Hello I've found that this forum is the best place to go for advice on any small engine. So I'm back again.

ok here goes. I have a 10a900 2085 B&S engine on a Bolens mower. The engine runs great after I pour some gas in the carb and get it going. But the primer will not get any fuel in it to prime the engine. The primer will prime after I have had the engine running.

Any suggestions would help. This isn't too big of a problem but it does make it so I am the only one in the house that will mow the lawn. My wife actually enjoys doing the lawn from time to time but doesn't want to pour gas in the carb.

if its the type of carb that screws on the gas tank and has the airfilter above the primer/carb ect , then you probally need to just replace the gasket for it , theres 2 parts to it , the diaphragm and the rubber part , if you unblot the gas stank and take the carb off you can change that gasket , then you should be set , i've had a few briggs sprint motors do this and the reason why is the rubber gasket isn't sealing off the port on the carb so it will suck gas up , i bet if you try tipping the mower up like you are lifting the back of the mower up off the ground and try priming it it will prime fine because your forcing the gas up in the carb

Yes it is the type that sits in a stack on the gas tank. I just replaced the diaphragm gasket three weeks ago and it primed and ran fine the first week then the priming issue came back.
I guess maybe something loosened up or I nicked the gasket. But If I did damage the diaphragm gasket wouldn't that cause other problems like running rough or stalling?

I might just have to spend those $5 again and do the diaphragm again and make sure everything is clean.

are there any spots on the carb that might be clogged preventing the siphon for the primer?

Is the primer mounted on the filter body with a gasket between the filter body and carb?

I'd take the carb off and blow it out with compressed air through all the little holes good, the diapragm should not cost more then 2 or 3 bucks. You didn't fold the gasket or diapragm did you?

be careful where you blow air or you will pop the primer bulb might want to check the o ring make sure its set in the groove

OK I'll rebuild it again and blow air through it to make sure everything is nice and clear. Nope I didn't fold or crease anything. Should I have to clean off the top edge of the carb where the diaphragm goes to make sure it is smooth. My thinking here is that maybe it has a slight defect and is leaking some air. Yeah Bugman, it is only about $2.75 for that rebuild kit at the local shop.

I figured out the problem it was so easy it was staring me in the face...
everytime I looked in the mirror.
Yep I'm an idiot j/k I decided to pull the carb apart and see what damage i did to the diaphragm that caused the problem, well after taking it apart I looked at the two gaskets and realized I had put them on in the wrong order when I rebuilt it last and this caused the diaphragms flap that seals the primer bulb too far away to create a seal so no suction.I guess the first place all of us should look when trouble shooting is the operator. I'm going to go beat my head against the wall now... Well after I mow the lawn.