[xj-s] Fuel Pressure Regulator Removal Question

I was only guessing that it acts as a check valve to maintain
fuel rail pressure after shutdown, to improve hot starts by
preventing fuel
vaporization in the rail.

Yes, I forgot to mention that function.

If you look at each FPR, you will see that fuel flows FROM
the fitting
on the side, TO the fitting at the rear, in each instance. It flows
from the fuel pump into the side of the A Bank FPR and
through the rear
fitting to the fuel rail. Fuel flows from the left fuel rail to the
side fitting of the B Bank FPR, and through the rear FPR
fitting to the
tank return line.

So, they both act to regulate downstream pressure?

I fail to see how the A Bank FPR can act like a damper or
modulator to
affect inlet pressure at the rail. My guess would be that it
opens at a
lower pressure than the B Bank FPR.

A more constant up stream pressure reduces the required
modulation in the rail. To see how this can translate to
better regulation in the rail, you have to consider how
pressure regulators work. In general, pressure regulators (at least of
the
kind I’m familiar with) never really maintain constant pressure.
The reason is there has to be some change in pressure to cause
movement of shaft that controls the flow area at the seat. If
the upstream pressure varies a lot, the second regulator has to
move a lot, meaning that the rail pressure has to change a lot
to effect the required change in flow area. Some here will this as
proportional control.

The two FPR’s DO have different
part numbers and have different rear fittings according to the Parts

Catalogue.

I suspect they are different parts because of mounting differences,
and as you point out, different set points.

And the B Bank FPR should NOT be always open to some degree
as someone
suggested, or there will be no maintenance of rail pressure after
shutdown. It is a spring-operated (vacuum modulated) valve
that doesn’t
open until rail pressure is attained.

Perhaps they meant during engine operation.

Ed Sowell
1976 XJ-S
http://www.efsowell.us/ed/myJag.html

// please trim quoted text to context only

In reply to a message from bigbth sent Tue 26 Dec 2006:

The fuel pumps used on the 1st HE cars was the same type up to the
time they changed to the pump in the tank design.

Chadbourn Bolles
803 798 3044–
The original message included these comments:

regulator. Maybe, and I don�t want to get to far fetched, maybe
the newer pumps were better regulated, who knows. The one thing I


Dr. Chadbourn Bolles
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// please trim quoted text to context only

The first HE fuel rails were entirely different from
Ed’s pre-HE and the newer direct bolt on ones and the
ones you have on the cars now that we are discussing.
There were about three different designs. One of
those designs included the inlet fuel pressure
regulator (FPR). They all worked about the same,
because… the fuel was no good for hot soak
conditions.

I drove many V12s with a fuel pressure gauge taped to
the windshield watching the fuel pressure from
overnight sitting to driving at many different speeds
to hot soak no start. The gauge was a 100 psi gauge
with a large 6 inch dial.

The fuel pressure rose to the max (aprox 36 psi) very
quickly. Like someone hit the gauge needle with a
large hammer. All new cars held pressure over night
with a drop to maybe 30 psi. Driving resulted in a
very steady reading that did not cause movement of the
needle unless you moved the throttle enough to vary
the vacuum causing the last (#2) FPR to raise the
pressure. The needle did not vibrate, shake or wander
with or without the inlet FPR.

A hot soak restart would cause the gauge needle to
vary in a soft movement of about 1 psi as the air
(vapor) was purged from the system.

This unvarying reading was consistent with the
different FI systems tested over the years.

Geoff Green

96 XJ6 X300, 95 XJS 4.0 conv, 61 E-type OTS
International Cabriolet Register Jag92hot@aol.com
3.6 XJS Register paulzimmer@btopenworld.com

// please trim quoted text to context only

George,

Interesting. I also have spent a lot of time watching fuel pressure
gauges
on my car. Never went so far as to tape it to the windshield,
but did leave it in place as I closed the bonnet to go to Starbucks.
Got a lot of interested onlookers as I would leave my latte to go out
and take a reading. Also left it on overnight and through the next
day.
It was like a revisit to a college physics lab, watching the
pressure drop during the night (aha, a leak!), only to come
back as the garage warmed the next day. The leak healed itself and a
magic little pump somewhere came on? No, just
the effect of temperature on fluids. There are some plots of pressure
vs. time
at my Web site.

BTW, I have replaced the preHE “race track” rails with an
HE rail. I had to use the preHE regulator for reasons explained in
my write-up (see Web site). I used a rail from and '83, which had
two regulators, but I believe that design prevailed until the 6.0L
engines with the split rails. Your are right about vapor problems,
according to Roger Bywater. There was a succession of rail designs,
going from the dual race tracks to a single race track, and then to
the
U which, as I said, was used until the late mid 90s when the rails
were split
and joined by a hose connection.

In my conversion, initially I plumbed two preHE regulators in parallel
to feed my
HE rail. One failed, and I replumbed to eliminate it (I can hear Chad
cackling!) after convincing myself one could handle the total return
flow, and besides I didn’t like the plumbing complexity. Works fine,
as nearly as I can tell.

But, I want to say again that just because
we can’t tell the difference due to some change, either by “feel”
or our (relatively) crude instrumentation, doesn’t mean that the
OE design was poorly conceived. I tend to give credit to the engineers
at Jaguar who undoubtedly had better training, experience, and
instruments than we do. Not that they always got it right. indeed,
they
surely didn’t with the initial dual race track rails, a design, BTW,
foisted upon
them by Bosch. But I remain convinced that they were chasing real
daemons
in the FI system in the hellish conditions in that engine bay, and
their efforts should not be casually dismissed with anecdotal
evidence.

Ed Sowell
1976 XJ-S
http://www.efsowell.us/ed/myJag.html

The first HE fuel rails were entirely different from
Ed’s pre-HE and the newer direct bolt on ones and the
ones you have on the cars now that we are discussing.
There were about three different designs. One of
those designs included the inlet fuel pressure
regulator (FPR). They all worked about the same,
because… the fuel was no good for hot soak
conditions.

I drove many V12s with a fuel pressure gauge taped to
the windshield watching the fuel pressure from
overnight sitting to driving at many different speeds
to hot soak no start. The gauge was a 100 psi gauge
with a large 6 inch dial.

The fuel pressure rose to the max (aprox 36 psi) very
quickly. Like someone hit the gauge needle with a
large hammer. All new cars held pressure over night
with a drop to maybe 30 psi. Driving resulted in a
very steady reading that did not cause movement of the
needle unless you moved the throttle enough to vary
the vacuum causing the last (#2) FPR to raise the
pressure. The needle did not vibrate, shake or wander
with or without the inlet FPR.

A hot soak restart would cause the gauge needle to
vary in a soft movement of about 1 psi as the air
(vapor) was purged from the system.

This unvarying reading was consistent with the
different FI systems tested over the years.

Geoff Green

// please trim quoted text to context only

Chad,

I don’t know what you mean by “same type,” but my preHE pump
is definitely different from photos I see of the ex-Tank HE pumps.
For one thing, I have a replaceable check valve that screws into the
pump,
acting also as a hose nipple. The HE systems have no such check valve,
leading me to think that that function is handled by the right bank
regulator.

Ed Sowell

PS: Now, is that a “gotcha” or what :slight_smile:
1976 XJ-S
http://www.efsowell.us/ed/myJag.html

The fuel pumps used on the 1st HE cars was the same type up to the
time they changed to the pump in the tank design.

Chadbourn Bolles

// please trim quoted text to context only

In reply to a message from Ed Sowell sent Wed 27 Dec 2006:

Ed, you will notice that I said HE cars not pre HE cars.
Chadbourn Bjolles
803 798 3044–
Dr. Chadbourn Bolles
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We have had this discussion many time before.

I believe Roger Bywater explained the first regulator design some
time ago.

I don’t remember exactly his explanation, but the impression I got
was that Jaguar later determined the first regulator was not necessary.

Bernard Embden
bernardembden.com

// please trim quoted text to context only

Thanks, everyone, for the input.

Here’s why I ask: my inlet regulator failed outright and I simply removed
it. The car seems to run “fine”…but as was mentioned, and we all know,
running “fine” isn’t necessarily the same as running properly.

I have the car down for a major winter servicing and an attack on a few
issues— the come-n-go idle tremble and a reduction in fuel economy among
them. The idle situation pre-dated the regulator removal but I can’t
remember when the fuel mileage started dropping. Anyhow, we know that
either problem can have many root causes but I was wondering if removal of
the f/p regulator was adding another variable into the mix…which is
already thick enough.

Doug Dwyer
Longview Washington USA
1995 XJR
1988 XJS V12 Coupe

The result is inaccurate fuel delivery at all speeds, higher flow
through the system, and if the fuel was vaporizing in the line at
the lower pressure it will prevent vaporization between the pump
and the inlet regulator.


The original message included these comments:

So, with the inlet regulator removed, this deficiency is manifested…how
?

// please trim quoted text to context onlyFrom: “bigbth” brianh.ted@comcast.net

In reply to a message from Doug Dwyer sent Thu 28 Dec 2006:

I have that idle tremble also. It happens at random intervals and
has no apparent trigger. It seems to be a miss fire but it never
happens while driving and since there should be no change in the
electrical system under load or at idle, I suspect one of the
injectors. I haven�t looked at one of the injectors on my 91 so
I�m not sure if this hypothesis has any merit but I assume they are
little solenoids like the others I have seen.

Let me know if you find the culprit.

Brian–
The original message included these comments:

issues— the come-n-go idle tremble and a reduction in fuel economy among


bigbth
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In reply to a message from Doug Dwyer sent Thu 28 Dec 2006:

On the issue of the dual regulators. The early HE cars only had a
single regulator. In 1985 there was a recall to change the fuel
rail design and the dual regulators were added. The fuel tank also
has a pressure regulator to limit the pressure to around 2 PSI. If
you remove the inlet line on a warm day, the pressure in the tank
is enough to pump a good bit of fuel into the engine compartment.
This is stopped by the addition of the inlet regulator. If it
serves no other purpose that helping to limit the amount of fuel
into the engine compartment during a fire, then it has served a
good purpose and probably the one it was put in there for. As far
as function and affecting the engine running, there should be no
noticeable effect as the left regulator controls the rail pressure.–
The original message included these comments:

Here’s why I ask: my inlet regulator failed outright and I simply removed
it. The car seems to run ‘‘fine’’…but as was mentioned, and we all know,
running ‘‘fine’’ isn’t necessarily the same as running properly.
I have the car down for a major winter servicing and an attack on a few
issues— the come-n-go idle tremble and a reduction in fuel economy among
them. The idle situation pre-dated the regulator removal but I can’t
remember when the fuel mileage started dropping. Anyhow, we know that
either problem can have many root causes but I was wondering if removal of
the f/p regulator was adding another variable into the mix…which is
already thick enough.


Dick Maury , Rebuild Dept., Coventry West, Inc.
Lithonia, GA, United States
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// please trim quoted text to context only

Well, yes I do notice that … now! I was so anxious to nail you
I didn’t read what you said! Sorry.

Ed Sowell
1976 XJ-S
http://www.efsowell.us/ed/myJag.html

Ed, you will notice that I said HE cars not pre HE cars.
Chadbourn Bjolles

// please trim quoted text to context only

In reply to a message from Dick Maury sent Thu 28 Dec 2006:

Dick is almost exactly right but I think he is just a bit
out with the year of the recall which I believe took place
in the 1982/83 period here in the UK and was the second
recall to deal with a spate of under-bonnet fires.

For this second recall Jaguar took to heart a well known
sentiment of Lockheed Aviation�s famous Kelly Johnson -
�when you get a problem kill it dead so the goddam thing
can�t ever come back and bite you again�. The strategy
Jaguar chose might be described as a case of belt, braces,
and a jockstrap over everything.

The new square fuel rail reduced the possibility of fuel
leaks; the distributor venting dealt with any chance of
crankcase vapour build up causing a distributor explosion;
and the incoming regulator eliminated the chance of
pressurized fuel in the feed pipe adding to any conflagration.

The incoming pressure regulator really acted as a sort of
fire door, isolating the pump feed from the fuel rail. It
was not unique to the HE V12 and was found in other
applications � late versions of the Porsche 928 for example.
It was also helpful as a means of damping out noise from the
fuel pump. In this respect it may be significant that the
flat surfaces of a square fuel rail are likely to emit noise
more readily than a fuel rail of circular section.

I always considered the oil vapour theory a bit implausible
really, although I know from personal experience that vapour
collecting in the vee from any slight fuel leakage certainly
could result in such pyrotechnics.

The reason the incoming regulator was deemed redundant for
facelift cars onwards was because the injectors were
attached to the new fuel rail by a more secure socket and O
ring arrangement instead of lengths of hose. Chances of
leakage were therefore greatly reduced.

In all instances the pressure in the fuel rail was solely
controlled by the outgoing regulator � modulated according
to manifold pressure.

Although it will make no difference at all to performance,
if I owned a V12 from the period in question I think I would
sleep more easily if I knew that the incoming regulator was
present.

Many recent production cars (including Jaguars for several
years) have no fuel feedback return nor any pressure
regulator as such. The system pressure is governed by the
ECU from a fuel pressure transducer and a temperature sensor
in the fuel rail, controlling the pump output to produce the
required flow and pressure.–
Roger Bywater / AJ6 Engineering
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// please trim quoted text to context only

Dick sent this to me off-list and I’m passing it along with his permission:

"I certainly look up to Roger as the expert and don’t want to start another
long post of opinions, but I think I might be correct on
this date as far as the USA recall is concerned. Here’s why I think so:

The year 1985 was Jaguar’s 50th anniversary and they wanted to do something
special in the USA in observance. They decided to enter
a 1935 SS1 Jaguar in the Great American Race, going from Los Angeles to New
York over a two-week period. They hired me to prepare
the car and to go along as the alternative driver and navigator. It was a
great event and Mike Cook later told me that it was one of
the most successful competition events they had ever sponsored, as far as
PR and bang for the buck.

The car’s only problems were a broken speedo cable in Chicago and one flat
tire. (Luckily, a new speedo cable was in our spares box
as I had just run out of time to replace it before the race). The final
banquet was held on the Fourth of July at the restaurant on
the top floor of the World Trade Center.

As there were a lot of higher-ups from Jaguar in attendance, I got to hear
some interesting news. One item was that there was about
to be a very large recall of the XJ-S models to update the FI system with a
new design. It is certainly possible that this had
occurred earlier outside of the USA but over here I’m pretty certain it was
in mid-1985. I believe I still have the information and
service records at home indicating when it was done on my 1983, if anyone
is interested. Thanks, Dick"

Best regards,

Gregory Wells 800-331-2193 x103
Coventry West, Inc. Atlanta, GA
Jaguar & Land Rover Parts
(New, Rebuilt & Used) www.coventrywest.com

-----Original Message-----
RogerBywater wrote:

Dick is almost exactly right but I think he is just a bit
out with the year of the recall which I believe took place
in the 1982/83 period here in the UK and was the second
recall to deal with a spate of under-bonnet fires . . .

// please trim quoted text to context only

Roger,

Thanks for the clarifications. I for one was unaware of (or had been
told but forgot) that there was an early HE with a single regulator.
Guess it was the one with a single racetrack rail. Tell me, did it
have a check valve back at
the pump, like the preHE? If not, how was post-shutdown rail pressure
maintained?

Dick is almost exactly right but I think he is just a bit
out with the year of the recall which I believe took place
in the 1982/83 period here in the UK and was the second recall to
deal
with a spate of under-bonnet fires.

The '83 that I harvested my HE rail from had two regulators.

… and the incoming regulator eliminated
the chance of pressurized fuel in the feed pipe adding to any
conflagration.

The incoming pressure regulator really acted as a sort of fire door,

isolating the pump feed from the fuel rail. It was not unique to the

HE V12 and was found in other applications - late versions of the
Porsche 928 for example.

I am having trouble understanding this.

If the scenario is a collision followed by fire the pump would be shut
off
by the inertia switch, so the first regulator would close trying to
maintain
upstream pressure. However, the benefit could be short lived if the
feed
hose burned through. From this perspective, it seems to me that
if fire safety was the main issue it would have been better to locate
it outside the engine compartment, e.g., in the boot.

If the scenario was instead the (more frequent, I believe)
engine fire of mysterious origin, and the driver doesn’t have the
presence
of mind to shut the ignition off, the pump is going to continue
running and
the regulator has no effect at all.

Also, there is a question in my mind of whether something simpler
than a pressure regulator wouldn’t serve as well or better in the
situation of a fire when the pump is off. For example, a check
valve at the pump that doesn’t open until pressure is above 2 psi
would do it. The one used on the pre might be just such a part.

Or, what am I missing here?

It was also helpful as a means of damping out
noise from the fuel pump. In this respect it may be significant that

the flat surfaces of a square fuel rail are likely to emit noise
more readily than a fuel rail of circular section.

So you are saying the first regulator acts fast enough to
dampen the high frequency pressure fluctuations form the pump?

I always considered the oil vapour theory a bit implausible
really, although I know from personal experience that vapour
collecting in the vee from any slight fuel leakage certainly
could result in such pyrotechnics.

You mean in the distributor?

In all instances the pressure in the fuel rail was solely
controlled by the outgoing regulator - modulated according to
manifold pressure.

I have no way of knowing whether it was a design consideration at all,
but
the first regulator will also allow the second one to hold more
uniform
pressure in the rail, at least in principle. This is so because the
more the
upstream pressure varies the more the downstream one has to move in
it’s
effort to maintain set point pressure, and
due to the proportional action this means more deviation from the
set point pressure, i.e., offset. At least that is what my
(mostly analytical) experience tells me. I don’t know the
practical significance in this situation.

Many recent production cars (including Jaguars for several
years) have no fuel feedback return nor any pressure regulator as
such. The system pressure is governed by the ECU from a fuel
pressure
transducer and a temperature sensor in the fuel rail, controlling
the
pump output to produce the required flow and pressure.

I’ve often wondered how that was implemented. Is it varying pump
speed,
or does the pump have some kind of volumetric control?


Roger Bywater / AJ6 Engineering

Ed Sowell
1976 XJ-S
http://www.efsowell.us/ed/myJag.html

// please trim quoted text to context only

Greg, Dick,

Not that it matters all that much, but I know the
'83 XJ-S had two regulators. I harvested an HE rail off an
'83 parts car owned by former list member Ned Wesley. There were
two.

Regarding the story told by the Jaguar Cars people, there were
several FI changes throughout the HE run, in particular the
implementation of compensation for a hot rail. IOW, they weren’t
necessarily
talking about adding a pressure regulator.

Also, the speedo went electronic at some point. Did the '85 still have
a cable?

Ed Sowell
1976 XJ-S
http://www.efsowell.us/ed/myJag.html

Dick sent this to me off-list and I’m passing it along with
his permission:

"I certainly look up to Roger as the expert and don’t want to
start another
long post of opinions, but I think I might be correct on
this date as far as the USA recall is concerned. Here’s why I
think so:

The year 1985 was Jaguar’s 50th anniversary and they wanted
to do something
special in the USA in observance. They decided to enter
a 1935 SS1 Jaguar in the Great American Race, going from Los
Angeles to New
York over a two-week period. They hired me to prepare
the car and to go along as the alternative driver and
navigator. It was a
great event and Mike Cook later told me that it was one of
the most successful competition events they had ever
sponsored, as far as
PR and bang for the buck.

The car’s only problems were a broken speedo cable in Chicago
and one flat
tire. (Luckily, a new speedo cable was in our spares box
as I had just run out of time to replace it before the race).
The final
banquet was held on the Fourth of July at the restaurant on
the top floor of the World Trade Center.

As there were a lot of higher-ups from Jaguar in attendance,
I got to hear
some interesting news. One item was that there was about
to be a very large recall of the XJ-S models to update the FI
system with a
new design. It is certainly possible that this had
occurred earlier outside of the USA but over here I’m pretty
certain it was
in mid-1985. I believe I still have the information and
service records at home indicating when it was done on my
1983, if anyone
is interested. Thanks, Dick"

// please trim quoted text to context only

Ed, the question under discussion is when the recall was done, not what model years it might have covered. The fact that the '83 had
two regs doesn’t really address when they might actually have been installed. I note your point about there being several FI-related
XJ-S recalls, but must also point out I was just posting that for Dick.

I’m more than willing to fade away and let Roger, Dick, and the rest of ya duke this one out! :sunglasses:

The cable-driven speedo was changed to electronic in mid-'81 IIRC.

Best regards,

Gregory Wells 800-331-2193 x103
Coventry West, Inc. Atlanta, GA
Jaguar & Land Rover Parts
(New, Rebuilt & Used) www.coventrywest.com

-----Original Message-----
Ed Sowell posted:

Not that it matters all that much, but I know the
'83 XJ-S had two regulators. I harvested an HE rail off an
'83 parts car owned by former list member Ned Wesley. There were
two.

Regarding the story told by the Jaguar Cars people, there were
several FI changes throughout the HE run, in particular the
implementation of compensation for a hot rail. IOW, they weren’t
necessarily
talking about adding a pressure regulator.

Also, the speedo went electronic at some point. Did the '85 still have
a cable?

// please trim quoted text to context only

Me too. I always thought that even the earliest HEs had two
regulators…

Live and learn :slight_smile:

Doug Dwyer
Longview Washington USA
1995 XJR
1988 XJS V12 Coupe

Roger,

Thanks for the clarifications. I for one was unaware of (or had been
told but forgot) that there was an early HE with a single regulator.

// please trim quoted text to context onlyFrom: “Ed Sowell” EdsJag_12@efsowell.us

In reply to a message from Ed Sowell sent Fri 29 Dec 2006:

Hi Ed and all, in the instance of a fire of mysterious origin, the
fuel pump will stop if the engine is not running. That is unless
someone has done as previous threads have talked about overriding
this feature and putting in a permanent ground. The ECU provides
the ground to the pump relay with the engine running. The inertia
switch cuts power to the fuel injection system overall which
includes power to the pump relay. As far as dampening the pulses of
the pump, the injectors cause pulse waves greater than the pump.
This is very apparent on the six cylinder models where all 6
injectors fire in sequence. The XJ40’s added a dampener in the line
to reduce this. The V12’s don’t pulse together so it is not as big
of a problem. There is a check valve system in place on the HE’s
but it is not of a pressure limiting design. It does however let
the fuel lines maintain pressure when the engine is shut off. In
reading over all of the threads, it is still of my opinion that the
cars fuel system should not be modified whether electrically or
mechanically unless the person doing it has a good understanding of
how the system works. The cars run just fine stock as far as I can
remember. If they are not running properly, changing the design of
the systems is not usually a good idea. Just be safe out there as I
don’t want to be the only one in 20 years with a running XJS as all
of the others have burned up.–
The original message included these comments:

I am having trouble understanding this.
If the scenario is a collision followed by fire the pump would be shut
off
by the inertia switch, so the first regulator would close trying to
maintain
upstream pressure. However, the benefit could be short lived if the
feed
hose burned through. From this perspective, it seems to me that
if fire safety was the main issue it would have been better to locate
it outside the engine compartment, e.g., in the boot.
If the scenario was instead the (more frequent, I believe)


Dick Maury , Rebuild Dept., Coventry West, Inc.
Lithonia, GA, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php

// please trim quoted text to context only

In reply to a message from Doug Dwyer sent Fri 29 Dec 2006:

The early HE cars had a single regulator located right behind the
throttle pedestal. As far as I knew, all were eligible for the
recall modification including the gray market cars. It is rear to
see the early setup now days but they still pop up from time to
time. So even though the early HE’s running down the road now have
two regulators, it is because they had the recall.–
The original message included these comments:

Me too. I always thought that even the earliest HEs had two
regulators…

Live and learn :slight_smile:

Thanks for the clarifications. I for one was unaware of (or had been
told but forgot) that there was an early HE with a single regulator.


Dick Maury , Rebuild Dept., Coventry West, Inc.
Lithonia, GA, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php

// please trim quoted text to context only

Many recent production cars (including Jaguars for several
years) have no fuel feedback return nor any pressure
regulator as such. The system pressure is governed by the
ECU from a fuel pressure transducer and a temperature sensor
in the fuel rail, controlling the pump output to produce the
required flow and pressure.


Roger Bywater / AJ6 Engineering--------------------------------------------------------------------------

That sounds like a good idea.
Returning bucket loads of excess heated fuel from the fuel rail to the
tank is not elegant.
After a long run in hot weather you know you have a very hot tank of
volatile fuel.

How does it work ?
Electronic control of the fuel pump or electronic control of a short
circuiting valve which bleeds off high pressure fuel at the pump outlet
directly back to tank.

Could it be adapted for the XJ-S ?

// please trim quoted text to context only