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To start things off, I thought I'd take a moment to bring new readers of Gas Engine Magazine up to speed on where we get the material for these articles.

The Antique Tractor Internet Services (ATIS) Stationary Engine Mailing List is a free Internet mailing list. Questions and comments from subscribers to the list are sent in the form of e-mails, which are then electronically posted to every member of the list. With list members residing in countries around the world, someone is always at their keyboard no matter the time of day, and this means replies come in quickly. The wealth of knowledge (the width and depth are also pretty well plumbed!) that shows on the list is simply too good to miss out on just because one doesn't have a computer, and so this column was born.

Individual contributions, each marked with a bullet, come from the various list members, and it's my job to select a subject from the previous months' postings, gather relevant material and turn it into the articles you read here.

Some months a suitable subject is easy to spot, but this month was particularly difficult as the subjects ranged far and wide, covering insurance, recharging magnetos, shows, new acquisitions, plus a multitude of other engine related topics. I finally settled on a few different questions about engine finish.

And so on to the discussion that attracted my attention this month on the ATIS Stationary Engine Mailing List. As ever, the following comments reflect a variety of opinions that surfaced during this discussion.

I just brought home a Hercules 1- HP. It still has the original paint and decals on it. I cleaned it up with kerosene and it looks really nice when it's wet. Is there any way to give it a shiny finish and keep it that way?

Tire shine (or something similar) does a good job of sprucing up an engine if you don't want to varnish it.

If it was my engine I would clean it well, maybe three to four applications of Gunk applied with a soft scrubbing brush. Then I would give it two coats of Krylon clear.

That's good advice for preserving an original finish. But what about a full restoration calling for a new finish?

I got into automotive painting over 25 years ago. Over time I have settled on a combination of primers that have served me well in auto restoration. The process I follow is fairly simple, and it includes phosphoric washing of bare sheet steel, priming with zinc chromate primer, primer-surfacing with a lacquer-based primer and top coating with a good catalyzed enamel or urethane like DuPont Imron (my favorite).

I am currently working on 'slicking' two 3- HP Hercules engines, and what I use for automotive applications is not working so well on cast iron. With cast iron I first sandblast with aluminum oxide to remove any rust. Immediately following that I spray a very wet coat of zinc chromate primer, which gets into all of the crevices and holes in the cast iron. With the high humidity in North Carolina you have to spray within minutes of blasting or rust will return.

After this primer dries for a week or two I use a side grinder fitted with an 80-grit sanding disk and lightly sand the entire casting surface to remove any high spots in the cast iron. This leaves bright cast iron with low spots coated in zinc chromate primer. Following this I whip up a batch of body filler and skim coat the entire surface of the casting. Once the filler is cured the fun begins - sanding all that body filler to slick up the casting. Finally, I use a high quality lacquer primer/surfacer to get the surface ready for paint.

On flat surfaces this technique works great, but on inside radii/fillets I am having a terrible problem with the primer/surfacer lifting and not adhering to the body filler or zinc chromate underneath it. I have concluded this is due to shrinkage of the primer as its solvent evaporates. Sometimes this happens immediately, other times it happens weeks later when I think I have finished a part. I'll poke around in the fillets and find huge flakes of primer/surfacer coming up.

Do any members have experience slicking engines, and what procedures do you use and what primers have you been using? Are catalyzed primers the only solution? I have heard of some new self-etching primers. Do they have application here?

I always use glass-fiber filler for the first layer, put it on a little rough, and after six hours of drying I sand it with a rotating sander and 60- to 80-grit paper. Following this I use polyester filler to smooth it up, followed by two layers of spray putty which I then let dry for at least a week. The next week is 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-grit paper. After spraying the engine with quality paint you can see yourself in it like in a mirror.

On steel trucks I use three layers of thick industrial primer. It takes a lot of time sanding, but when you're finished it's almost ready for spraying the topcoat. Before I apply my topcoat I give it a last layer of primer out of a rattle can. This primer flows by itself and when it is dry you have one smooth surface. After a light sanding with 600-grit paper to remove the dust it's ready for the final touch.

One method for getting a good paint job on cast iron is a technique used on milling machines and other large, cast iron machine-shop equipment.

After a good washing down with solvent to remove any grease, the cast iron is treated with phosphoric acid, leaving the surface dampened with the diluted acid to dry (as best you can in a humid environment). This is followed by a thin layer of auto body repair putty. The putty is put on with a trowel or diluted and brushed on like a really thick layer of paint. This gives a really tenacious veneer that can then be sanded to give it a nice, smooth finish. This layer is never sanded through to the metal. If it is, a new layer of putty is put over the bald spot. Once it is the way you want it, prime it and paint it with automotive enamel.

It's presently show season in the Northern Hemisphere, and the World Wide Web is the ideal place to post photographs of the shows everyone has attended. This in turn inspired a series of discussions about restorations and how far is 'too far' when it comes to the cosmetic restoration of an old engine.

I have just been looking at photos of engines at the Astle Park (UK) show and was impressed by the overall quality of the engines shown. Is it perhaps that they look better in photos? No matter how much effort I put into a restoration, I can always see room for improvement after I'm done.

It would be nice to tell you that what you see is the general state of restoration in England, but to be honest I think that anyone posting to an international list only takes pictures of the best as a matter of national pride. Also, in the case of Astle Park everyone knows that the best engines are likely to be there, so people take the best restorations or rarest engines they have.

I personally see nothing wrong with the U.S. and Aussie restorations that get posted on the list, so perhaps this is universal.

I have often wondered what the word 'restoration' means. And what is over-restored? I can't say I know the answer, and I have completed engines to various stages of restoration.

I consider my Fuller & Johnson restored. It is on a nice transport, sports original paintwork (or what's left of it) and it runs like a clock. Then there's my KA Stover. New paint, no filler, pretty rough here and there but looks okay and runs fine. Next example would be the Hornsby - body filler, two-pack paint, new decals, etc. I'm happy with all of them. I think I sort of decide the character of the engine when I get it and from there decide what degree of restoration I will give it.

In my view all that's important is that your engine exhibit looks pretty clean. Engines always display well no matter what state they're in if they're clean.

The old topic is back again! Usually it comes out 'to each his/her own.' The 1908 Crossley I just finished had 1/8-inch of filler all over it under the paint. And yes, it got a new coat of filler, even though I will still get the purists who will criticize it because 'it was never built that way.' Conversely, 1 have watched non-engine people, the normal mums and dads, looking at engines at Australian rallies. They don't know what is rare or different, and they usually walk past an engine with no paint. But they always stop and have a good look at an engine that has been 'over done.'

We have found filler on the Lister diesels and on the Ruston & Hornsby diesel. Rustons were known for their quality of finish, but I was surprised that Lister, a mass-producer of engines, had the time to put filler on their castings.

Happy restorations!

Engine enthusiast Helen French lives in Leicester, England. Contact her via e-mail at: You can join the Stationary Engine List on the Internet at:

In my view all that's important is that your engine exhibit looks pretty clean. Engines always display well no matter what state they're in if they're clean.'