Greetings All, I was looking at my front cat yesterday and noticed .
The motor is burning lean, the inside is chalk white (both ends)
The screen holes are closed on about half of the screen mesh. I
didn’t take a long screw driver to see if the carbon would flake
off easy, and the blocked holes are random with the exception of
the center.I am wondering (I do that alot these days) if there is
any thing I can put into the converter to clean it up.Any
suggestions on the easiest way to cut the insides out if it is
clogged as I’m not going to replace it unless it fails emissions.I
will correct the lean problem when I finish rebuilding the front
end , also is the charcoal in the canister the same as what you
would find at a pet store for fish tanks.If so I think I’ll try
cutting the canister open and replacing the charcoal and epoxy it
back together.The archives didn’t have much on the converter
question and a member said that with the charcoal canister he put
carb cleaner in sloshed it around drained it out and it worked
fine .Thanks for any input.
Best Regards
Robert Barclay
Elkton , Maryland–
Jaggid 82 XJ6
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
I think a new convertor is called for. Our 86 had about what you describe and
I believe it contributed to raising the exhaust side temps enough to loosen 2
valve tappet guides.–
Alex
79xj6L SII (BRG + wires)
86xj6 SIII (Black)
61 Sprite MkII (Red)
Menlo Park, Calif.
Jaggid wrote:
Greetings All, I was looking at my front cat yesterday and noticed .
The motor is burning lean, the inside is chalk white (both ends)
The screen holes are closed on about half of the screen mesh. I
didn’t take a long screw driver to see if the carbon would flake
off easy, and the blocked holes are random with the exception of
the center.I am wondering (I do that alot these days) if there is
any thing I can put into the converter to clean it up.Any
suggestions on the easiest way to cut the insides out if it is
clogged as I’m not going to replace it unless it fails emissions.I
will correct the lean problem when I finish rebuilding the front
end , also is the charcoal in the canister the same as what you
would find at a pet store for fish tanks.If so I think I’ll try
cutting the canister open and replacing the charcoal and epoxy it
back together.The archives didn’t have much on the converter
question and a member said that with the charcoal canister he put
carb cleaner in sloshed it around drained it out and it worked
fine .Thanks for any input.
Best Regards
Robert Barclay
Elkton , Maryland
In reply to a message from Jaggid sent Wed 24 Aug 2005:
Nice to know that carbon canister is nothing too complicated. I
have a 50lb bag of activated carbon here at work that is industrial
grade used for vapor absorption. A few pounds of it may make its
way home in my cat I thought that it might be prudent to change
out my canister as it is probably original, or age unknown. A
small cutting wheel, or a steady hand with a sharp utility knife
ought to do the job. Thanks for the info !–
The original message included these comments:
end , also is the charcoal in the canister the same as what you
would find at a pet store for fish tanks.If so I think I’ll try
cutting the canister open and replacing the charcoal and epoxy it
Hello all, Doe’s anyone have a suggestion on how to remove the
inside of front cat on my xj6.It’s partly clogged and I think the
motor would perform alot better without it even if it wasn’t
clogged. One cat is bad enough 2 is overkill.What is behind the
screens once they are removed? I’ve never taken a converter apart
before , any help as always is greatly appriciated.
Robert Barclay
Elkton , Maryland–
Jaggid 82 XJ6
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from Jaggid sent Mon 29 Aug 2005:
A an adendum to the above question: What would be the
effects of getting rid of the catalytic converter? Emissions
aside,is the cat converter a necessary piece of equipment?–
82 Series III XJ6 140k+
Berkeley, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
The catalysts only role is emission reduction, it takes care of CO and
unburned HC’s, and burns them, and converts the CO to CO2. It does add
some backpressure to the exhaust system, and certainly adds to the
underhood heat.
Depending on where you live, there may be inspections that require the
presence of all the original emission equipment.
Craig
92 VDP
Ryan A. wrote:>In reply to a message from Jaggid sent Mon 29 Aug 2005:
A an adendum to the above question: What would be the
effects of getting rid of the catalytic converter? Emissions
aside,is the cat converter a necessary piece of equipment?
In reply to a message from Jaggid sent Mon 29 Aug 2005:
I’ve thought about that, one problem you may encounter is
the need for a 4 wire O2 sensor. The front cat keeps the one
wire hot enough to work, but take that away, and you would
need to figure out how to wire in a 4 wire. When I’m ready
to do it, I hope to find a non federalized down pipe. I’ve
never seen one, but I’ll bet they exist.–
83 XJ6/ 87 325is
Denton, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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Nope, not at all. The O2 sensor has to be before the cat, if it was
after the cat it wouldn’t know how rich or lean the engine is since the
emissions have been altered by the cat.
The European cars without cat also didn’t run lamda feedback, so they
have different ECU’s and no O2 sesnors.
Craig
92 VDP
EricF wrote:>In reply to a message from Jaggid sent Mon 29 Aug 2005:
I’ve thought about that, one problem you may encounter is
the need for a 4 wire O2 sensor. The front cat keeps the one
wire hot enough to work, but take that away, and you would
need to figure out how to wire in a 4 wire. When I’m ready
to do it, I hope to find a non federalized down pipe. I’ve
never seen one, but I’ll bet they exist.
In reply to a message from Craig Talbot sent Tue 30 Aug 2005:
The main difference between a 4 wire sensor and a 1 wire is
the heating element. Normally, cars with a long distance
between the manifold and the cat used the 4 wire (I think
now, all cars use 4 wire sensors). By removing the pre-cat
you are creating exact scenario that called for a 4 wire.
Since you seem to know about the Euro cars, do they use a
header type down-pipe in place of the highly restrictive y +
pre-cat one the Federalized cars use?–
83 XJ6/ 87 325is
Denton, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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In reply to a message from EricF sent Tue 30 Aug 2005:
You raised a good question.I don’t have anything to lose by gutting
the old converter out. If it fails emissions I’ll replace it with a
new one.I might have a problem passing if I went with a non federal
down pipe ,as Craig mentioned and in Maryland you have to have the
original set up.But if it passes with a gutted out front cat who’s
to know the differance.I need to know what is behind the top and
bottom screens before I start ripping and tearing.I have a single
wire senser on my 82 at the manifold and I don’t think it will
cause me any trouble . I’m guessing that Jaguar put two cats on to
avoid any import problems with U.S. emissions.The 2nd cat is bigger
than the single one on my 86 pickup and a fellow lister told me I
shouldn’t have any problems passing emissions with only the back
cat.I just need to find a way to cut the insides out.I’m thinking
of using a hole saw .If I can get it around the curves and bends.
I’ve read some where in the archives that if you remove the sensor
at the manfold that you should have very little or no back pressure
coming out the O2 hole if the cats are clear.All in all I think
that 2 cats are overkill and not needed creating poorer performance
and tappet guide and heat problems.Correct me if I’m wrong.The non
fed down pipe might be the easiest way to go, if the car passes
they’re not likely to go poking around counting converters. The
last emissions test I had here in Maryland they drove the truck up
on rollers swung a fan in front of the front grill put it in 1st
gear ran it up to about 4 grand for what I thought was way too long
a period of time, shut it down and sent me on my way.I think it
might not be legal in the U.S.to sell the down pipes w/o the
cat.Importers may not be allowed to ship non fed into the U.S.
Thanks
Robert–
The original message included these comments:
I’ve thought about that, one problem you may encounter is
the need for a 4 wire O2 sensor. The front cat keeps the one
wire hot enough to work, but take that away, and you would
need to figure out how to wire in a 4 wire. When I’m ready
to do it, I hope to find a non federalized down pipe. I’ve
never seen one, but I’ll bet they exist.
Since you seem to know about the Euro cars, do they use a
header type down-pipe in place of the highly restrictive y +
pre-cat one the Federalized cars use?
Non-cat cars use a much less radical Y, with the two branches bascially joining up where the pipe becomes horizontal.
If you go this way, you’ll need to drill a hole and weld in a bung for the oxygen sensor, but the exhaust gasses are plenty hot enough that a single-wire works fine.===================================================
The archives and FAQ will answer many queries on the XJ series…
FAQs: http://www.jag-lovers.org/xjlovers/xjfaq/index.html
Archives: Jag-lovers Forums - Jag-lovers
Cat converters are expensive. I suspect Jaguar used what was necessary to
meet requirements, no more, no less. I think the rear converter …not seen
on the earlier cars, btw…carried a different type of catalyst
altogether, to gain the desired result.
Non-clogged converters really add very little by way of restriction although
the extra heat has long been associated with the tappet guide problem.
Doug Dwyer
Longview, Washington USA
1987 Ser III XJ6
1988 XJS V12From: “Jaggid” rbarxj6@comcast.net
I’m guessing that Jaguar put two cats on to
avoid any import problems with U.S. emissions.
.All in all I think
that 2 cats are overkill and not needed creating poorer performance
and tappet guide and heat problems.Correct me if I’m wrong.
I’ve had conversations about this with Pete Bond at Coventry West. IIRC, he
said he doesn’t carry the Euro down pipes but can get them, implying that
there’s no problem with importing them. Don’t take my memory as gospel,
though. I don’t. Give them a call. No affiliation blah, blah.
In reply to a message from Doug Dwyer sent Tue 30 Aug 2005:
I believe all Jaguar’s of this era were imported to meet CA
emmission standards. If you arn’t in CA should be no problem
removing the rear cat converters, leaving the front. This should
reduce back pressure and at the same time keep the car legal for
non CA applications.–
Jaguar Jeff - '95 XJS 6.0L Conv / '87 VDP 4.2L
Wilmington, DE, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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If you’re right about the emissions part, I’d rather eliminate the front cat
and install a less restrictive Euro-style down pipe, keeping the rear cat,
or perhaps substituting a more modern, more efficient high-pass version. BT-----Original Message-----
From: owner-xj@jag-lovers.org [mailto:owner-xj@jag-lovers.org]On Behalf Of
Jaguar Jeff
Sent: Tuesday, August 30, 2005 8:18 PM
To: xj@jag-lovers.org
Subject: Re: [xj] front catalitic converter
In reply to a message from Doug Dwyer sent Tue 30 Aug 2005:
I believe all Jaguar’s of this era were imported to meet CA
emmission standards. If you arn’t in CA should be no problem
removing the rear cat converters, leaving the front. This should
reduce back pressure and at the same time keep the car legal for
non CA applications.
You may be right about the California emissions thing, but be careful about
removing any emissions equipment. Even though two converters may not have
been originally required in all States, I’ll wager that removing one or both
is still violation of federal law, even if you live in a state which does
require both to be accounted for…technically speaking.
Probably not an issue unless you live in an inspection state and come across
a savvy smog tech…
As these cars get older and older I think some of these issues may
become…well… non-issues.
Doug Dwyer
Longview, Washington USA
1987 Ser III XJ6
1988 XJS V12From: “Jaguar Jeff” jeff.bolmeyer@comcast.net
I believe all Jaguar’s of this era were imported to meet CA
emmission standards. If you arn’t in CA should be no problem
removing the rear cat converters, leaving the front. This should
reduce back pressure and at the same time keep the car legal for
non CA applications.
Note also that the 3-4 wire sensors also provide a good ground. On the 1-wire
units, some of us have clamped a copper wire to the case and grounded it to
the frame nearby. The assumed ground path through the manifold is notoriously
poor.–
Alex
79xj6L SII (BRG + wires)
86xj6 SIII (Black)
61 Sprite MkII (Red)
Menlo Park, Calif.
EricF wrote:
In reply to a message from Jaggid sent Mon 29 Aug 2005:
I’ve thought about that, one problem you may encounter is
the need for a 4 wire O2 sensor. The front cat keeps the one
wire hot enough to work, but take that away, and you would
need to figure out how to wire in a 4 wire. When I’m ready
to do it, I hope to find a non federalized down pipe. I’ve
never seen one, but I’ll bet they exist.
The item number is 7997310574 (1982-93 Jaguar XJ12/XJS New
Exhaust Downpipes - Upgrade).
Dirk de Boer–
The original message included these comments:
need to figure out how to wire in a 4 wire. When I’m ready
to do it, I hope to find a non federalized down pipe. I’ve
never seen one, but I’ll bet they exist.
Sorry, those are for a 12 cylinder, the manifolds for a 6 cylinder are
different and these pipes won’t fit. I have those downpipes on my V12,
and I had to drill a hole and weld in some bungs for the oxygen sensors.
After that exercise my exhaust guy said that he would never work on
another V12 Jaguar again.
Craig
92 VDP
Dirk de Boer wrote:>In reply to a message from Cannara sent Thu 1 Sep 2005:
This might just be the part for which you are looking:
The item number is 7997310574 (1982-93 Jaguar XJ12/XJS New
Exhaust Downpipes - Upgrade).
Dirk de Boer
The original message included these comments:
need to figure out how to wire in a 4 wire. When I’m ready
to do it, I hope to find a non federalized down pipe. I’ve
never seen one, but I’ll bet they exist.
I thought that it might be prudent to change