Hello all,
I'm new to the site & am looking for help. I recycle used mowers & string trimmers for anyone needy & sometimes sell too. I have a B&S 6.0 hp that won't run with an air filter installed. The numbers are: 11A602 0125 E1 001012 FA. It is an overhead valve engine. So far I've tried: Rebuilt carb., set the valves, replaced main jet, reset governor, reset air gap. The plug is dry & black. I also pulled the head & scraped the carbon off the piston top & cleaned the valves.
This would suggest a rich condition but there are no adjustment screws on the carb at all. This engine starts fine but sputters when the air filter element is out. Put it in & it dies. It was doing this when I got it, so I haven't hurt anything, but I haven't fixed it either.
Mower personnel told me if the main jet didn't fix it, to bring it in. That kind of defeats the purpose. I don't want to spend a fortune on it to give away. I would appreciate any input you could give me. Thanks in advance.

pumper

Check for an air leak between the carb & engine block... a slight restriction, (with filter), could be enough to lean it completely out.. KennyV

KennyV,
After rebuilding the carb, all gaskets were replaced with new. I saw no indication of gouges, chips, etc. on the surfaces. Would spray on carb cleaner show a leak? Thanks, pumper.

Originally Posted by pumper

KennyV,
After rebuilding the carb, all gaskets were replaced with new. I saw no indication of gouges, chips, etc. on the surfaces. Would spray on carb cleaner show a leak? Thanks, pumper.

Yes if it pull it in...
it will richen up the fuel mix, you will hear it... KennyV

Hey there! WELCOME to LawnMowerForum!

I moved your thread to the Small Engine & Mower Repair Forum. You'll get a better response there.

Hi,
Well, I sprayed carb cleaner around the intake gasket & had no change. I removed the air filter backing (which connects to the breather assy.) & it ran fine. A little too fast I think. Blocked the carb throat completely with air filter & nary a flutter. Put it all back together, it died.
I've cleaned the air breather assy. out, so is it possible to have a timing or governor issue? Gettin' close to trash day! Thanks, pumper.

You said you rebuilt the carb but the seal in between the carb and the back of the air cleaner box could have sprung a leak. I have seen this happen many times with engines like this. If it is not perfect then it could make it quit. Did you try to put the box together without the filter in it and see what Happens?

jteuban May be on the right track... put it together without the filter element, like he suggested...
There may be a kill switch incorporated with the throttle linkage that some how is getting shorted out when you assemble everything... Look for a wire and see that it is not shorting out the coil... KennyV

The thing that sticks out for me is the plug read. Black means rich. So I might ask how did you clean the carb? Could you have used something in the main jet that made the hole larger?