The diaphrams do go. My Yanmar was laid up with fuel in it for six years by
the PO and the diaphram in the electric fuel pump had disolved to about the
consistency of tar. It was just a sticky lump inside the pump. The fuel
had turned to jelly and I suspect it was the critters living in it rather
than the fuel itself that ate up the rubber.

Frogwatch wrote:
In a thread a couple weeks ago, I talked about failure of my fuel pump
on my 28' sailboat. It is a Yanmar 2gm that has a mechanical pump
that I backed up with an electric pump to make bleeding the system
easier. I am replacing the mechanical pump but I also need to replace
the electric one. The electric one was from JC Whitney and I do not
recall the brand. However, i do remember that it was not
specifically listed as being for diesel. It is a simple diaphragm
pump driven by a selenoid. I am wondering if the diesel could have
eaten away the diaphragm. Can anyone suggest a good electric fuel
pump fpr this application? JC whitney no longer has it available and
I do not trust it anyway. However, the original owner had it
installed when he bought the boat so I assume it was supposed to be
good. When it finally failed 4 years ago after nearly 16 years, I
simply bought an identical one. Any ideas?

--
-- Roger Long