Working on an 031 AV that has the Walbro WA-2 carb with what seems to be a fuel delivery issue. Came to me with a new carb kit so that's the first thing I checked. All looked good until I checked the IPL to see if there was supposed to be a diaphragm under the circuit plate (doesn't appear to be). Turns out there is supposed to be a second diaphragm on the pump side though..., at least according to the WA exploded illustration in Stihl's 031 IPL. It's also shown in the Walbro IPL for a WA carb. D-10 and K-10WAT are the kits. Happened to have a couple of each on hand. Out of all the diaphragms included in the kits, only one pump diaphragm in either kit will fit the pegs on the cover. What appears to be the second diaphragm (surge/suction diaphragm) has a slightly different hole alignment as do the other pump diaphragms and simply will not line up with the cover pegs.
Guess what I'm wondering is if the WA-2 is exclusive to the 031 and doesn't actually use the second pump side diaphragm or whether there's a Stihl kit that includes it..., or maybe a different Walbro kit. Here's what's in the 031 IPL. #19 would be the diaphragm in question.
TIA for any enlightenment.
Guess what I'm wondering is if the WA-2 is exclusive to the 031 and doesn't actually use the second pump side diaphragm or whether there's a Stihl kit that includes it..., or maybe a different Walbro kit. Here's what's in the 031 IPL. #19 would be the diaphragm in question.
TIA for any enlightenment.