Outdoor Power Equipment and Small Engines - Tecumseh Mower

I'm having problems with this mower. It is running erratic. It starts on the first pull, does not surge. Things I have done to it: I have taken the carburator off twice, cleaned with ultra sonic cleaner and carburator spray. I've replaced the needle and seat and the two O rings in the main nozzle. Checked float, no gas in float. Valve clearance is between .004-.010. Checked combustion chamber, no carbon build up. Replaced head gasket. Also I did a leak down test, replaced coil, with no effect. It still runs erratic. I have not replaced the fly wheel key. Model number is 143.993512 (Tec. LEV100).

Need help.

Thanks,
Jerry:wall:

I'm assuming you've changed the spark plug? Erratic running.... can you elaborate?

Also check the gas for water. I found lots of mowers with water in the gas last summer. If you are in an area that uses E-10 (10% ethanol) then you most likely have water in the gas as ethanol will actually attrack water. This is very common in my area that has used E-10 since Jan. 08. E-10 also has less power.

I think if you will clean the tiny hole at the top of the bowl nut(main jet) it will run much better, I usually use the wire from a twist tie, refer to the link below. Have a good one. Geo
http://i190.photobucket.com/albums/z120/geogrubb/tec_bowl_nut.jpg

I have replaced the plug twice,has fresh gas,and also clean the tiny holes in the main jet all three.Cheese is there a tiny hole in the threads just below the main nozzle where the main jet screws in ,or this another carb.I also took out the idle recitor screw on the side of the carb. and clean the tiny holes in it.still runs erratic.

Jerry

There should be 4 holes in the bolt that holds the bowl on. The tiny one near the end is usually what gives trouble and can be hard to find it if it's clogged.

I still don't know what you mean by running erratic. Revving, skipping, laboring, cutting on and off, or...????

Cheese,I found all the holes that holds the bowl on.The hole that goes all the way through the bolt I count it as one.Anyway I guess you could say it is running rough all the time pops every now and then through te exhaust.It has good power,runs at 3000 rpm.Compression gauge shows 85#.Still starts on the first or second pull.

Jerry

I'd say have a look at the flywheel key. If it is in perfect condition, then I'd say you either have a problem with the exhaust valve or still in the carburetor. I suspect the flywheel key is slightly sheared, or "pushed". Pull it out and see.

Thanks,Cheese I will check the flywheel key,and get back with you

Jerry

Update,check the flywheel key,found that it was slightly sheared.Replaced the key, and now it run great.Thanks to all,this is a great forum.

Jerry

Great! Glad we could help! Thanks for the update.