I have a toro 21 super recycler, 1 year or so old. It has a B&S engine. There is a tube that runs from the engine to the air intake just below the filter that seems to recycle engine gasses. I notice that when the tube is connected the engine slows down. When I remove the tube the engine speeds up and runs better. My tube also seems to spew a decent amount of blue smoke and there is some oil. Surely this is not the intended design. Can anyone shed some light on what should be happening here? Surely there shouldn't be oil going into my carb with these return gases? I am running it disconnected for the time being. Mower runs better like this. My son uses this mower to mow multiple lawns a week. Also - who put that overflow on the gas tank that spills into the air filter housing. That is dumb. thanks in advance.
Toro/B&S engine question
- Thread starter thurmjw
- Start date
The tank ”overflow tube” is not an overflow tube, but a method to capture fuel vapors ob burned off, as well as a tank vent to prevent the tank from vapor locking. Government regulations. Please post the mowers model and serial numbers, I think I know the problem, but don’t want to make guesses until I know which engine you have.
The first thing I would like you to check is the oil level. Also smell the oil, I’m thinking that you will smell gas in the oil and it will be over the full mark. If that is the case the float needle is not seating properly, allowing fuel to drain straight through the carb into the crankcase. If that is not the case, start the engine and with it running slow remove the dip stick and let it rest on top of the fill tube. It should not bounce around. It if does I suspect a blown head gasket. Post back with what you find. Please include the date of purchase and the mowers model and serial numbers.
oil was low. It is definitely blasting oil out the exhaust gas recycle tube that connects to the air intake for the carb. When I leave it disconnected there is considerable oil build up on the mower where it blows out of the tube. Oil does not smell like gas. When I undo the oil cap there is significant oil blowout, smoke and the cap bounces around because of this. The thing runs pretty well other than that. You can definitely cut a lawn with it. It was purchased second hand over a year ago.
mower model 21387
serial 406718561
mower model 21387
serial 406718561
Watched an online video so I am an expert now on disassembly
. I am taking it apart. I am no mechanic, but I am pretty sure that taking off what I think is the valve cover shouldn't spill out a bunch of oil right? It is filled with oil. There are two little rockers in there. I am removing it to get to cylinder head. Still think we had a blown head gasket? And this is allowing oil to go places it shouldn't?
. I am taking it apart. I am no mechanic, but I am pretty sure that taking off what I think is the valve cover shouldn't spill out a bunch of oil right? It is filled with oil. There are two little rockers in there. I am removing it to get to cylinder head. Still think we had a blown head gasket? And this is allowing oil to go places it shouldn't?I believe you. I dug all the way in, the gasket came off in pieces and there was plenty of crust on the cylinder head and valves, etc. like maybe there was some oil cooking in the cylinder along with our gas. I guess clean it up, I have some parts cleaner, buy a new gasket and see if I can put it back together? Is there anything else I should check while I have all this apart? There is an ace hardware that deals mower parts near me. I hope they have it.