HAVE HAD THREE MAXTRA PUMPS SENT TO ME FROM -DIRECT POWER AU- WITH "HONDA COPY" MOTORS, ON ALL OF THEM, THE BREATHER PASSAGE FROM THE TAPPET COVER TO THE AIR FILTER WAS BLOCKED, THE PASSAGE WAY WAS NOT MOULDED PROPERLY IN THE PLASTIC HOUSING AND IF LEFT AS IS, WILL CAUSE THE MOTOR TO BLOW QUITE A BIT OF SMOKE AND CONSUME EXCESS AMOUNTS OF ENGINE OIL, AND WITH NO LOW OIL PROTECTION ON THE MOTOR THIS COULD HAVE DISASTERUOS CONSEQUENCES SUCH AS A DESTROYED MOTOR DUE TO RUNNING WITH LOW OIL.
TO CHECK IF YOU HAVE THIS FAULT SIMPLY PULL THE BREATHER HOSE OUT OF THE TAPPET COVER AND SEE IF YOU CAN BLOW THROUGH IT INTO THE CARBURETTOR HOUSING, IF YOU CANT THEN YOU HAVE TO DRILL OUT THE ORAFACE INTO THE PLASTIC HOUSING.
THE CURE FOR THE PROBLEM IS TO UNBOLT THE MOTOR FROM THE FRAME, THEN REMOVE THE AIR FILTER PLASTIC BODY AND RUN A QUATER INCH OR 5 SIXTEENTH INCH DRILL THROUGH THE BREATHER ORAFACE IN THE PLASTIC HOUSING, YOU WILL FEEL IT WHEN THE DRILL PASSES THROUGH THE PLASTIC OBSTRUCTION. STOP IMMEDISTLY WHEN YOU FEEL THE DRILL PASS THROUGH OR YOU WILL DO UNWANTED DAMAGE TO THE HOUSING. TEST IT IS CLEAR BY BLOWING THROUGH IT AND TO CLEAR OUT ANY PLASTIC SWARF. REASSEMBLE AND THE PROBLEM IS CURED
ADD-ON------ instead of removing the plastic housing and drilling the blockage, take a piece of quater inch steel rod and sharpen it to a longish tapering point then bend it at right angles about 2 inches from the point, then remove the rubber pipe from the plastic housing whilst it is still attached to the carburettor and force the pointed end in the oraface untill you feel it pass through the thin plastic blockage and come against the opposite wall, wriggle it around a few time and presto, you have cleared the blockage. quater inch steel rod is sufficent as it doesn't need a really big oraface for the engine blow-by gasses to pass through into the carburettor and be recycled and burnt.
Try to pierce the plastic blockage several times and wriggle the steel rod around as much as possible to try and damage and break up the blockage, as the plastic has a memory and will try to go back to it's original shape and will reblock the hole. I tried to blow through one I had perviously pierced with the steel rod and I could hardly blow through it, the problem had recurred. If it is not too much of a problem I suggest removing the plastic housing and drilling it out for a much more positive result.