[xk] Fuel Filler Pipe and Filter questions

XK
1

I’m still fixing up a few annoying little snags in my XK150 which
was fully restored some time ago and wonder if anyone can help with
these .Trying to trace one of those annoying ‘‘petrol (gas) smells’’
and I’ve checked just about every connection. However , looking at
the filler pipe I notice the following :- Underneath the external
flap in the fuel filler box is a hole, which is connected from
inside the trunk to the fuel tank. Now, I assume this is the fuel
tank vent. However in the metal tube from the fuel filler box to
the 2inch or so diameter rubber hose connecting to the tank is a
short spigot about 6mm diameter just poking out inside the trunk
above the point where the rubber hose is connected . This is open
and not connected to anything and I would say allowing the fuel
tank to vent directly into the trunk. I can’t find a detail in any
parts manual - can anyone please tell me what this is for
( assuming that the seperate vent system is correct as I’ve
described above)? Also the rubber pipe connecting the metal filler
to the tank appears to be made of water hose and has 2 kinks in it
as it bends to connect to the tank , although doesn’t seem to have
any adverse affect when filling the tank. Should this be a more
rigid material?

Secondly - Iv’e noticed that the fuel line from the tank to the
glass filter bowl ( it’s a triple SU set up) enters at the front
and the supply to the carbs goes out through the back - exactly
opposite to the way it should ( according to the parts manuals) .
I intend to make up some new pipes to get the layout correct, but
the question is - would this be having any effect on fuel flow as
the filter bowl appears to have different entry and exit
configuration??
Thanks

David Chadwick XK150, Mk2 3.8, XJR–
david chadwick
nsw, Australia
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–

2

David,
I imagine the 150 should be pretty much the same or similar to the 120 in
this area, so I will describe mine.

When you lift the filler flap, you should see a hole in the lowest corner.
This is a tube that lets rain water drain out under the wing onto the road,
not inside the boot (trunk).

In a higher spot inside the filler box there should be another tube. This
should be bent in a curve or otherwise configured so rainwater is not likely
to go down it. On the underside inside the boot you should see the other end
of this short tube, which is connected by a small diameter hose to the vent
tube from the fuel tank. The vent tube in the fuel tank is located somewhere
on top or near the top.

Fuel tanks need to vent, and the place they chose to vent them is inside the
filler box, not inside the boot. Well actually the venting continues out
through that rainwater drain tube and on out to the outside air.

Your big filler hose kinks may be due to having the wrong hose. Can you post
a picture? Some of our 150 experts will help you if the correct hose is
straight or has pre-formed bends in it. My 120 hose is straight but the tank
neck is not quite perfectly in line with the filler neck.

The glass bowl filter is usually marked with flow arrows or IN and OUT. The
idea is dirt should fall to the bottom of the bowl where you can see it, and
the bowl can hold quite a lot of dirt before there is enough to stop the
flow. Reverse flow would leave the dirt on top of the filter screen where
you can’t see it and would probably be clogged up sooner.

Rob Reilly - 679187

3

Hello David,
First, regarding your fuel tank, the XK150 had two types, an internally
vented and an externally vented model. If you car is an early XK150, it is
the same tank that was used on the 140. On the early models, in the fuel
filler box, there will be only one hole, a drain hole at the bottom, which
exits out into the wing wheel well area via short piece of rubber hose. This
allows water and excess fuel spillage out onto the ground (not an
environmentally correct system!!!). Later, the fuel filler box hinge was
changed, as well as the filler tube seal, and a second hole, above the main
fuel filler tube was added. A rubber hose returns from that hole to the fuel
tank at the top LH side of the tank. The possibility exists that you have an
early tank in late car or vice versa. However, if you have the early style,
even with a short length of tubing to the wheel well, some back pressure can
cause fuel fumes to enter the boot area under the trim. I would suggest you
change the early type fuel seal to the later “bulb” type for a more
effective seal on the fuel filler tube. It’s very simple, just fit the bulb
over the existing metal piece that hold the flat early seal. If you have the
later tank and have the two holes, route a rubber line back to the tank, and
renew the bulb to ensure a good seal.
If you have fumes from the engine compartment, and you are sure you have no
leaks, well I’m afraid that its just the fact that even a properly working
system will occasionally belch fuel out those overflow tubes and onto the
frame below the carbs and then onto the ground. As to you fuel line routing,
I don’t quite understand what the modification was or why, but I would
return it to the correct layout, as I think all the parts are available from
the usual suppliers. But make sure you’re looking at the layout for you car
serial number and engine model, as there different versions.

Jerry Oliver
Olympia, WA
S830079 - 1958 XK150 OTS
S830318 - 1958 XK150 OTS
S836996DN - 1961 XK150 FHC
UE1S24964 - 1974 V12 OTS
CT54404L - 1966 Triumph TR4A-----Original Message-----
From: owner-xk@jag-lovers.org [mailto:owner-xk@jag-lovers.org] On Behalf Of
david chadwick
Sent: Friday, April 20, 2007 1:25 AM
To: xk@jag-lovers.org
Subject: [xk] Fuel Filler Pipe and Filter questions

I’m still fixing up a few annoying little snags in my XK150 which
was fully restored some time ago and wonder if anyone can help with
these .Trying to trace one of those annoying ‘‘petrol (gas) smells’’
and I’ve checked just about every connection. However , looking at
the filler pipe I notice the following :- Underneath the external
flap in the fuel filler box is a hole, which is connected from
inside the trunk to the fuel tank. Now, I assume this is the fuel
tank vent. However in the metal tube from the fuel filler box to
the 2inch or so diameter rubber hose connecting to the tank is a
short spigot about 6mm diameter just poking out inside the trunk
above the point where the rubber hose is connected . This is open
and not connected to anything and I would say allowing the fuel
tank to vent directly into the trunk. I can’t find a detail in any
parts manual - can anyone please tell me what this is for
( assuming that the seperate vent system is correct as I’ve
described above)? Also the rubber pipe connecting the metal filler
to the tank appears to be made of water hose and has 2 kinks in it
as it bends to connect to the tank , although doesn’t seem to have
any adverse affect when filling the tank. Should this be a more
rigid material?

Secondly - Iv’e noticed that the fuel line from the tank to the
glass filter bowl ( it’s a triple SU set up) enters at the front
and the supply to the carbs goes out through the back - exactly
opposite to the way it should ( according to the parts manuals) .
I intend to make up some new pipes to get the layout correct, but
the question is - would this be having any effect on fuel flow as
the filter bowl appears to have different entry and exit
configuration??
Thanks

David Chadwick XK150, Mk2 3.8, XJR

david chadwick
nsw, Australia
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–

4

Hmmmm—something here sounds strange,
The XK120 has two holes in the fuel filler box: one at the lower corner
to drain water and spilled fuel to the ground, the other at the upper corner
to vent the tank via a hose connecting to a tube attached to the top of the
tank. Is it true that this arrangement was deleted from the 140 and early
150 models? If so, why, and how were those tanks vented? If the filler tube
seal worked properly, what kept the tank from collapsing, or the other side,
fuel starvation?
Greg Bernier
XK120 DHC, Mark IX, XJ6 Ser.III

From: “Jerry Oliver” JerrysJaguar@comcast.net
Reply-To: xk@jag-lovers.org

Hello David,
First, regarding your fuel tank, the XK150 had two types, an internally
vented and an externally vented model. If you car is an early XK150, it is
the same tank that was used on the 140. On the early models, in the fuel
filler box, there will be only one hole, a drain hole at the bottom, which
exits out into the wing wheel well area via short piece of rubber hose.
This
allows water and excess fuel spillage out onto the ground (not an
environmentally correct system!!!). Later, the fuel filler box hinge was
changed, as well as the filler tube seal, and a second hole, above the main
fuel filler tube was added. A rubber hose returns from that hole to the
fuel
tank at the top LH side of the tank. The possibility exists that you have
an
early tank in late car or vice versa. However, if you have the early style,
even with a short length of tubing to the wheel well, some back pressure
can
cause fuel fumes to enter the boot area under the trim. I would suggest you

Jerry Oliver

-----Original Message-----
From: owner-xk@jag-lovers.org [mailto:owner-xk@jag-lovers.org] On Behalf Of
david chadwick
However , looking at>the filler pipe I notice the following :- Underneath the external
flap in the fuel filler box is a hole, which is connected from
inside the trunk to the fuel tank. Now, I assume this is the fuel
tank vent. However in the metal tube from the fuel filler box to
the 2inch or so diameter rubber hose connecting to the tank is a
short spigot about 6mm diameter just poking out inside the trunk
above the point where the rubber hose is connected . This is open
and not connected to anything and I would say allowing the fuel
tank to vent directly into the trunk.

5

In reply to a message from Greg Bernier sent Sun 22 Apr 2007:

Hi Greg
Yep, the 140s (mine anyway), as Jerry has mentioned seem to
be the same as early 150s, only has one short rubber drain
tube coming downward from the bottom corner of the filler
box, through the wheel arch sheet metal, draining any excess
fuel during a fill-up straight onto the ground.
The only means of venting the tank seems to be by a well
planned air leak, through an imperfect seal of a flat
rubber washer hanging down by a spring from the bottom of
the filler lid.
The flat rubber washer even has a cross hatch pattern of
tiny grooves molded into its lower surface where it touches
the top edge of the metal filler tube leading down to the
tank, to ensure an imperfect air seal.–
The original message included these comments:

tank. Is it true that this arrangement was deleted from the 140 and early
150 models? If so, why, and how were those tanks vented? If the filler tube
seal worked properly, what kept the tank from collapsing, or the other side,

–
Gary Grant S818919DN
Ottawa, Canada
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –

6

Gee Greg, maybe its just one of many design items that made the 150 superior
to the 120…just kidding. You’ll have to ask the engineers on the list
how it works, I just know there are the two types listed in the parts manual
and by suppliers (search SNG Barratt for example), and since I own one of
each type (early and late) I can verify the manual and describe the
difference.

Jerry Oliver
Olympia, WA
S830079 - 1958 XK150 OTS
S830318 - 1958 XK150 OTS
S836996DN - 1961 XK150 FHC
UE1S24964 - 1974 V12 OTS
CT54404L - 1966 Triumph TR4A-----Original Message-----
From: owner-xk@jag-lovers.org [mailto:owner-xk@jag-lovers.org] On Behalf Of
Greg Bernier
Sent: Saturday, April 21, 2007 5:45 PM
To: xk@jag-lovers.org
Subject: RE: [xk] Fuel Filler Pipe and Filter questions

Hmmmm—something here sounds strange,
The XK120 has two holes in the fuel filler box: one at the lower corner

to drain water and spilled fuel to the ground, the other at the upper corner

to vent the tank via a hose connecting to a tube attached to the top of the
tank. Is it true that this arrangement was deleted from the 140 and early
150 models? If so, why, and how were those tanks vented? If the filler tube

seal worked properly, what kept the tank from collapsing, or the other side,

fuel starvation?
Greg Bernier
XK120 DHC, Mark IX, XJ6 Ser.III

From: “Jerry Oliver” <@Jerry_Oliver2>
Reply-To: xk@jag-lovers.org

Hello David,
First, regarding your fuel tank, the XK150 had two types, an internally
vented and an externally vented model. If you car is an early XK150, it is
the same tank that was used on the 140. On the early models, in the fuel
filler box, there will be only one hole, a drain hole at the bottom, which
exits out into the wing wheel well area via short piece of rubber hose.
This
allows water and excess fuel spillage out onto the ground (not an
environmentally correct system!!!). Later, the fuel filler box hinge was
changed, as well as the filler tube seal, and a second hole, above the main
fuel filler tube was added. A rubber hose returns from that hole to the
fuel
tank at the top LH side of the tank. The possibility exists that you have
an
early tank in late car or vice versa. However, if you have the early style,
even with a short length of tubing to the wheel well, some back pressure
can
cause fuel fumes to enter the boot area under the trim. I would suggest you

Jerry Oliver

-----Original Message-----
From: owner-xk@jag-lovers.org [mailto:owner-xk@jag-lovers.org] On Behalf Of
david chadwick
However , looking at
the filler pipe I notice the following :- Underneath the external
flap in the fuel filler box is a hole, which is connected from
inside the trunk to the fuel tank. Now, I assume this is the fuel
tank vent. However in the metal tube from the fuel filler box to
the 2inch or so diameter rubber hose connecting to the tank is a
short spigot about 6mm diameter just poking out inside the trunk
above the point where the rubber hose is connected . This is open
and not connected to anything and I would say allowing the fuel
tank to vent directly into the trunk.

7

In reply to a message from Jerry Oliver sent Sun 22 Apr 2007:

Thanks to all those who responded especially Terry Hilton and Terry
McGrath off line. It seems the overflow pipe under the filler flap
was in fact connected to the tank vent and the vent spigot just
inside the trunk ( boot) is not connected to anything. So… a
simple fix.

regards–
david chadwick
nsw, Australia
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –