A great deal of the traffic on the Stationary Engine Mailing
List over the last two months has been on the subject of the
Tri-State Gas Engine and Tractor Show at Portland, Indiana:
preparation for the show and impressions afterwards. As it must be
one of the largest engine shows in world, it seemed an ideal place
for a meeting of those whose normal method of communication is via
a computer keyboard, so we traveled, from England, Australia,
Canada, and from coast to coast of the United States, by commercial
jet, private plane, truck and car to meet, mostly for the first
No one went away disappointed, and much as I would love to pass
on some of the comments made about the meeting (votes are not all
in yet as most of the Australian contingent are still traveling
homewards as I type), I must bear in mind that technical
information is more sought after than show reports, and pass on
instead some of the expertise which has come to light in other
‘threads’ of discussion.
The subject of the ‘finish’ on an engine is one which
crops up regularly and frequently stimulates a lively exchange, to
which the usual outcome is to leave it original, to shine it up to
a perfection not even seen in the factory–or anything in between.
It’s an entirely individual preference, and the variety, as in
the choice of engine, is one of the many things which adds interest
at a show. However, at some stage, almost everyone needs to paint
all or part of an engine, and the following advice surfaced from
those around the world who have tried and tested many different
I have found that body filler is best for deeper holes as it has
more body and strength. Most spray putty will separate in layers if
applied too thick and is best used in thin layer coats. One way is
to use the body filler, then smooth it back with a sander with
maybe 100/200 grit and the use of a light layer of body putty which
can be smoothed a lot easier with finer paper.
You can get glazing compound at most automotive supply houses to
use as a filler. Sand it, put on a good heavy coat of primer and
then paint only after the primer has cured. The paint will flow and
do a great job.
Glazing compound is fine for filling in paint shop size
holes–but Icing will work much better in a rough casting. An added
advantage is that it sands easily can be sanded about 15 minutes
after it’s applied!
Prime first, then fill. Use Icing (or a similar product), then
paint using a good automotive paint with a hardener in it. It’s
okay to prime before filling but do NOT use an etching primer under
the filler. This primer contains acid and your filler won’t
hold on it very well. Don’t bother to sand after priming. You
will be sanding after using the Icing and then priming again prior
to applying the paint. Primer is not always necessary if you use
the right kind of paint, but, on rough cast iron, your finish will
look better when primed.
I routinely use the damp proof red primer over rusty iron that I
have given a good wire wheel brushing. The red primer really helps
seal that clean iron and gives a smoother paint job.
‘Hardener’ is a product sold by automotive paint
companies that makes the paint tougher after it dries. It also
helps prevent gasoline from harming the paint. You can’t save
paint to which the hardener has been added. Make sure to save a bit
of the paint without the hardener in it to use for touch up.
The key to a durable finish is curing time. I let mine sit at
least a week between coats. I always use glass fiber filler for the
first layer. You put it on a little rough and after six hours of
drying I sand it with a rotating sander and 60/80 paper. After
this, I take Polyester filler and smooth it up, two layers of spray
putty then let it dry for at least a week.
The next week sanding, sanding and sanding again (you must have
a lot of patience). When the engine body is perfectly smooth, I
give it a last layer of primer and sand it with 600 paper. After
spraying the engine with a quality brand paint, you can see
yourself in it like in a mirror.
Whatever products you choose, make sure to follow instructions
on the can carefully, as many of them have harmful fumes. Remember
that all this advice comes from different people, and their own
experience of engine restorations. Hopefully you will find some of
the tips of use in your own restorations.
The Stationary Engine Mailing List, an Internet mailing list
receiving e-mail at a central computer at ATIS (Antique Tractor
Internet Service), welcomes input from collectors of all levels of
experience. Send comments to: firstname.lastname@example.org.