Walbro 75-570-1 float (I'm 95% sure) - much cheaper (From Power Distributors) and I'm fairly sure replaces 398187 float - May be worth a bit of homework to cross reference Walbro with Briggs & Kohler carb parts , often much cheaper from Walbro. I think they're just a buck or two each, cheaper than the time spent heating and adjusting float levels, no?KE4AVB wrote:Now about the float level I have seen some where the level when install is low even with new parts. I have been heating the plastic float hinge to get them level.
38racing wrote:I'm stumped. The engine is a 12h802 and the carb came from a 12h802. I put carb back through USC then sprayed all passages repeatedly with carb cleaner and compressed air. Still had to continually prime for2 minutes before it would stay running. At that point putting finger over primer bulb hole would cause to falter to point of stopping. When rpm drops with falter the governor opens the throttle but it continues to stop. After 5 minutes of running then putting finger over primer bulb hole causes a slight drop in rpm but it stays running. I'm using original o ring on the intake pipe. Can't think of anything else except checking intake valve clearance. I do have another similar mower just left at dumpster. I guess I could see if I can get it to run and then try it's carb on the problem engine.
bgsengine wrote:Walbro 75-570-1 float (I'm 95% sure) - much cheaper (From Power Distributors) and I'm fairly sure replaces 398187 float - May be worth a bit of homework to cross reference Walbro with Briggs & Kohler carb parts , often much cheaper from Walbro. I think they're just a buck or two each, cheaper than the time spent heating and adjusting float levels, no?KE4AVB wrote:Now about the float level I have seen some where the level when install is low even with new parts. I have been heating the plastic float hinge to get them level.
I suspect you are thinking of the pulsa-prime? All the float carb primers on that type L-Head should be vented, as all they do is inject air into the float bowl to push fuel put the main nozzle, they need to suck in air to the bulb to recharge., Its the pulsa prime that sucks fuel from metering well to push through and inject fuel into carb throat, so they'd have closed system.. If blocking off the vent on the primer changes how the engine runs, I'd be thinking a problem with air bleeds or cracks in carb allowing too much air (or float level or corrosion in a metering passage restricting fuel flow or fuel level)KE4AVB wrote: The covering of the primer hole shouldn't cause a problem as most primers used with this carburetor are closed system but the image of the primer does appears to be a vented bulb.
bgsengine wrote:I suspect you are thinking of the pulsa-prime? All the float carb primers on that type L-Head should be vented, as all they do is inject air into the float bowl to push fuel put the main nozzle, they need to suck in air to the bulb to recharge., Its the pulsa prime that sucks fuel from metering well to push through and inject fuel into carb throat, so they'd have closed system.. If blocking off the vent on the primer changes how the engine runs, I'd be thinking a problem with air bleeds or cracks in carb allowing too much air (or float level or corrosion in a metering passage restricting fuel flow or fuel level)KE4AVB wrote: The covering of the primer hole shouldn't cause a problem as most primers used with this carburetor are closed system but the image of the primer does appears to be a vented bulb.
bgsengine wrote:38racing wrote:I'm stumped. The engine is a 12h802 and the carb came from a 12h802. I put carb back through USC then sprayed all passages repeatedly with carb cleaner and compressed air. Still had to continually prime for2 minutes before it would stay running. At that point putting finger over primer bulb hole would cause to falter to point of stopping. When rpm drops with falter the governor opens the throttle but it continues to stop. After 5 minutes of running then putting finger over primer bulb hole causes a slight drop in rpm but it stays running. I'm using original o ring on the intake pipe. Can't think of anything else except checking intake valve clearance. I do have another similar mower just left at dumpster. I guess I could see if I can get it to run and then try it's carb on the problem engine.
when carb is apart do you happen to notice if the float sits level? or a bit "up" from level? (low) . If it is "up" from level, then you got a swollen float needle seat and fuel level is too low in carb bowl. (Bowl needs specific level of fuel to reach the fixed jets properly)
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