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Lauson. My first restoration

Steve N

I purchased a small engine at a flea market last month. I was told it was a Lauson. Looks like the 55S that someone else is working on now. Color appears to look like Oliver tractor green. Has a Tillotson carb. I need an air cleaner and a fuel tank. So far has come apart easily.


John Newman Jr.

Last Subscription Date
Hello and Welcome to the 'Stak. :wave:
I believe you have a Lauson Model RSH. It is the later version that superseded the RSC.
A 55 series engine has an arm / bar cast in the crankcase that the gas tank rests on in the 55-S version that has a suction carb.
Generally, a RSC has an oil pump and the crankcase breather is on the exhaust side of the engine. A RSH usually doesn't have an oil pump (but not always...) and the crankcase breather is above the flywheel in the cam cover.
Good find. Clean her up and get her running! They are great little engines.

Steve N

best way to do it start small and work your way up, then your hooked...p.s. nice little motor..:D
At the same show, I picked up an REO Trimalawn CD25 reel mower with a Clinton cast iron motor. It looks to be complete, including all sheet metal and the original chains. I started on the small engine just to get my feet, then will dive into the mower.

Steve N

I got the engine cleaned and put back together. As John Newman says above, I think this is an RSH. The crankcase breather is under the engine shroud. This one does have an oil pump. I cleaned the oil pump, but the rest of the internals looked good with little wear. Lapped the valves and the engine has good compression. Cleaned the carb today. Still need an air cleaner and gas tank, but I'll find one eventually.

Engine will not run, no spark. I checked continuity of coils, and secondary (high voltage) side is open. I don't know if I want to put $50 into buying a new coil. I may try rewinding it myself. I'll post pics a bit later.