B&S. Replaced primerbulb & tried 1 then 2 gaskets. Still won't prime.

[Rob-Bob]

Briggs & Stratton Mo. no. 123K02 0336 E1 050627 FA (6.5hp)

Toro Mower runs fine and cuts grass with single pull by squirting a few drops of gas into carb with air filter off. So what I have read so far is replace primer bulb, install one or two new gaskets (I tried both ways) still no priming action. I was able to get gas to come out primer tube by putting a dropper against priming orifice and squeezing air through it.
Then I read air cleaner plate could be warped, so try 2 or more gaskets. I have carefully examined the air filter back plate and can't detect warpage for sure. How do you acurately check it?
Then I read use some gasket maker or gasket sealer. How much? What type or brand works best?

 

[motoman]

Check warpage: Poor man's surface plate. A piece of glass or the cast iron machined portion of a table saw/. Absolutely clean! Place suspect warp surface down and attempt to slide feeler gauges between the flange and surface plate. Should not be over about .010" air gap. Attempting to crush several gaskets into a warpage mostly does not work IMO. If the thing is warped bad you can feel the problem by rocking it or looking for a "light band."

 

[Rivets]

Have you checked the float level in the carb. If the float is not set properly, the primer may not be able to push the fuel all the way up the nozzle.

 

[Rob-Bob]

Check warpage: Poor man's surface plate. A piece of glass or the cast iron machined portion of a table saw/. Absolutely clean! Place suspect warp surface down and attempt to slide feeler gauges between the flange and surface plate. Should not be over about .010" air gap. Attempting to crush several gaskets into a warpage mostly does not work IMO. If the thing is warped bad you can feel the problem by rocking it or looking for a "light band."

Clever idea for checking warpage. Why didn't I think of that? I'll check that. Thanks motorman for your reply.

 

[Rob-Bob]

Have you checked the float level in the carb. If the float is not set properly, the primer may not be able to push the fuel all the way up the nozzle.

Would the engine run properly (it runs well enough to mow) if the float level is not correct? I am reluctant to remove the float bowl, at this point, when the o-ring/gasket has a 50/50 chance of breaking.

Thank you Rivets for your reply.