Hi folks,

I've looked through the site but can't find an exact answer to my problem.

I have a "b&s powerbuilt 12.5 hp" on a ride-on tractor mower, but don't know the model number.

The engine cowl has "5bsxs.3442vm 276012" stamped on it, but this doesn't seem to match anything on the b&s website.

I'd like to get my hands on a technical manual if I can find one on the web.

My problem is that the engine has started blowing white smoke when the throttle is open and it looses power and stalls. It idles fibe without smoke.

I changed the oil, rechecked the oil levels to make sure it wasn't over full, cleaned the airfilter, changed the fuel filter (maybe the fuel flow isn't right through the new filter? )

Any help much appreciated !

Thanks,
Martin (Garranmore), Ireland

What about the breather assembly, do you have oil going into the carb through the air filter housing?

Thanks for the quick response. I think that oil is going through the breather, how can I confirm this? If it is, can I fix it ?

Regards,
Martin.

To confirm it, remove the air cleaner housing top, and the air filter. See if there is any oil on the filter, or on the filter housing. If it is the breather, you can easily replace it.

After rechecking, I found that oil was not going through the breather, but it would appear that my Oil was contaminated with fuel. I changed the oil again.

Engine still wasn't running right and kept flooding, so the problem looks like the Carb. The gasket on the float chamber is shot, but I can't find my engine serial number. The engine is a 210000 series. I've fiitted an old carb from another B&S engine and the engine runs much better, but I want to put the proper Carb back once I've managed to get it serviced.

Any ideas where my engine serial number will be, as its not on the fly-wheel housing.

Thanks.