OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines ROVER 375 MISFIRE

Hi,
Im trying to fix my neighbour's Rover 375 Briggs and stratton mower.
The mower misfires and the revs dont go high too much.
If i manipulate the carby by finger it revs and revs high.
The springs look ok .
I have cleaned the carby and changed the diaphram spring and gaskets. Also have cleaned the flywheel , coil and set the gap at .20mm . I have a manual says between .15 - .25mm. No change.
Changed the spark plug to new and set the gap to .75mm.
The only thing that concerns me is that there is rust building up on the flywheel magnet face. The mower has excellent spark and great compression. Muffler is not plugged up and have decarbonised the piston and exhaust areas. I have changed the oil and fitted a new air filter.
Im stumped!! please help

Thanks

dristo72,

Not a hard one to fix. All you need to do is where the spring is connected you will have to bend the lug as he has most probably pushed the mower under a shrub and bent the lug back reducing the tension.
This tensions the spring for the gov and also speed.

From your description this has nothing to do with your problem - since the engine will rev when you flip the throttle valve directly it is clearly a governor problem as Bruce said. However the B & S specifications as I read them say the breaker gap needs to be 0.020" (0.50 millimetres). Unless there is something unusual about this particular model, you may have used the wrong information here.

Hi Bruce, the mower has 2 springs
both connected through the thick wire eyelet wire that connects the govenor arm to the throttle valve arm and attached to the plate that shorts out the earth wire. do i bend the plate on the side with the short out wire or the actual wire with the eylet?
Thanks

The one that has the larger hole (longer spring) in it is the one that will increase the high speed rev's the other one is the idle speed.

Hi Bruce,

Thanks your a legend, all fixed.

Cheers

Glad to see you got it all sorted out.