Here is my uncles response. He used to be Toyota Service Manager.
"Yes, I was the Service Manager at a Toyota dealership from about 1970
through 1977 but this appears to be a 1965 model, which was before my time.
Additionally, Toyota dealerships were not prevalent in the Southeast until
the very late 1960s. I don't recall ever having seen a Landcruiser older tan
1969 in my shop. That said, I believe that 1965 was pre-emission controls,
and it should not be a complicated matter, even if this "gas leak from the
filler neck" issue was how a Landcruiser actually came from the factory.
Design issues such as that were not uncommon back then. We often had to do
some unorthodox engineering to overcome some of the "weirdo" stuff that we
saw back in those days.
Fixing this should be pretty straight-forward. Here's three approaches, one
of which should correct the problem:
1). The gas neck and cap should seal tightly. No leak. No exceptions. Easy
to test since the neck is already removed. Put the cap on the neck, hold the
neck upside down, if the cap is vented, put a piece of plastic tape over it
or temporarily plug it in some manner, fill with mineral spirits and see
what happens. DON'T use your finger to cover the vent because the pressure
of holding your finger over the vent hole could temporarily seal the cap
while testing. If the joint between the cap and the neck then leaks, you
need to either flatten/reshape the top of neck so that it fits snug all the
way around to the seal in the cap, or get a cap that fits correctly. Just
because a cap was purchased from a Toyota dealership, especially for a 60s
vintage model, here over 40 plus years later, doesn't mean it is the correct
cap. Who really knows?? Get a cap that fits correctly so that it seals and
won't leak, tested as above.
2). If the cap seals tightly and the issue is that the gas instead comes out
of the vent hole excessively, and you are SURE that you have the correct
(vented) cap, here's another approach: Gas expands and contracts and
provisions must be made for venting or the tank will eventually crack from
bending back and forth due to expansion and contraction, and you will
experience fuel starvation from a vacuum being created in the tank. The fuel
tank could also eventually collapse the tank in on itself. I've seen that
happen. The vehicle's fuel pump will not be powerful enough to over come the
vacuum it and/or the tank could crack from bending. There MUST be
ventilation somewhere to the tank to accommodate that. Due to emission
controls, which started in the very late 60s and early 70s, late model cars
used an auxiliary ventilation system. You've probably seen the charcoal
canisters, filters and piping. That's what it is for. So, if the gas cap
vent is where the gas proves to be leaking from in excess, install an aux
vent system (somewhere in the top end of the tank) and a tight fitting
non-vented cap.
3). If all else fails, modify the filler neck by installing opposing,
alternating, overlapping baffles in the filler neck, something like exampled
below:
Top of filler neck/gas cap
| _|
|_ |
| _|
|_ |
| |
Bottom of neck
The place that boiled out the tank should be able to install the baffles. A
further step is to install baffles IN the tank, slowing the sloshing around
of the fuel.
That's the best I can do. Should give anyone a good start anyhow. Hope it
helps.
Uncle Jerry"
