Small Engines (Lawn Mowers, etc.)/homelite c5 fuel mixture


I have an homelite c5 s/n1434276. The fuel cap reads 1 pint sae30 to 1 gallon of fuel. Can I use synthetic oil? What ratio do you suggest?

WOW!  That's one old saw.

Based on the age I would not use synthetic oil.  I would try to find some Homelite mix oil and mix it 20:1 or 32:1.  Those old saws actually called for 16:1 but there are lots of articles on how the oil has improved over the years (decades) so you can run a leaner oil/fuel mix.  

It can be a personal preference as some articles say today's 50:1 oils are suitable but based on all the conjecture I prefer a richer oil mix as this will better lube the engine and help with cooling.  However, a rich mix produces more smoke, more carbon deposits and spark plug foul more often.   It's a trade-off but the richer oil will reduce metal engine wear.

It's up to you if you want to run a richer or leaner mix but I would stick to regular, not synthetic, oil mix.


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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