My briggs and stratton Model 12H802 engine is hard starting

Most of the time, when the problem is NOT the primer bulb, then it IS the gasket behind it. Sometimes, an easy way to see if there is a blockage (at least on the primer bulbs that have a little hole in the center) is to stick a tiny red tube directly into it and give it a shot with carb cleaner.
I hope this helps!

It is used to bring fuel to the carb before starting. Push it in 5 or 6 times before attempting to start.

I WOULD GO THRU THE CARB, CLEANING, AND REPLACE NEEDLE, SEAT, FLOAT, AND ANY GASKETS. A REBUILD KIT FOR MOST BRIGGS AND STRATTON RUNS $10 TO $20 DOLLARS.
** USE A LOT OF SPRAY CARB CLEANER ON ORIFICES AND JETS

I am pretty sure this is a 4.5 Hp engine with the carb on top of the tank. Plastic carb 4 or 5 mounting screws mating carb to tank. Remove the air cleaner... and tighten the carb to fuel tank mating screws. It is drawing air between the tank and the carb. This should stop the surging. If is has been a long period that you used the mower with the surging problem the diaphragm between the tank and the carb may be either out of position or damaged. The diaphragm is not expensive. Usually the first time this symptom presents itself you can resolve it by tightening the carb to tank scresw. IF you have the primer bulb carb..mash the rubber of the bulb against the carb body. If the surging stops... the primber bulb has a pin hole in it.

You passed the mower model number and not the engine model number. When we use the 11A number you passed all we get is the base and handle parts. If you need more help I need the model number off the engine just above the spark plug wire on the air shroud.

Thanks for choosing Fixya,
Kelly

After a very extensive cross reference session your engine is model number
10H902-0285-E1 (not provided by you so it took a while)

Your engine is covered in this repair manual:
http://www.mymowerparts.com/pdf/Briggs_&_Stratton_Service_and_Repair_Manuals_Spec_Charts/270962%20Single%20Cylinder%20L-Head%20BRIGGS%20&%20STRATTON.pdf

If there is a problem that your having I can help you if you would just elaborate. I could save you lots of time. The 2 most common failures of this engine is on the carburetor. The parts that fail are the diaphragm (Item 394) and the primer bulb (Item 976) of this link:
http://www.partstree.com/parts/?lc=briggs_and_stratton&mn=10H902-0285-E1&dn=57160004

Carb data is in section 3 of the first link.
Thanks for choosing FixYa,
Kelly.

I really need your engine number but I am going to guess that it is a 3.5 to 4 HP Briggs & Stratton with a black primer bulb on the side of the carb.

Try this the next start. Take a screw driver handle just a bit smaller than the primer bulb and FORCE it against the carb body trying to make a seal with the primer rubber against the carb body. You use your thumb if you can manage to depress the entire area of the center of the primer bulb agains the carb body. If it runs normally when you do this..... the Primer Bulb has a pin hole in it. (No joy..... read on)

If after doing the above you strill have the same problem remove the air cleaner and tighten all of the screws that mount the carb to the gas tank. Often over time the carb body will warp and then it starts getting air introduced into the diaphram that is between the cab and the gas tank. Tighten the screws. There are usually 5 of them. (Remember the body is plastic.... tight but don't break it) Then try another start.

If that does not work the diaphram between the carb and gas tank is probably damaged and will need replaced.

If you need parts info respond with your engine number or go to www.briggsandstratton.com and look it up for yourself using your ENGINE TYPE MODEL SERIES number found on the air shroud above the spark plug.

Thanks for choosing FixYa.

Kelly

This Power washer has a 3.75 hp Briggs and Stratton Engine. It does not have a choke but does have a primer bulb. You must depress the primer bulb at least 3 times to start the engine. The primer bulb is on the side of the carb. It can be black or red. If your still unable to locate the primer bulb please provide your ENGINE model number and I will provide you a link to a diagram for the location of the primer bulb.

Thanks for using FixYa.

Kelly

I believe you have to remove the primer bulb and it is located behind it. Be careful and do not damage the keeper or the primer bulb there is a couple of notches on keeper to depress to remove,

find your local briggs and stratton dealer and purchase a new carb or primer bulb assy bot are pretty cheap

Your engine model # 128602 Type 0212-E1. Forget about ordering from Sears and paying shipping and waiting a week. Go to your local Briggs and Stratton dealer (most shops are) and buy part # 694395. Should cost about $3.00