by bgsengine » Sat Mar 09, 2024 4:45 pm
1) Probably won't need to pop out the primer bulb itself just yet - Most often the reason for no prime is a warped tank or carburetor body
2) diaphragm to tank side, gasket goes carb side (easy to put them wrong)
3) If you put a new diaphragm and gasket kit on it (and those aftermarket ones you can get on amazon are same as the Stens ones, they all work quite well usually) make sure and save your OLD gasket if you can keep from damaging it
4) Check tank for flatness - straightedge across it and if you can fit a .002 feeler gauge under straight edge at any point, tank is warped
5) Very very common to have those nylon body carbs come in with the screws having been over-tightened (and not torqued in a pattern) which causes the nylon carburetor body to warp (and eventually the tank surface follows)
6) DO NOT overtighten the screws - start with the screw closest to carb body and go counter-clockwise around, just fingertips ion screwdriver to snug them in a circular pattern, then go back over them with just a bit more torque (but not ham-fisted crank-down tight!) fingertip tight is enough
7) after putting new diaphragm and gasket in place and it still won't prime, pop carb off and inspect gasket for impression of the sealing bead that is molded into carb body and you'll probably visually see where it is not fully seating (indicating carb or tank or both are warped) Minor warp can sometimes be resolved by doubling up on the gasket (Some D&G kits come with 2 gaskets for that reason!) if doubling up gaskets, add just a tad more torque to the screws to help further compress the gasket material . Severe warp can sometimes be corrected by finding the point at middle of carb gasket that isn't seating fully and cutting a piece of old gasket in that area to "thicken up" and use a razor or Xacto knife to feather the edges thinner to smooth out the connection between gasket material thicknesses.
In my many years working with those carburetors, I have only ever ONCE had to replace the check valve (and it's a pain in the ass to do anyways) because the steel ball rusted and spring broke. (it sat through a flood and then sat in the weeds for a couple years) Don't really need the pliers to pop out the bulb if you have replacement bulb and retainer (The better aftermarket ones come with new retainer) - just pop em out with screwdriver one side at a time (bit by bit on each side) - MUCH more handy if you are gonna buy a tool for them, is the primer bulb INSTALLER (too easy to stab a hole in bulb when trying to seat thing swith a screwdriver)
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)