Small Engines (Lawn Mowers, etc.)/Honda GX620 motor


QUESTION: Hi Eric, I have a Carryall 294 4x4 with a Honda GX620 motor GCAD-2134319. It sat for about 2 years before I got it, I drained the gas tank the best I could with out removing it. replaced all the fluids and filters, spark plugs. I replaced the carburetor because I saw that they cut the solenoid wire, and the dealer wanted 103.95 for the solenoid, the carb was half the amount. It stared up great ran good for about 15-20 minutes, then it felt like it wasn't getting enough gas but it also smelt a little rich then it started backfiring though the exhaust. Tonight I replaced the the new gas filter because the new one had some stuff in it. It started but it wasn't idling smooth and when I took for a test ride, it started good then felt like it was starving for fuel and popping through the exhaust again.
Thanks for your help.

ANSWER: How old is the fuel you are using?  Less than 30 days old?

Were there any plastic insulators, gaskets, or o-rings between the carburetor and engine?  

Have you checked the valve clearances?

Let me know.


---------- FOLLOW-UP ----------

The gas is fresh 100% gas not ethanol blend, there is a spacer and 2 gaskets between the carb and the engine. No I haven't checked the valve clearances. The other thing I noticed is when it starts running really rough it doesn't want to engage the clutch to go forward you have to put it in reverse then back into forward to go, but that only happens when it sounds like its running out of gas.

I would check those gaskets and the spacer.  If the space is plastic I have seen these warp and leak when the engine warms up.  Do you have a little Permatex II non-hardening to help seal the gaskets?  It only takes a LITTLE bit...DO NOT use too much.  I have used Permatex II non-hardening to help seal warped spacers.  It is messy stuff...USE rubber gloves and DO NOT get any on your clothes.

Do you have feeler gauges to check the valve clearances?


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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