[xj40] Help identify this part - Fuel Filler Latch Box mechanism

Hi All

I’m hoping someone out there knows the proper name and more
importantly, where to get a new one!

http://www.jag-lovers.org/v.htm?1345869011

(Sorry about the poor quality of the pics, I was in a hurry
and didn’t hold the camera very still.)

The part in question is the grey/silver barrel:

1 1/2’’ inches in length
1 1/8’’ inches depth on the interior of the barrel
1/2’’ outside diameter of barrel
3/16’’ interior diameter of barrel opening

This part is responsible for retracting the pin on 88/89 MY
XJ40’s when the fuel lid door is pressed down on a pressure
plate, causing a circuit to be completed which supplies
power to the part and by electro-magnetics(?) causes the pin
to be retracted and the fuel door is released.

Obviously I disassembled the entire Fuel Filler Latch Box
and the latching assembly to take the pics. The pin was
absolutely 100% covered in black gunk, no wonder it no
longer sprung back out any longer. Shame on me, poor
maintenance.

Spent 30 minutes with a piece of sanding sand paper to get
it clean. Cleaned the barrel, reassembled the unit (latching
assembly only), plugged it back into it’s connector and
tested. Got nothing. No retraction of the pin when
pressure is applied to the pressure point. I went into the
eBook section and read the guide again to confirm the
process. The fuse is not blown and never has been a
problem, so that only leaves the cylinder or the little
black box (I guess the selonoid) as being bad.

I’m assuming the cylinder suffered damage and corroded
inside where the connections are. There is no way to take
it apart to check the connections, it’s appears to be fused
together.

I’m hoping there is an outside chance that I can get one of
these locally and keep my schedule of getting the tank back
in the vehicle before Hurricane Issac shows up in the middle
of next week.

I was able to get some info off of the barrel, there is what
appears to me a logo, a capital ‘‘M’’ with a square drawn
around it, follow by the numbers that appear to read
‘‘W80002’’. That’s the most I could get from it.

So, what is the proper name and where do I get one? Or
perhaps I need to get both the barrel and the black solenoid.–
Rob Evenson, '89 XJ40/XJ6
Mobile, AL, United States
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In reply to a message from Rob Evenson, sent Sat 25 Aug 2012:

Rob,

Afraid I can’t really help you.

AFAIK, the solenoid / plunger device was only supplied as
part of the complete fuel filler latch box assembly - and
even they they are no longer available from Jaguar according
to the JDHT parts catalogue.

I guess you are stuck with opening the flap manually from
inside the trunk? Unless you can pick up a good one from a
scrapper - but are there any good ones still in existence I
wonder?–
The original message included these comments:

I’m hoping someone out there knows the proper name and more
importantly, where to get a new one!
http://www.jag-lovers.org/v.htm?1345869011


Bryan N, '91 Sovereign 4.0 L, RHD
Cambridgeshire, United Kingdom
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In reply to a message from Bryan N sent Sat 25 Aug 2012:

Hi,

If the part in question is BEC7531

It is available from David Manners Ltd for a mere �316.00

And as Bryan said it is only available as a complete unit

Ouch…

Cheers Steve–
The original message included these comments:

AFAIK, the solenoid / plunger device was only supplied as
part of the complete fuel filler latch box assembly - and


1992 - XJ40 Sovereign - 4.0ltr - Vin 665981 - RHD
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In reply to a message from Guernsey sent Sat 25 Aug 2012:

Steve,

You may be correct about the availability of that latch box
from David Manners - but note that it is not a normally
stocked item and I suspect the ‘‘4 Days’’ indicates that they
would try to obtain it from Jaguar - and Jaguar say it is ‘‘NLA’’.–
The original message included these comments:

If the part in question is BEC7531
It is available from David Manners Ltd for a mere �316.00
And as Bryan said it is only available as a complete unit


Bryan N, '91 Sovereign 4.0 L, RHD
Cambridgeshire, United Kingdom
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In reply to a message from Rob Evenson, sent Sat 25 Aug 2012:

Rob…

Wow!! 316 Pounds ($500) seems rather cheeky for such a small part,
(you have to watch our British cousins as once in awhile they still
get upset and try to stick it to us for that whole Declartion of
Independence thing!)… I’m only joking Bryan, you know we love you
guys!

Now Rob you said, ‘‘There is no way to take it apart to check the
connections, it’s appears to be fused together.’’…for half a
large I think I would find a way.

Is it metal? Take it to a machine shop and I’m sure for a very
reasonable fee they can open it up and figure out a way to reattach
it for you.

In my experience I’ve found that very few assemblies can withstand
an intelligent and determined disassembly–
Groove
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In reply to a message from Grooveman sent Sat 25 Aug 2012:

Hi,

Just came in for a break from restoring the tank and thought
I would check on responses. I did find a few of the full
blown assembly’s here in the states and they ranged from
$350 to $450 USD.

The latch pin quit working a little over a year ago and my
quick fix then was a stack four 1/4’’ round magnets and
placed in the opposite corner of the hinge; worked very
well.

I think my best bet is to leave out the pin and fill the
hole with silicon and recall my magnets into duty. I would
love to fix the latch box and have it operational, put
another notch in the belt and call for victory, but alas it
won’t be so today…

Thanks to all, I’ll be posting additional photos in the next
few days of the tank restoration. Never want to do this
project again.–
The original message included these comments:

Wow!! 316 Pounds ($500) seems rather cheeky for such a small part,
Groove


Rob Evenson, '89 XJ40/XJ6
Mobile, AL, United States
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In reply to a message from Rob Evenson, sent Sat 25 Aug 2012:

i did what you have, which is use magnets on the lid to keep it
down and a locking fuel cap for security.
i did strip my down once and get it working after it stopped, but
within 6 months, it stopped again.
the early latch boxes are a pain in the ass and a waste of time,
along with the BFM s on these cars. more trouble than their worth!
it did find someone selling the electronics for these once, at a
huge fraction of your price, if I find it again, i ll post it here.–
XJ40 SOVEREIGN 4.0 1990 (G-REG) SOLENT BLUE
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In reply to a message from Rob Evenson, sent Sat 25 Aug 2012:

look at eBay item 110880736357 It’s the right voltage and
diameter, maybe a little shorter. But it may do the trick.–
The original message included these comments:

The part in question is the grey/silver barrel:
1 1/2’’ inches in length
1 1/8’’ inches depth on the interior of the barrel
1/2’’ outside diameter of barrel
3/16’’ interior diameter of barrel opening
This part is responsible for retracting the pin on 88/89 MY
XJ40’s when the fuel lid door is pressed down on a pressure
plate, causing a circuit to be completed which supplies
power to the part and by electro-magnetics(?) causes the pin
to be retracted and the fuel door is released.


Pete Peterson 70E(193K) 88XJ40s(270K & 256K) 94XJ40 (122K)
Severna Park, Maryland, United States
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In reply to a message from Jaguarpete sent Sat 25 Aug 2012:

Have just renewed mine with I belive what was the last one local
supplier had on the shelf

As you say these only come as part of the whole unit

Someone in UK did produce a replacement part (the pin operating
electronics as a project and tried to market via one of the jag
specialist outfits in UK many years ago
I have the prototype on my shelf and have actually never tried it
however having tried to look at one of mine that did fail have
ascertained that the problem is almost certainly the pressure plate
which is at the bottom of the tube and is activated when you press
the lid down - the pressure plate loses its ‘spring’ and then the
contact will not allow the activation of the pin
The pressure ‘plate’ is similar to those found in some of the older
tv remote controls and I did toy with the idea of trying to replace

Problem being is that all the electronics on the board are encased
in epoxy and trying to remove taht would inevitably do even more
damage

Nigel–
1987 XJ40 3.6 Auto Sov SAJJHALH3AA512874
Singapore, Singapore
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In reply to a message from Rob Evenson, sent Sat 25 Aug 2012:

Rob,

A few thoughts that may or may not be of any help:

  1. There are only a few things that can go wrong with a
    solenoid: loss of supply power; open or shorted coil; or a
    frozen plunger/armature due to corrosion/foreign matter or
    deformation.

  2. Have you checked that the solenoid is receiving power to
    unlock at the electrical connector? I assume it should be
    getting 12V.

  3. Have you tested the electrical continuity of the
    solenoid coil? The cylinder contains a bobbin wrapped in
    one long continuous piece of copper wire, with electrical
    connections for each end of the copper wire to the two wires
    that extend from the solenoid body. In the photo it looks
    as though there may be two wires coming out of the end of
    the solenoid plus a ground wire connected to the side. If
    you have an ohmmeter, you can test for continuity across the
    two wires that come out of the white plastic end of the
    solenoid. You should get a modest resistance, perhaps as
    much as a few thousand ohms. If there is no continuity, you
    have confirmed that either the coil of copper wire is broken
    somewhere, or one of the connections of the copper wire to
    the external terminals has broken. If there is continuity
    but the resistance is small, say only a few ohms, the coil
    may be shorted so that it can’t generate the necessary
    magnetic field to retract the plunger.

  4. I agree with Groove that you should find a way to open
    the solenoid! It appears that the unit would have
    originally been assembled by sliding the copper-wire-wound
    bobbin into the outer metal sleeve. If there are no obvious
    metal tabs securing the sleeve to the white plastic base,
    the base may have been press-fit into the cylinder, or some
    adhesive may have been applied around the base to form a
    seal. Carefully heating the metal sleeve around the base
    end with a soldering iron may soften the adhesive or plastic
    enough to allow you to push the coil assembly out of the
    sleeve (using the plunger rod to push).

  5. A local electric motor repair shop can easily rewind a
    solenoid coil, but so can you. Suitable copper magnet wire
    is available from many sources, including those that supply
    electric motor repair businesses and electric guitar pickup
    rewinding services (e.g. www.stewmac.com carries 42 & 43 AWG
    wire for guitar pickups). If you can acquire wire of the
    same gauge, just count the number of turns as you remove the
    old wire, then rewind the same number of turns with new wire
    (after first soldering the end of the new wire to the
    innermost electrical terminal of the solenoid bobbin). Mark
    a line on the end of the bobbin to help you count turns.
    You may be able to mount the bobbin on a variable speed
    drill for faster rewinding. Move the wire back and forth
    across the bobbin to keep the layers of wire reasonably
    flat. They don’t have to be anywhere near perfect.

  6. Showing your solenoid to a knowledgeable appliance
    repairman might turn up a workable replacement from a
    washing machine or?

Good luck!–
The original message included these comments:

This part is responsible for retracting the pin on 88/89 MY
XJ40’s when the fuel lid door is pressed down on a pressure
plate, causing a circuit to be completed which supplies
power to the part and by electro-magnetics(?) causes the pin
to be retracted and the fuel door is released.


Don B : '93 Vanden Plas : (ex-'88 Sovereign)
Franklin, TN, United States
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In reply to a message from Don B sent Tue 28 Aug 2012:

This may seem a simple statememnt however I assume that you have
checked the in line 1 amp fuse that serves this unit ?

Nigel–
1987 XJ40 3.6 Auto Sov SAJJHALH3AA512874
Singapore, Singapore
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In reply to a message from Nigel Snowden sent Wed 29 Aug 2012:

Nigel,

That is a great thought. I hadn’t thought about the
possibility of there being an inline fuse. I don’t know if
a frozen plunger might lead to excessive current draw, but
an electrical short due to moisture ingress certainly could.
Hope to hear from Rob when he’s figured this out.–
The original message included these comments:

This may seem a simple statememnt however I assume that you have
checked the in line 1 amp fuse that serves this unit ?
Nigel


Don B : '93 Vanden Plas : (ex-'88 Sovereign)
Franklin, TN, United States
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In reply to a message from Don B sent Thu 30 Aug 2012:

Don / Nigel

Rob’s first post in this thread stated :-

''The fuse is not blown and never has been a
problem, so that only leaves the cylinder or the little
black box (I guess the selonoid) as being bad. ‘’

So I guess that eliminates that theory. :-)–
The original message included these comments:

That is a great thought. I hadn’t thought about the
possibility of there being an inline fuse. I don’t know if
a frozen plunger might lead to excessive current draw, but
an electrical short due to moisture ingress certainly could.

The original message included these comments:

This may seem a simple statememnt however I assume that you have
checked the in line 1 amp fuse that serves this unit ?


Bryan N, '91 Sovereign 4.0 L, RHD
Cambridgeshire, United Kingdom
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In reply to a message from Bryan N sent Fri 31 Aug 2012:

Bryan,

Good question!

I assumed Rob was describing a fuse in one of the A pillar
panels. I’ve just taken a look at the '88 Electrical Manual
(which I used when I owned an '89 car like Rob’s), and it
appears that there are three relevant fuses:

  1. Fuse 13, Left A Pillar: serves the Fuel Filler Flap
    Interface, as well as other components such as the door
    mirrors; left rear door switch/switch panel/door guard
    light/window motor; left ‘‘E’’ post light (VDP).

  2. Fuse 2, Right A Pillar: serves the Fuel Filler Flap
    Relay, as well as the trunk lock relay and the the door lock
    control unit.

  3. The Inline fuse (1A) shown at the Filler Flap Interface.

The Fuel Filler Flap Relay would also be a suspect
component. According to the schematic it is located in the
left front of the trunk behind the trim panel, presumably
not too far from the filler flap assembly. The relay is
shown as a separate component from the solenoid in the
filler flap interface (which is the component Rob suspects
of failure).–
The original message included these comments:

Rob’s first post in this thread stated :-
''The fuse is not blown and never has been a
problem, so that only leaves the cylinder or the little
black box (I guess the selonoid) as being bad. ‘’
So I guess that eliminates that theory. :slight_smile:


Don B : '93 Vanden Plas : (ex-'88 Sovereign)
Franklin, TN, United States
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In reply to a message from Don B sent Fri 31 Aug 2012:

Don,

Let’s hope that Rob’s car isn’t wired in the way shown in
those circuit diagrams, according to which (in my copy at
least) the battery power from fuse 13 in the left fuse box
on the Brown/slate wire is connected to the same pin on the
4-way connector at the ‘filler flap interface’ as the Black
ground wire!

That will never work! :-)–
The original message included these comments:

I assumed Rob was describing a fuse in one of the A pillar
panels. I’ve just taken a look at the '88 Electrical Manual
(which I used when I owned an '89 car like Rob’s), and it
appears that there are three relevant fuses:

  1. Fuse 13, Left A Pillar: serves the Fuel Filler Flap
    Interface, as well as other components such as the door


Bryan N, '91 Sovereign 4.0 L, RHD
Cambridgeshire, United Kingdom
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In reply to a message from Bryan N sent Sat 1 Sep 2012:

Yowsah!

Bryan, you’re right! (as always!)

My schematic also shows that the battery power and ground
both connect to pin LS14-1 BEFORE the 1A fuse! Obviously,
the car cannot be wired that way.

Rob, we can’t wait to hear how you solve the issue!–
The original message included these comments:

Let’s hope that Rob’s car isn’t wired in the way shown in
those circuit diagrams, according to which (in my copy at
least) the battery power from fuse 13 in the left fuse box
on the Brown/slate wire is connected to the same pin on the
4-way connector at the ‘filler flap interface’ as the Black
ground wire!
That will never work! :slight_smile:


Don B : '93 Vanden Plas : (ex-'88 Sovereign)
Franklin, TN, United States
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In reply to a message from Bryan N sent Sat 1 Sep 2012:

Guys,

First, Thank you to all for your support and knowledge. The
Jag Lovers forum is the best!!! It amazes me how much in-
depth knowledge is shared here compared to other forums.

In regards to the fuses/relays. The 1 AMP inline fuse has
never been a problem, I will check the others, but am
certain they are all in tact. Keep in mind, the latch box
did work properly for many years. To Bryan’s point, the
connector for the latch box has three wires going to it,
none are doubled up. Additionally, I also reviewed the JDHT schematics and noticed the reference to a specified relay in
the boot. I have no such animal there, in fact the
connector is empty and the cover indicates:

White Base - Acces Ign On (empty, as in no relay)
Blue Base - Brake Light Simul
Green Base - Over Volts

I’m leaning towards the suggestions to dismantle the solenoid and see how bad the condition of the interior of
the barrel is. Don, Thanks for the instructions on how to
rewind the magnetic wire.

I have to get with a friend of mine to show me how the use
the multi-meter. I’m a visual kind of learner and someone
telling me how to work something compared to being shown
how, is a significant difference for me in mastering a task.

I’m having one hell of a time reconnecting the fuel lines to
the tank. Hindsight being what it is, I made a significant
mistake by removing the clips instead of simply turning
them. I read the posts and it just didn’t register with me
the references to turning the clips 90 degrees, I think
when I pulled the clips with force and the angle I had, I
bent them just enough where I’m not getting a good snug fit,
I can insert the lines, they seem tight and seated, but can
still pull the line back out with the clip in proper
position. I’ve ordered new clips and since I’m at it, new o-
rings for the fuel lines.

I refuse to post pics of the fuel tank restoration until I
have the process complete. :)) I need the accomplishment
and satisfaction that all is as it should be; nothing
incomplete. (The tank does look damn good!)

Hope things are well for all you, keep you posted and take
care, write to you soon.–
The original message included these comments:

Let’s hope that Rob’s car isn’t wired in the way shown in
those circuit diagrams, according to which (in my copy at
least) the battery power from fuse 13 in the left fuse box
on the Brown/slate wire is connected to the same pin on the
4-way connector at the ‘filler flap interface’ as the Black
ground wire!


Rob Evenson, '89 XJ40/XJ6
Mobile, AL, United States
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In reply to a message from Don B sent Sat 1 Sep 2012:

Hi,

I saw that Don posted up just before I posted my last entry.
I went out and looked at the connections again and here is
what is:

(harness connector to latch box connector)

black to black
brown/slate to brown/slate (runs through 1 amp fuse)
orange/green to purple/yellow

no wires doubled up on any single pin, I think the schematic
my be wrong.–
The original message included these comments:

In reply to a message from Bryan N sent Sat 1 Sep 2012:
Yowsah!
My schematic also shows that the battery power and ground
both connect to pin LS14-1 BEFORE the 1A fuse! Obviously,
the car cannot be wired that way.
Rob, we can’t wait to hear how you solve the issue!


Rob Evenson, '89 XJ40/XJ6
Mobile, AL, United States
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In reply to a message from Rob Evenson, sent Sat 1 Sep 2012:

Rob,

I’m at a bit of a disadvantage because I don’t have (in fact
never have had) a car with that ‘press-to-open’ fuel filler
flap and the circuitry for it is a bit ‘tricky’. However, I
theorise that the ‘fuel filler flap relay’ shown in the
circuit diagrams is not really necessary for the fuel filler
flap to open when pushed! :slight_smile:

It appears to me that the ‘fuel filler flap interface’
solenoid can only operate when the driver and passenger
doors are in the ‘unlocked’ condition. As soon as those
doors are locked, the ‘fuel filler flap relay’ is energised
to immobilise the ‘fuel filler flap interface’ unit to
prevent the solenoid from ‘popping’ the filler flap - which
I guess from a fuel security point of view makes some sense.
Hence if the ‘fuel filler flap relay’ is missing, the fuel
filler flap should be able to be opened whether the doors
are unlocked or locked.

A secondary function of the ‘fuel filler flap relay’ is
that, in the event that the ‘Inertia Switch’ is triggered,
say, in an accident, the ‘fuel filler flap relay’ will
automatically be energised if the ignition key remains in
the ‘ON’ position to immobilise the ‘fuel filler flap
interface’ unit to prevent the solenoid ‘popping’ the filler
flap - a safety issue I guess.

The ‘fuel filler flap relay’, which ostensibly is in a black
base at the front left corner of the trunk next to the
filler tube, appears to be superfluous to the normal
operation of the ‘press-to-open’ fuel filler flap.

I stand to be corrected on those musings! :-)–
The original message included these comments:

did work properly for many years. To Bryan’s point, the
connector for the latch box has three wires going to it,
none are doubled up. Additionally, I also reviewed the JDHT schematics and noticed the reference to a specified relay in
the boot. I have no such animal there, in fact the
connector is empty and the cover indicates:
White Base - Acces Ign On (empty, as in no relay)
Blue Base - Brake Light Simul
Green Base - Over Volts


Bryan N, '91 Sovereign 4.0 L, RHD
Cambridgeshire, United Kingdom
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In reply to a message from Bryan N sent Sat 1 Sep 2012:

Rob,

Bryan is correct that the fuel filler flap is locked when
the passenger doors are locked, and vice versa. There is no
means to operate it independently of the doors.

It is curious that there is no relay in the relay socket.
If the schematic is correct (big if!), the relay is
necessary to energize the solenoid. When you repair the
solenoid (or you discover that the solenoid coil is actually
fine, the problem was just a frozen plunger), you will
almost certainly have to install a relay in order to restore
operation of the flap.

When your friend has time to show you how to use the
ohmmeter/voltmeter, you can check for 12V at the electrical
connector that supplies the filler flap solenoid between the
Brown/Slate wire and Black ground wire; and also at the
relay socket between the Brown/Green and Green/Purple wires
and between the Purple/Yellow and Green/Orange wires.

I think I can explain Bryan’s question about whether the
flap would be open with the relay missing. My assumption is
that the filler flap solenoid is ‘‘normally extended,’’
meaning that when no power is applied to the solenoid, the
internal spring forces the plunger rod outward to lock the
fuel filler flap. It would then require the application of
12V to energize the coil and retract the plunger rod against
the force of the spring to unlock the flap. If my
assumption is correct, you will only be able to measure 12V
at the solenoid or relay base when the car doors are unlocked.

The reason I assume that the solenoid is normally extended
in the ‘‘lock’’ position is that if it were normally
‘‘retracted,’’ or in the ‘‘open’’ position, then whenever the
car was sitting with the doors locked the filler flap would
be drawing 12 volts to remain locked, which would put a
parasitic current drain on the battery. On second thought,
maybe this is why batteries have always seemed to drain
quickly in my '93…

There is no indication on the schematic that the solenoid is
bi-directional or that there is any sort of logic circuit
that could reverse the voltage to the solenoid to operate it
in both directions. Can you confirm that the plunger rod is
spring loaded?–
The original message included these comments:

It appears to me that the ‘fuel filler flap interface’
solenoid can only operate when the driver and passenger
doors are in the ‘unlocked’ condition. As soon as those
doors are locked, the ‘fuel filler flap relay’ is energised
to immobilise the ‘fuel filler flap interface’ unit to
prevent the solenoid from ‘popping’ the filler flap - which
I guess from a fuel security point of view makes some sense.
Hence if the ‘fuel filler flap relay’ is missing, the fuel
filler flap should be able to be opened whether the doors
are unlocked or locked.


Don B : '93 Vanden Plas : (ex-'88 Sovereign)
Franklin, TN, United States
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