Readers Engine Questions: Mystery Lawn Mowers & Maytag Mixtures
39/8/1: Briggs & Stratton LA One of my in-laws found this so-called lawn mower in an old building on a farmstead he recently purchased. I would appreciate any information any of your readers could contribute. The engine is a Briggs & Stratton Model LA, engine no. 37331. According to information available to me, the engine was built between 1931 and 1932.
Any information on the mower would be very much appreciated. Harlan Ternes, 5335 Fair hill Road, Bismarck, ND 58503-8019; (701) 220-7665.
A: We're betting the mower is a home-built unit. That said, the addition of a transmission (we're assuming it's geared to increase blade speed) is interesting.
39/8/2: Maytag Fuel Mixture? I have been told that chainsaw fuel mix should not be used for Maytag engines. I understand that non-detergent engine oil and gasoline should be mixed, instead.
What mix ratio of oil to gasoline should be used? Also, what weight of oil is recommended? Ron Shipley, 1110 Riley Ave., Emporia, KS 66801.
A: Good question. We've seen references ranging from 1/2-pint regular oil to 1 -pint regular oil (not two-stroke) per gallon of gas. Maytag owners?
39/8/3: Unknown Toro Engine? I'm sending along some pictures of a one-cylinder gas engine of unknown manufacture.
It has a Bosch AB33 magneto, a Tillotson clamp-on carburetor, a brass petcock in the upper part of the cylinder as a compression release and external valve springs with adjustable tappets.
It has no governor at all and must just depend on the operator's good sense not to let it over speed. It is air-cooled and has a 6-inch-diameter pulley on the flywheel side with a notch in it to wind a rope for starting. The crankshaft does not protrude on the other side. It has a stub shaft that bolts to the end of the camshaft as a power take-off (1/2-speed).
From what I can tell, it had never been repainted or taken apart until I partially disassembled it for cleaning. Other than a cleaning, I have left it looking exactly the way I found it.
I have shown it at shows, and it has generated a lot of curiosity and a lot of questions that I can't answer.
It has a brass tag on it that reads: 'Engine no. 2639 Toro tractors and golf course mowers.'
I contacted the Toro Co. in Bloomington, Minn., and they said they had no records of ever manufacturing engines of their own. Most of the engines they used were built by Lauson. I contacted Lauson, and they said they couldn't help. They don't think they ever made engines like this. Any help as far as history, use and quantities manufactured would be appreciated. I picked this engine out of the iron pile at a local junkyard for $10. All I did was rebuild the magneto and clean up the engine, and it runs great. They are still out there, if you look for them! Doug Oldenburg, 530 230th St., Homer, NE 68030.
Flywheel Forum is a place for readers to ask questions and share information on their equipment. If you have a question about your engine or tractor, please send it along to Gas Engine Magazine, 1503 S.W. 42nd St., Topeka, KS 66609-1265.
By Rusty Hopper
Hello again everyone. As some of you may already know, on May 18, 2004, we lost a great model maker - Bob Shores.
I had recently been in contact with Bob, who was getting me some of his drawings and plans for a new carburetor he built just before his passing.
The carburetor Bob designed is called the 'Minimix.' Designed for model engines, it's made from bar stock and is a mechanically self-compensating, rotary drum, throttle-type carburetor with only five parts.
I also had just purchased his book, Ignition Coilsand Magnetos in Miniature, which should be in every modeler's library.
Bob's wife, Margaret, and his family will continue offering his many fine model casting kits and his book. Contact them at: Small Gas Engines 108CarmelinaSt, Ruskin, FL 33570, (813) 645-8322, www.bobshores.com/pages/ 1/index.htm
Editor Richard Backus and I had another talk about my input into the magazine and how and where my column should be headed. We like the tips and ideas many of you have sent, and we look forward to hearing more from all of you. And don't forget to send in pictures of your model projects with a short write up about them.
I would like to use some of this space for a model-building 'follow along' where I build a model and describe the process, discussing how well the plans and drawings read out and the ease or difficulty of building a given model. This would cover everything from the time of ordering castings to the first firing.
The first model to get this treatment would be an easy-to-build gas engine from a kit. Next up might be a steam engine, followed by a conversion of some sort (turning an old air compressor into an engine, for instance). Future build-ups could even include hot air engines and multi-cylinder engines, and projects could be anything from the newest scale on the market to one that has been out for some time. Is this hobby great or what?
This month's tips for model and scale parts sources:
Joe M. Tochtrop has a model of the Economy Engine. (415) 346-6038.
Jerry E. Howell has casting kits for hot-air engines and plans for engines. (719) 579-6407.
These tips are for your thoughts only, and your fuel lines may vary.
Have a tip other model makers should know? Send it to Rusty Hopper at Gas Engine Magazine, 1503 S.W. 42nd St., Topeka, KS 66609-1265; firstname.lastname@example.org
I enjoyed your article on painting models, and I would like to share some of my painting experiences in the hopes of helping you avoid what sounds like a very frustrating experience.
First of all, any attempt to use any commercial spray paint other than Krylon has, in my experience at least, led to disappointment. The extra $1.50 a can for Krylon is well worth it.
Priming the metal is all-important - you absolutely have to have a solid foundation, or your finish is destined for failure. And before applying primer you must degrease the surface to be painted, either with Coleman lantern fuel or 99-percent isopropyl alcohol. I have had very good results with the 'rusty metal' primers from both Rustoleum and Krylon. And forget what the label says: Think in terms of days between coats, not hours. Here in Texas, I like to let painted items bake in the hot sun for a day or two (a couple of weeks is even better) after priming.
My favorite method for priming bare cast iron is to take it to the car wash (or dishwasher if the item is small) to thoroughly clean it, then let it sit out in the morning dew a few days to lightly rust. Wire away any powdery rust with old denim rags, then apply Permatex 'Extend' or any of the other high-quality rust converters containing phosphoric acid, which turns the rust black. This produces a very tough primer that is probably better than any you can spray on. Again, adequate drying time between coats or between primer and topcoat is essential, especially if the primer and paint are not the same brand.
In regards to paint applications, yes, the spray equipment makes a huge difference. For small work such as you are describing, you will obtain much better results with an airbrush than a larger spray gun.
Again, apply several thin coats, allowing adequate drying time between coats, and use an inline filter on the air line to prevent contamination of the paint stream.
For larger models or engines, try an HVLP (high-volume, low-pressure) spray gun. Choose one that has a fluid-transfer capacity of no more than 1- to 3-cubic-inches per minute (17- to 50-cubic-centimeters per minute). You will get much better results with a small-volume-capacity gun operating near capacity than with a larger gun choked down to nothing. Anything labeled 'for all types of paint' or 'excellent for latex paint' is made for painting barns, not engines.
Finally, I like to paint outside with a moderate wind blowing toward the surface I am painting. This helps to carry the paint in the right direction and helps it dry before it can run.
Once you get a coat of paint (I am assuming you are using enamel) that you are happy with, you can dry it to a hard, durable finish in your oven set at 200 to 250 F for one to three days. Don't do this with tanks that have ever held fuel! I keep the stove vent hood going until all the fumes subside. This is also a good way to speed up drying time if you are in a hurry, and the parts are small.
You mentioned that you are having trouble with paint causing valves, etc., to stick. Simply mask the parts you don't want painted with heavy grease and wipe it off (paint and all) after the paint dries
I hope some of these tips help. I am only an expert on my own experiences, but these tips have all worked for me. Keep that old iron looking and running great!
John Townsend IV 15292 Fm2728, Terrell, TX 75161
These two scale engines come from the workshop of Australian scale-engine builder Reg Ingold.
The engine above is a 1/4-scale 1885 Atkinson 'differential' engine. A four-cycle design, the Atkinson's seemingly convoluted linkage enabled it to run through all four cycles in one crankshaft revolution. A fabulous animated illustration of this unique engine (and many others) can be found on the Web at www.keveney.com
At right is Reg's 1/2-scale Mottershead. It's believed the David Mottershead Co., Manchester, England, was in business for only a year or so about 1910. Reg recently restored the only known full-size Mottershead for an Australian collector.
Contact Reg Ingold at: 37 Seaham St., Holmesville 2286, NSW, Australia; email@example.com Check out some of Reg Ingold's other scales at: www.oldengine.org/members/randmingold/index.htm