Hey, gang!
I posted a question about Series V fuel pumps a while back but have now had
the experience of actually attempting to get the original style pump to
work. I obviously had no luck as I am once again seeking assistance and
advise.
To recap, my '67 Series V is currently running a universal electric pump
mounted over the rear axle. It works well but I would rather run the
original mechanical pump if possible. I installed a new original pump last
Friday and bypassed the electric unit. Try as I may, the car would not
start; it would not even pump enough fuel to fill the glass bowl on the
fuel pump itself. We were able to use a vacuum device on the fuel line and
suck enough fuel up to fill the fuel pump and line to the carbs. Finally,
the car started. It idled fine for a while and then we proceeded to rev
the engine to approximately 2000 RPMs and held it there. The engine would
hold that RPM level for about 7 to 10 seconds before it acted like it was
falling on its face. Finally the car started sputtering, even at idle, and
died away. We removed the fuel line from the carbs and, when I cranked the
engine over, fuel just barely trickled out of the line. This is an obvious
fuel starvation problem but, to my mind, one that may have several causes.
Please let me pick your collective brains with the following questions:
1. I've was told by the previous owner, as I stated in the last post about
this, that the reason the pump was changed in the first place was because
the cam lobe that drives the pump had been worn flat. I understand that
there is friction there all the time but, in all honesty, I have a real
hard time believing that is the problem. While we cannot determine how
much wear there is on the lobe without tearing down the engine, we can
tell that there is a lobe there and it does not feel or look to be terribly
grooved or worn. Besides, if a fuel pump arm is going to wear out a cam
lobe in 80,000 miles, doesn't it follow that the cam followers, which exert
much higher pressure on the cam lobes due to the valve springs, would wear
out the other lobes much quicker? I don't seem to have a problem there
although, admittedly, I have not checked the other lobes for wear. The car
does run fine, however, and does not give me a reason to expect trouble in
this area. So, in y'alls expert opinions, what are the chances that I have
a cam lobe problem where the fuel pump is concerned?
2. My car has a spacer between the fuel pump and the block that is
approximately 1/4" thick (a guess as I didn't measure it). I read through
the entire section of the factory workshop manual and, unless I just flat
missed something, the only reference it makes to the fuel pump spacer is
something along the order of "be sure to note the number of joints between
the fuel pump mounting flange and the block face." I am assuming that the
"joints" they are referring to are possibly a number of thin spacers
located between the pump and the block. As I stated previously, my car
only has one. Were there varying thicknesses of these spacers? Can I try
the pump without the spacer or will this damage the camshaft and/or fuel
pump arm? Am I even on the right track here?
3. Upon removing the fuel line from the electric pump, I noticed what
appeared to be a piece of rolled up paper stuck in the inlet port of the
fuel pump (rolled up like a cigarette). I removed it and I remember
thinking that this may have been someone's idea of homeade fuel pressure
regulator. I just threw it onto the ground and went about my business.
When it became obvious that I was going to be forced to reconnect my
electric pump, I picked up this piece of "paper" only to find out it was
not paper at all. Evidently, at some time or another, a previous owner has
used that nasty white gas tank sealer (rubberized coating junk) in the fuel
system. It is reasonble to assume that, if a piece that size can come
adrift and lodge itself in the inlet of the fuel pump, then there could be
and probably is more of that crap floating loose in the tanks and balance
tube, possibly partially clogging the union where the balance tube feeds
the fuel line, right under the tail end of the trunk. It is my
understanding that one of these universal pumps can put out anywhere from 4
to 6 psi, whereas the factory mechanical pump puts out much less. Is it
possible that, if there is a clog in the balance tube or anywhere else in
the fuel system caused by this sealing crap, the mechanical pump is not
strong enough to overcome it, even though the electic pump is able to
overcome it due to its higher psi output? HELP!!!
As anyone can see, I don't know which way to proceed first. Let me just
say that, since I found that sealing garbage in the electric fuel pump, I
am going to remove the entire system and have it cleaned from stem to
stern, whether or not I get to use the mechanical fuel pump. That much
won't be that difficult to do and will eliminate that as a souce of
trouble. But, what about the other points? Please let me know what you
think. I am all ears, guys (and gals)!
Thanks in advance,
Andy Walker
P.S.: By the way, we also tried running the car on the mechanical pump
with the fuel filler cap open to alleviate a possible vapor lock
situation...no help.
This archive was generated by hypermail 2b30 : Tue Sep 05 2000 - 10:05:30 CDT