Small Engines (Lawn Mowers, etc.)/1971 B & S engine


Hey there! I'm helping out a father of a friend who has some small projects dealing with engines and such.

He has this old Briggs and Stratton engine that we are trying to get running. I think it's a 1971 tiller engine, but i can't find out. Model F30902, Type 0178 02, Code 7103177. I've got some mechanical experience, studied Honda, Yamaha and BMW motorcycles, but its been a while since I've worked on anything.

It has no spark and I believe its from the ignition system being shot. Lots of the wires behind the ignition coil have broken jackets and such.

I was wondering if its possible to swap out the ignition coil and magnets from another small engine and put it on this one and if there is any way of getting a repair manual for the engine.

Just use a 1981 or new igntion module that will bolt to the engine.  All 81 and newer Briggs are electronic ignition moduels.  No need to swap the flywheel magnets.

Manuals are availbe all over the place...internet, Ebay, maybe even your local library.

Should only be about 3 wires running behind the flywheel.  One from the coil to the points and another one for the engine shut-off.  Seems I remember 3 wires on a couple of modules but can't think of what the third wire was for...must not have been that important.

FYI, tiller enignes are the hardest to get running if they were used a lot.  Dust and dirt eat the cylinder, piston, rings, valves, valve guides, carb butterfly shafts and the like.  I have spent many hours trying to get some old tillers running tip-top but have had few sucess unless there was a complete overhaul, bore, valve guides, rod and a brand new carb.  Can be very expensive these days.


Small Engines (Lawn Mowers, etc.)

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Eric A. Jones


Lawnmower Repair . Certified Master Service Technician from B&S. Have 23 years experience on B&S, Lawn Chief, Weed Eater, Echo, Peerless, Wheel Horse, Snapper, Atlas, MTD, McCulloch, Homelite and many other numerous brands. Specialize in electrical repair.


Born and raised in the midwest. Started tinkering with engines when I was about 14 on my Suzuki RM-80. I began lawn mower repair at a small hardware store. I knew absolutely nothing. I read lots of repair manuals and met an older fellow who taught me many lessons. I continued working on small engines through high school and paid my way through college working on mowers at the same hardware store. Decided to get away from the midwest and mower repair so I joined the Air Force. I repaired air traffic control electronic equipment and ended up in Hawaii where I got a part time job at Small Engine Clinic. I gained a lot of experience from the Small Engine Clinic and had a blast repairing small engines. I then took the Briggs and Stratton Master Service Technician test and earned my MST. I then traveled to Wisconsin where I attended the factory update training seminar and received formal training. Continued working on mowers part time as I completed 20 years of military. Retired from the military on a Friday and continued in the lawn and garden industry the next Monday.

MAS Aerospace Operations BA Mathematics AAS Electronic Communications AAS Electronic Technology

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