Tecumseh 17 1/2 HP Engine

Gentlemen, I recently purchased a Murray Riding Lawn Mower, automatic drive, with a 17 1/2 HP tecumseh engine. My problem is that from day one, when starting the motor the governor oscillates back and forth causing the engine speed to slow down and speed back up. The carborater cable is adjusted according to the manufacturer's instructions. If I move the speed to the slow position the engine settles down and after three or four minutes I can move the cable to the run position and the motor runs fine. Does anyone have any idea what to do about this problem. It is a pain in the rear to have to wait for the engine to warm up this long prior to use. Thank for any help. P.S. I work all the time and I haven't had a chance to call the manufacturer or take it in for service. I've only had it about three weeks.

 

Hello cmsgtsmith

3 or 4 minutes isn't all that long of a time for an air cooled engine to warm up some, prior to putting any load on it. It allows for some normal internal engine parts to expand and the oil to thin some.

The most likely cause for this problem is the automatic choke, if equipped with one. If there are puffs of black smoke [light or dark colored} exhausting from the muffler, the choke may be too tight. If the choke is too loose, the fuel mixture will be too lean. Either of these can cause the engine problem.

Also read the owners manual regarding warmup times and choke settings. Also any intructions on carb settings. However, be careful not to run the engine too lean if it currently runs well once warmed up.

Adjusting the carb to cure the cold running problem so there wouldn't be any 3-4 minute warmup waitting time can cause severe warm engine running problems.

Regards and Good Luck,
Tom_Bartco
Accurate Power Equipment Company.
Small Engine Service and Repair Technician.
Personal Quote:
"If it ain't broke, don't fix it until it is broken!"
Bare in mind my company no longer services nor repairs lawn and garden powered equipment. Rest assured and fully confident, the help I offer you is based upon my prior years in this industry, with this type of equipment and is specific and accurate to the best of my knowledge...

 

Recently, Techumseh has started making poor quality carburetors. It sounds like your engine may be running too lean. The carburetor you have may not have an air/fuel adjustment screw, as most newer techumsehs do not. I dont want to disappoint you, but if you can, I would reccomend returning your mower, and purchase one with a Briggs & Stratton engine. Techumseh has quite a few problems with their new engines. I own a small engine repair service, so I see a lot of them. If you keep it, make extra precautions to keep it FULL of clean oil, and let no water get in the gas.