I found an "Outboard Marine Corporation" (OMC) walk behind push mower at an auction.  The mower deck has a name "Ryan Lawn Care" and the Briggs and Stratton engine was date coded for 27 October 1980.  I was attempting to revive the old 3 horsepower engine and at the same time, provide a restoration of the vintage mower.  I was interested in the history of the mower itself.   

My research for the OMC/Ryan lawnmower does not bring up anything about the Ryan company (or the product division).  If you have read my guide concerning the brand names of mowers (Lawn Tractors - What's in a name?), you'll know what I am talking about.  Anyway, the OMC/Ryan lawnmower has a model number of B-500 and was manufactured in Galesburg, IL. 

The possibilities of OMC/Ryan being acquired by Jacobsen, Toro, Lawn-boy, Cushman, and/or Ryan has led me down several different paths.  One of the hardest things is to obtain Owner's Manuals and Illustrated Parts Lists (IPLs) for old mowers.  My search has led me to the conclusion that just about anybody or everybody wanted to supplement this business with a mower division.  It seems that if your business needed a money boost - just start manufacturing and selling lawn mowers. 

There are were several concerns of the mower.  First, did I want to restore the mower or preserve the mower?  Secondly, would making the mower operational be of any use?  Finally, how much time and money would this effort be worth?  I realized that by preserving the mower, I would actually be able to use most of the the mower deck's original paint.  The decals on the deck were worn, but could be preserved for the future.  I never heard the 3 hp Briggs and Stratton (B&S) engine run.  I was curious if she would run at all.  I was confident that it could run if I took care of a few problems.  And finally, time and money were not really an issue - as long as I thought I knew I wasn't going to make any money on trying to sell this mower.

The Briggs and Stratton Engine

Even though I was told that the engine had low compression, I checked it with a compression gauge.  After four pulls, the compression nearly reached 120 psig.  As I looked over the engine, there were some things that had to be initially inspected.  I removed the 5-side air cleaner and found a mess.  The B&S uses a foam (soaked in oil and then squeezed) air filter.  The foam filter (Part Number 5009D) was caked with dirt and crude on the inlet side of the air filter.  As I removed the foam filter, it crumbled in my hands and also collapsed.  You could actually squeeze the foam filter and compress it to nothing.  I could understand why the engine was maybe running rich and possibly thought to have low compression. 

The next thing was to inspect the internal part of the cylinder head.  I removed the spark plug and found it to be coated with the dark, oily crude of running a rice mixture.  The internal part of the cylinder head is where I really wanted to inspect.  I removed the cylinder head bolts and removed the cylinder head.  The cylinder head gasket was filled with carbon deposits.  In fact, the top of the piston, valves and cylinder head were coated with carbon deposits.  By scraping and cleaning, the carbon deposits were removed from those areas.  I obtained a new cylinder head gasket and installed the cylinder head.  I also purchased a new spark plug.  Spark plugs are such cheap insurance to ensure a decent running engine. 

The oil that was removed from the engine was thick and black.  I wouldn't even guess as to the last time it was changed.  About this time is when I usually go into some sort of rant about taking care of these little engines.  Not only does the oil provide lubrication for these air-cooled engines, but it also provides cooling to the internal parts.  Granted, it's only a splash lubrication - but still, a little bit of cooling.  That's why it is so critical to change the oil in an air cooled engine. 

I removed the mower blade from the engine and I had another wonderful surprize added to my list.  There is a mower blade adapter that attaches the mower blade to the engine shaft and it was broke.  The key (a half-moon) was also missing from the blade adapter.  The previous owner must have struck an object that caused the mower blade adapter to break the key.  Instead of replacing the adapter, the single mower blade bolt was over-tightened so that the blade would not come loose during operation.  Again, I just could rant and rave about the safety of such an ignorant practice!  Anyway, I was now going to have to find a blade adapter.  I was going to try sharpen the mower blade and attempt to use it for the preservation of the mower. 

Thus far:

• purchased a new cylinder head gasket
• purchased a new spark plug
• purchased new 30w engine oil
• purchased new mower blade adaptor and key

The Mower Deck (Ryan/OMC)

The mower deck (hereafter, called the deck) really didn't need a lot of love.  The top side of the deck could use a good washing and waxing.  The right rear wheel was broken at the hub.  The left rear wheel had a 'toe-out' problem and needed to be straightened.  The underside of the deck needed to be scrubbed and cleaned.  The handle bar needed new bolts and knobs to hold the middle section together.  I would also need to find a deflector shroud to prevent flying debris from coming out of the deck.  It should be easy to get the items I needed.

NON-COMPLIANT engines/mowers must be operated with extreme care.  There is no operator safety device on the mower.  The operator could start this engine and literally put their hand or foot under the deck with the blade moving at high speeds.  Most of the safety devices were installed because of idiots doing just that.  Lawsuits followed and then came the safety devices.  I don't encourage using a non-compliant mower on a daily basis.  But just like the Ford Model A's that don't have seat belts or air-bags installed - just be careful in the operation of such equipment. 

Ryan and Lawn-Boy were made in the same factory.  The steel mower deck is a 4505 Lawn-Boy deck.  The Lawn-Boy green and the Ryan red colors made a slight difference.  They both used a 4-cycle engine on this particular deck.  I have researched various web sites that deal in vintage parts and the basic parts diagram is the same for both mowers.  Lawn-Boy is now owned by "Toro" and Ryan no longer makes rotary mowers of this type.  Ryan Turf Care was recently sold from Textron to Commercial Grounds Care, Incorporated.  The Ryan name may have changed a few hands, but the basic business is still lawn/turf care. 

Thus far, I've been tracking down vintage Lawn-Boy wheels and a discharge chute for the deck.  It hasn't been easy since the mower was manufactured around 1980.  The B&S engine's date code reflects 27 October 1980.  Ryan made this particular mower from 1978 to 1984 - take a pick at the year of my mower.  Overall, it's been a fun project.  I have decided to preserve the mower instead of restoring it.  There is a major difference and the problem would be trying to replicate the paint and decals.  I plan to show it during the various 'vintage days' that would allow an older rotary mower to be present.  Collecting older mowers has been a fun project, but I can tell you that you won't make any serious money in doing so.

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