Small Engines (Lawn Mowers, etc.)/Small engine choke


QUESTION: I have a 6.5 HP replacement mot or from Harbor Freight on a rototiller. Unable to start,no fuel in fuel bowl Took off fuel bowl, manually worked the float and needle valve to regain fuel flow. Replaced the bowl. Engine runs but only with full choke at above idle. At idle it will run with choke off.

 Thanx   Jim

ANSWER: There are 2 circuits in most carburetors, one for idle (low speed) and one for running (high speed).  I would start by removing, dis-assembling and cleaning the carb as it sounds like the high speed circuit it not working.  Probably one of the carb passages is dirty.

You will need an air compressor and some spray can carb cleaner to clean the carb.  Blow compressed air through all the carb orifices and follow that with come spray can carb and verify you can see carb cleaner travelling through the carb orifices...wear safety glasses.  Finish with compressed air again and then re-assemble and re-install.

Let me know if cleaning the carb fixes the problem.

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


  Thanx for the response. I probably won't get to it for a few days and will let you know.
   Does the placement of the bowl make a difference?, as there is a couple of indentations on the bottom.


Sometimes some float bowls do need to go on a certain direction but I have messed this up in the past and it did not make a noticeable difference in engine performance.  Many Tecumseh carbs have a detent in the fuel bowl...the detent is supposed to be positioned directly under the inlet needle.  I'm not sure on the HF engine as we do not see many come in the shop...costs more money to repair them than to just buy a new HF engine.

I don't think the HF carbs matter, they are similar to old Honda carbs, but it might be a good idea to take a trip to your nearest HF store and check out an engine to see which way the bowl goes on.

I still think there is a fuel issue, dirty carb or maybe an air leak.  Did you try cleaning the carb with compressed air from an air compressor?


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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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