On 2/4/2010 5:48 AM, Mike Eldred wrote: > My question to listers is, has any one else ever encountered this clear > lamination, and is it necessary to the proper and lasting function of the > diaphragm and the pump? > The pump from my '69 had that clear lamination. I'm thinking that it helps the neoprene diaphragm last longer. Cheers, Dave Ambrose