Hello

I own a rover mower with briggs and starton motor and it wouldn't start so I put a new spark plug in and clean the air filter with new fuel and I started it and it idle rough so I put my finger over the fuel primer bulb breather hole and it ran perfrect so I took my finger off and ran rough.

Would I need a carby kit or just new primer bulb?

To me it sounds like air/furl misture is not right, but I'm no expert on mowers

Can anyone help me with my problem?

Before you do a carb kit sounds like you are losing suction on the fuel line. Check fuel filter first and the clamps on that line. If sounds clogged and the fuel pump is losing prime until you put the finger over the prime bulb.

Do these little mower have fuel filters ? It's a briggs and stratton auantum 120000 I thought they feed striaght off the carby with no filter.

Primer bulbs don't have holes in them. Replace it.

If they didn't have holes are would they pop out again?

Parts & Supplies - Briggs & Stratton (http://www.briggsandstratton.com/maint_repair/parts_supplies/details.aspx?pid=694395)

That's not what I'm used to seeing.

The air usually pushes up on the diaphram of the carb, so you might have a hole in the diaphram.

O OK so how do I know if the diaphram is broken?

I lent it to a friend and he was an idiot and while it was running he kept pushing primer buttom to FLOOD IT!

Ever since then it doesn't run good so I replaced spark plugs and air filters and fuel and ran rough so I put my finger over primer button hole and it ran perfect.

Spark plug*

Based on your additional info, I really think the diaphram is shot. Rebuild kits are typically <$15. You might be able to get away with just replacing the diaphram, but the carb has to come off, because the diaphram has to be facing UP when you remove it to avoid losing the valve.

If you only replace the diaphram then you wouldn't have to worry about setting the mixture from scratch.

Now it won't start I've have tried almost everything I can think of, first I flushed the fuel tank and put new fuel in still didn't start then I cleaned the coil for surface and set the gap again and cleaned the flywheel/magneto from surface rust still didn't start then I cleaned out carby and bowl and bowl screw with carby cleaner and cmpressed air in all the holes still didn't start then I took out the valves and cleaned all the seats and the valves and the top of the piston and any other excesse carbon there was a lot of carbon still didn't start then I put new spark plug and air filters in still didn't start I also tried starter fluid and still didn't not spark. Lol the only thing I can think of now is piston ring? I can't think of anything else . Can anyone help me!? Lol