxxxx>]

TShaw10686 wrote:

> My 56 Imperial, which is still under restoration, starts quickly, does
> not
> smoke but the plugs foul with oil (and seemingly gas).  I had it towed
> to a
> local garage where a recommended mechanic checked it over a couldn't
> find
> anything seriously wrong.  He suggested I install an exhaust system
> (old
> system had been removed), and fix a broken heat tube (from exhaust
> manifold to
> auto choke on carb).  His thoughts were that the lack of heat and back
>
> pressure was the culprit.
>
> I have done all the above with the same results. I have also changed
> the plugs
> (for the third time), installing the same plug used by a friend in the
> same
> (354) engine.
>
> I am at a loss as to what to do next and would appreciate any and all
> suggestions. The engine starts easily and runs OK for a while but then
> stars
> to make a "pop" sound, noticeable at the mufflers, as the RPM's
> increase.  I'm
> confused as to why the plugs would foul but the engine doesn't smoke.
>
> Confused In PA
> Tom Shaw - 56 Imperial

   Tom,
   I can only state from my own personal experience with a 392 Hemi, but
the problem sounds familiar, so forgive me if repeat things you have
already checked.
   Do you have any oil in the spark plug tubes? If so you will have to
remove the rocker arm (valve) covers. Look at the bottom between the
flange for the cover and the front and rear valve spring. There you
should find a hole about 1/4" in diameter. These are the drain holes
that let the oil flow back down into the oil pan. If these holes are
clogged, as they usually are, oil will pool, or flood the top of your
head,valve train and of course, the spark plug holes. When the oil can
drain down you no longer have an extra oil pan in your valve covers.
   Before you put the spark plugs back in, check the following:
1. Clean the spark plug seat on the head and both inside and bottom of
the spark plug tube. This is for proper heat transfer.
2. Do NOT use gaskets, the spark plug tube replaces them.
3. Check the condition of the rubber seal between the spark plug tubes
and the valve cover. If it does not seal oil fumes can leak and
contaminate your spark plug wires causing them to crossfire.
4. Verify your spark plug and wire type. You should have resistor plugs
and solid wires. I have tried resistor wires and they worked fine until
I put the wire covers back on. They just don't like captivity.

I hope this can help.

Bill Long
Baltimore, Maryland
1958 Imperial Crown Convertible