Some
pumps can be easily rebuilt, others
cannot.
The design of the newer pumps makes it next to impossible
to get the old diaphram out. The only way you will know
for sure that yours CAN be easily rebuilt is to take the
upper pump body off of the lower pump body. If your pump
is still good and you are doing this in advance of the
pump failing you can do this without removing the pump if
you wish.
First
you want to clean the pump so you don't get any dirt
inside it. Then you remove the large ring of 6 screws
around the lower pump body. (Not the 4 screws that hold
the cap on). If you have a metal fuel line attached to
the pump you will have to remove it. Be sure to keep a
metal container handy as the line will drain. Do this
outside, never with a cigarette nearby and never with a
electric "drop cord."
To
separate the pump halves you may need to carefully wedge
a putty knife or kitchen knife around the circumference
to break the seal. (Are you sure you removed all 6
screws?) Once it pops up you can move it out of the way.
You will be looking at a big rubber disc with a shiny
plate in the middle. In the upper left of the above
picture you will see this disc (the diaphram) in this
picture it is upside down. See the peg coming out of it
with the"T" on the end?
To
remove your old diaphram you have to push the metal disc
down and turn the disc 90 degrees so this T will be
parallel to the slot that it is in, in the bottom of the
pump. I usually use the palm of my hand or both of my
thumbs to press down and turn. With just a little amount
of jiggling and experimentation you should have the
diaphram pop up. To reinstall it you simply line up the T
with the slot you see down below, put it in and push down
and turn 90 degrees and it will be "latched"
again.
If
no amount of pushing and turning 90 degrees every which
way will allow the diaphram to pop up you have a later
style pump which as of yet we haven't found a way to
dismantle easily. It can be done, but requires some
talent to press out the lower pin. With these you'll find
all kinds of positions, none of which will allow the
diaphram to pop up and be removed. One position will tend
to keep it pulled down in the body, you don't want this
if you are reassembling your pump for use, you'll need to
push down and turn it back so that it has that spring up
and spring down feeling when you push on it. But look on
the bright side, at least you didn't order a kit only to
find it would not help you...
Even
if you have the older style pump and decide to get a new
pump, I would suggest saving your old one, as there may
come a day when new pumps are not available and an
old-style rebuildable one will be nice to
have.
Do
you have some old pumps and are trying to figure out
quickly which are easily rebuildable? Check the arm that
goes inside the engine block, does it have a pronouced
rounded-off look? I haven't seen one of those that isn't
rebuildable. The newer style pumps have an arm that has
one bend and then is straight, is also longer then the
old style. Most of those I've seen have the pesky
diaphram attaching method, but not all of
them.
