1998 Kawasaki 65Z 4 air leak

I can hear air pissing out under the ladder/stairs on the 'driver's side'. There look to be 2 housings there that look like they could be diaphrams. The air gauge held the middle of the scale. Any ideas on what could be amiss? Is it going to be a big problem? Would it likely to be expensive to fix? Machine at auction tomorrow. TIA