[xj] 1971 Daimler XJ6 Series 1 restoration

XJ
1

I�ve been at it again � bought another Jaguar/Daimler. This is a
very sweet Series 1, 1971 and therefore UK road tax exempt. It�s in
2.8lt auto guise, short wheelbase. MoT till Nov 2007 but currently
not roadworthy as the engine running is very rough.

First impressions: a marvellous find, a little gem.

Did a bit of digging. Found the floors to be OK. The inner sill at
places were glass-fibre covered. There�s one rust hole on the
driver�s inner sill. Should be easy to repair. The rear wheelarch
on the inside is also rotted in a few places. Again no headache.

The radiator came out easily and looks OK. May not need a re-core.
The doors are good. The driver�s door has this round knob for
opening the quarter window. This knob has broken and I�m trying to
get to it. The bottom door card has come off but how do I remove
the upper card (covered in black leather?).

http://www.jag-lovers.org/snaps/snap_view.php3?id=1190101552
http://www.jag-lovers.org/snaps/snap_view.php3?id=1190101752--
teddykan
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2

In reply to a message from teddykan sent Tue 18 Sep 2007:

Most interesting find, Richard, well done!

Hope the rough running isn’t the standard 2.8 ‘hole in the piston’
issue :slight_smile:

I’ve a suspicion that the top card is held in place by some
microscopic self tappers on the glass side, but I could be
confusing it with something else…–
The original message included these comments:

opening the quarter window. This knob has broken and I�m trying to
get to it. The bottom door card has come off but how do I remove
the upper card (covered in black leather?).

–
al mclean '93 XJS 4.0 - '84 4.2 Daimler - '84 DD6
Telford, United Kingdom
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3

In reply to a message from almcl sent Tue 18 Sep 2007:

Hi Al
Bought it from keith of XJ Restorations, down near Hailsham, for
not a lot.

Can you tell me more about the ‘hole in the piston’ problem? My
friend Rodney (of Staplehurst) and his friend suspect it’s to do
with the pistons, probably broken rings. Would a compression test
reveal a knackered piston? I may have to get a compression tester.

So far I’ve been chasing bodywork; mechanics I’m hopeless on, for
the time being.

Thanks–
teddykan
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4

In reply to a message from teddykan sent Tue 18 Sep 2007:

Not an expert here, but as I understand it the 2.8 was prone to
carbon build up on the pistons if driven gently, a problem that
wasn’t revealed in testing as Norman and the others were
not ‘gentle’. This build up could cause burning of the piston
crown and and lead to a hole.

I imagine that a compression test with a bit of oil in the bores
will show if there’s a problem.–
The original message included these comments:

Can you tell me more about the ‘hole in the piston’ problem? My
friend Rodney (of Staplehurst) and his friend suspect it’s to do
with the pistons, probably broken rings. Would a compression test
reveal a knackered piston? I may have to get a compression tester.

–
al mclean '93 XJS 4.0 - '84 4.2 Daimler - '84 DD6
Telford, United Kingdom
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5

In reply to a message from teddykan sent Tue 18 Sep 2007:

Richard:

Man, are you obcessed? Dumb question as the answer is obvious. No
worse than the rest of us, well, maybe a bit!!

That is a very attractive car. and of course, being MOT exempt
makes it even better!!

I hope this doesn’t mean that work on the Double six will cease!
We are looking forward to your day of triumph wnen you drive that
one!

As to compression testing. A dry test will reveal any leaksand the
cylinder(s) that is leaking. but, it will not isolate a bad valve
(s) fromn leaking rings or worse, a hole in a piston(s).

The wet test will temporarily seal leaky rings. If the cylinder(s)
remain low it is a valve leak.

If the engine runs, a holed piston will make itself known with
voluminous blue smoke from the exhaust.

When you go shopping for a compression guage you may want to get
a ‘‘leak down’’ guage. It is a sophisticated compression guage. It
allows the cylinder to be charged with compressed air. Then you
watch the guage and see if holds compression or leaks down. If it
leaks, an ear to the intake may detect a noise of escaping air
denoting a leaky intake. An ear to the exhaust may detect a leaky
exhaust valve. An ear to the crankcase filler may detect air going
through hole in a piston, usually noisy, or more subtly, leaking
rings.

The compression guage will help detect a holed piston, as the
reading will be zero!

More adventures!!

Carl–
The original message included these comments:

very sweet Series 1, 1971 and therefore UK road tax exempt. It�s in
2.8lt auto guise, short wheelbase. MoT till Nov 2007 but currently
not roadworthy as the engine running is very rough.
First impressions: a marvellous find, a little gem.
Did a bit of digging. Found the floors to be OK. The inner sill at
places were glass-fibre covered. There�s one rust hole on the
driver�s inner sill. Should be easy to repair. The rear wheelarch
on the inside is also rotted in a few places. Again no headache.
The radiator came out easily and looks OK. May not need a re-core.
The doors are good. The driver�s door has this round knob for
opening the quarter window. This knob has broken and I�m trying to

–
Carl Hutchins
Walnut Creek, California, United States
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6

That was exactly it. Apparently just the way the stroke and rod ratios
worked out there was a lot of dwell time at the top of the stroke, so
the pistons in a 2.8 ran the hottest of the whole XK range. If the car
was driven gently around town ( as lots fo them were when new) deposits
built up on the pistons. After driving around town you then decided to
merge onto the Motorway the deposits would burn off; that combined with
the extra load could burn a hole through the piston top.

Jaguar played around with all sorts of things to fix this, and the
solution that finally fixed it was dropping the 2.8 and bringing in the
3.4 as the economy engine.

Craig

almcl wrote:>In reply to a message from teddykan sent Tue 18 Sep 2007:

Not an expert here, but as I understand it the 2.8 was prone to
carbon build up on the pistons if driven gently, a problem that
wasn’t revealed in testing as Norman and the others were
not ‘gentle’. This build up could cause burning of the piston
crown and and lead to a hole.

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7

In reply to a message from Craig Talbot sent Tue 18 Sep 2007:

great looking car!!! I think the color is great for a jag. I
want to repaint mine in red, but we’ll see.–
Dalton in LA, CA 1987 XJ6 base model
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8

In reply to a message from teddykan sent Tue 18 Sep 2007:

What a nice old ser1. A beauty.
The top door panel is held on with three or four small pozidrive
screws into the door frame.–
The original message included these comments:

I�ve been at it again � bought another Jaguar/Daimler. This is a
get to it. The bottom door card has come off but how do I remove
the upper card (covered in black leather?).

–
John Testrake 74XJ12L rhd
St.Louis, United States
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9

teddykan wrote:

In reply to a message from almcl sent Tue 18 Sep 2007:

Hi Al
Bought it from keith of XJ Restorations, down near Hailsham, for
not a lot.

Can you tell me more about the ‘hole in the piston’ problem? My
friend Rodney (of Staplehurst) and his friend suspect it’s to do
with the pistons, probably broken rings. Would a compression test
reveal a knackered piston? I may have to get a compression tester.

Compression test is a must in this case, Richard…

Run ‘dry’ and ‘wet’ it will reveal something, substantially higher ‘wet’
pressures indicate a cylinder wear problem - no change a valve problem.
also the readings between the cylinders has some significance in
assessing a problem. However, with a holed piston you will practically
have no pressure in the affected cylinder - and it won’t change wet or
dry. Unfortunately neither will it if it has dropped a valve…

Ultimately, whatever the reason for pressure anomlies; only a ‘head off’
inspection can resolve what is what. But the compression test may also
reveal that nothing is amiss, and the running problem has other
causes…:slight_smile:

Frank
xj6 85 Sov Europe (UK/NZ)===================================================
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10

In reply to a message from Frank Andersen sent Wed 19 Sep 2007:

I worked on the lovely old Daimler on Sunday again. Got my
compression tester and got these readings (no 1 is front of engine
at radiator end):
no 1 115psi
no 2 125psi
no 3 65psi (dry), 115psi (oil down bore)
no 4 125psi
no 5 125psi
no 6 120psi

So it looks like worn cylinder bore, or dodgy rings, on no.3.

Rodney and I also sorted out the rough running. Carb 1 (frontmost)
had a sticking float chamber stopc0ck which was flooding the
engine. After freeing this off she ran sweetly and plenty of power.
But as this fed no.3 cylinder the excess fuel could have
contributed to the higher wear in this (but then, how did nos 1 and
2 get away with it?). Despite the smoother running, there was still
a lot of puffing at the crankcase breather � is combustion gas
getting past the piston to pressurise the crankcase? Rod�s friend
advises that once it gets warm, the gaps will close up and it
should puff less? How does this sound? Do I need to check the
piston rings and bore via an engine strip?

Got a bit of cosmetic bodywork to sort out on this one, look at the
rot in the headlamp bowl. Shall try to clean out the radiator and
reinstall it for some hot running tests next Sun. Got quite a bit
of cosmetic welding around the rotted front headlamp socket, the
radiator cross member (under radiator), the rear tank covers.

http://www.jag-lovers.org/snaps/snap_view.php3?id=1190702016--
teddykan
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11

In reply to a message from teddykan sent Tue 25 Sep 2007:

Don’t know if this will of much help to you but I once had a
tractor that had sat for a long time. Came time to start it up and
had great difficulty with it. Checked the compression as you have
done and found two of the cylinders really down on compression.

Decide to continue on to try and start it anyway, felt I had
nothing to lose by doing so. Let it run for quite a while after
finally getting it going. Rechecked the compression after that and
found everything had returned to normal.

Apparently on mine it was either sticky piston rings or just
something like a crude build up on the face of the valves that had
been held open all the time the engine had just sat unused. Giving
the engine a good running had allowed it too either burn the crud
off the face of the valves or had just loosened up the piston rings.–
Bob
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12

teddykan wrote:

In reply to a message from Frank Andersen sent Wed 19 Sep 2007:

I worked on the lovely old Daimler on Sunday again. Got my
compression tester and got these readings (no 1 is front of engine
at radiator end):
no 1 115psi
no 2 125psi
no 3 65psi (dry), 115psi (oil down bore)
no 4 125psi
no 5 125psi
no 6 120psi

So it looks like worn cylinder bore, or dodgy rings, on no.3.

Rodney and I also sorted out the rough running. Carb 1 (frontmost)
had a sticking float chamber stopc0ck which was flooding the
engine. After freeing this off she ran sweetly and plenty of power.
But as this fed no.3 cylinder the excess fuel could have
contributed to the higher wear in this (but then, how did nos 1 and
2 get away with it?). Despite the smoother running, there was still
a lot of puffing at the crankcase breather � is combustion gas
getting past the piston to pressurise the crankcase? Rod�s friend
advises that once it gets warm, the gaps will close up and it
should puff less? How does this sound? Do I need to check the
piston rings and bore via an engine strip?

In principle, Richard - as long as the engine runs to your satisfaction
you don’t really ‘have’ to do anything - though I shouldn’t really be
saying that…:slight_smile:

Obviously there is considerable wear, or broken piston rings in #3.
Actually it is #4 as Jaguar counted the cylinders from the rear - but
that’s by the way. There will be considerable blow-by, increasing
crankcase pressure which will also contribute to high oil consumption.
Causing increased sooting up of plugs and combustion chambers…

Also, while broken piston rings may already have scored the bore;
further use may cause further damage as more of the rings might break
away. The ‘proper’ course of action is of course to remove the head and
inspect the bore. If there is no damage, the rings may be OK - but
severely worn as might be the bore. Which can be judged, in addition to
the ‘wet’ pressure test, visually by the ridge left at the top of the bores.

The rich running may certainly be a cause of excessive wear - but more
likely as a contributory. The rings themselves may have failed for a
variety of reasons - they are hard working members of the family…

In makeshift mode, and with no apparent bore damage the single piston
can be removed, inspected and new rings/piston installed without a strip
down - and with the engine in situ. However, it requires removal of the
head and the sump - and on an xk the latter is an awkward proposition…

Such a ‘repair’ is doable and in an appropriate situation fair to fine.
But the appropriate action is of course a full stripdown, examination
and a rebuild to specs. With a replacement block or engine overhauled or
second hand - with the usual drawbacks - as an alternative…

Frank
xj6 85 Sov Europe (UK/NZ)===================================================
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13

In reply to a message from Frank Andersen sent Tue 25 Sep 2007:

Richard:

I agree with Bob and Frank. it cluld be just simply stuck rings in
3 or 4 as either of you count. Then some running with fresh oil can
free them up and result in a serviceable engine.

But, I disagree that warming up will reduce the ‘‘blow by’’. As the
oil gets thinner with temperature, the blow by will increase. but,
blowby in itself is not a disaester, it is merely a symptom of worn
mechanical parts.

So:

  1. drive it as it is and add oil from time to time. I’ve done that
    on more than one car and got good service.

  2. Fix the #4 by removing the head and sump. Not easy as Frank
    says, but doable. Others have done it.

  3. Pull it out and rebuild it.

  4. Get a better engine and install it. I hear they are plentiful at
    a good price in UK.

There is another way, but I will not mention it on the grounds, it
may incriminate me!!

Good going, one more for your fleet!!

Carl–
The original message included these comments:

I worked on the lovely old Daimler on Sunday again. Got my
compression tester and got these readings (no 1 is front of engine
at radiator end):
no 1 115psi
no 2 125psi
no 3 65psi (dry), 115psi (oil down bore)
no 4 125psi
no 5 125psi
no 6 120psi

–
Carl Hutchins
Walnut Creek, California, United States
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14

On piston aircraft engines where we do compression checks every 100
hours, I ignore a low reading on a single cylinder,especially if it
has been sitting over a winter or something. Same with valve settings.
Fresh oil and a few hours running or even once around the pattern and
recheck that same cyl. will usually do it.
Stuff under an exhaust valve from pulling the plug and turning it
over; sticky rings from old oil; even simply the ring end gaps being
lined up temporarily…
give it a chance and drive it a little while, would be my suggestion.
A little Mystery Oil added to the fuel helps sometimes on the radials.
My observation is: an oil change and a little run in the country does
a lot of good sometimes, just as the cheapest overhaul of an engine
that’s running crappy sometimes simply is a plug change…
Carl; warming up tightens up the clearances/rings/pistons…gives a
truer running temperature picture.
I won’t even waste labor doing a compression test on a cold engine
(and the engine is usually fine when hot)
No answers;just food for thought!!
Bill
Homer, Alaska
alaskaseaplanes.comOn Sep 25, 2007, at 7:29 AM, cadjag wrote:

In reply to a message from Frank Andersen sent Tue 25 Sep 2007:

Richard:

I agree with Bob and Frank. it cluld be just simply stuck rings in
3 or 4 as either of you count. Then some running with fresh oil can
free them up and result in a serviceable engine.

But, I disagree that warming up will reduce the ‘‘blow by’’. As the
oil gets thinner with temperature, the blow by will increase. but,
blowby in itself is not a disaester, it is merely a symptom of worn
mechanical parts.

So:

  1. drive it as it is and add oil from time to time. I’ve done that
    on more than one car and got good service.

  2. Fix the #4 by removing the head and sump. Not easy as Frank
    says, but doable. Others have done it.

  3. Pull it out and rebuild it.

  4. Get a better engine and install it. I hear they are plentiful at
    a good price in UK.

There is another way, but I will not mention it on the grounds, it
may incriminate me!!

Good going, one more for your fleet!!

Carl

The original message included these comments:

I worked on the lovely old Daimler on Sunday again. Got my
compression tester and got these readings (no 1 is front of engine
at radiator end):
no 1 115psi
no 2 125psi
no 3 65psi (dry), 115psi (oil down bore)
no 4 125psi
no 5 125psi
no 6 120psi

–
Carl Hutchins
Walnut Creek, California, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/
donate04.php –

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15

Argh!
Got interrupted by the phone and hit send on the previous post
without deleting !!
Sorry Admin., and sorry Gang !!
BillOn Sep 25, 2007, at 12:25 PM, William de Creeft wrote:

On piston aircraft engines where we do compression checks every 100
hours, I ignore a low reading on a single cylinder,especially if it
has been sitting over a winter or something. Same with valve settings.
Fresh oil and a few hours running or even once around the pattern
and recheck that same cyl. will usually do it.
Stuff under an exhaust valve from pulling the plug and turning it
over; sticky rings from old oil; even simply the ring end gaps
being lined up temporarily…
give it a chance and drive it a little while, would be my suggestion.
A little Mystery Oil added to the fuel helps sometimes on the radials.
My observation is: an oil change and a little run in the country
does a lot of good sometimes, just as the cheapest overhaul of an
engine that’s running crappy sometimes simply is a plug change…
Carl; warming up tightens up the clearances/rings/pistons…gives a
truer running temperature picture.
I won’t even waste labor doing a compression test on a cold engine
(and the engine is usually fine when hot)
No answers;just food for thought!!
Bill
Homer, Alaska
alaskaseaplanes.com

On Sep 25, 2007, at 7:29 AM, cadjag wrote:

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16

William de Creeft wrote:

On piston aircraft engines where we do compression checks every 100
hours, I ignore a low reading on a single cylinder,especially if it
has been sitting over a winter or something. Same with valve settings.
Fresh oil and a few hours running or even once around the pattern and
recheck that same cyl. will usually do it.

Which makes me wonder why the check is done, Bill - and if you take off
in this condition…:slight_smile:

The Air Firce catchphrase used to be; ‘if there is doubt - there is no
doubt’…? :slight_smile:

Frank
xj6 85 Sov Europe (UK/NZ)===================================================
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17

Frank,

When we are talking about a 9, 18, 28 or an engine with more cylinders, one cylinder
being a bit low is not unusual. Also we are not talking about an awful lot of
compression on these engines, with many being around 7.0-1, not the 9.0-1 that we
are used to in our Jaguars. The compression in my aircraft engine is 6.7-1, so not a
lot of compression there at anytime.

What Bill mentioned is usual treatment when a cylinder is lower than some of the
others after sitting over winter. The test flight is “in the pattern” as he said, and that
means within easy landing distance of the airport. This is done after a descent
ground run and if everything else feels ok the best way to check the engine out is in
the air.

Also remember that many of these engines cannot be run at full power, or at least
cannot be run at full power for long on the ground. The brakes simply will not hold the
airplane at full power on the ground, so for a real test it has to go into the air.

If there is a real doubt, we never take off, period. If we are trying to get the carbon
out or exercise a cylinder to see if its going to come back to normal pressures, then
what Bill mentioned is acceptable.

Joe A
A&P (aircraft engineer)
ATP (airline transport pilot)
Jag ownerOn 26 Sep 2007 at 20:26, Frank Andersen wrote:

William de Creeft wrote:

On piston aircraft engines where we do compression checks every 100
hours, I ignore a low reading on a single cylinder,especially if it
has been sitting over a winter or something. Same with valve settings.
Fresh oil and a few hours running or even once around the pattern and
recheck that same cyl. will usually do it.

Which makes me wonder why the check is done, Bill - and if you take off
in this condition…:slight_smile:

The Air Firce catchphrase used to be; ‘if there is doubt - there is no
doubt’…? :slight_smile:

Frank

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18

In reply to a message from joeaksa@attglobal.net sent Wed 26 Sep 2007:

Joe & Bill:

Amazing!! But, how about the smaller Franklins & Lycomings?

I recall a flight with an army pilot in his L19 spotter. He
decicided to land in a farmer’s field because of low oil pressure!
He added the oil and took off. I walked to the next town and took a
bus!

Now, if I know that an engine has a shaky cylinder or two, that’s
what I am going to do. No matter how many other good’uns!

I read recently of an impromptu repair of a light plane engine
involving the replacement of a piston and rod. It turned out to be
the wrong part. Result, one of those bad landings, no one walked
away.

And as to low compression engines, that’s fine. but, a different
reading on one or two means either something is wrong with them or
with the others. Not good. I like the ‘‘doubt’’ phrase.

Carl–
The original message included these comments:

When we are talking about a 9, 18, 28 or an engine with more cylinders, one cylinder
being a bit low is not unusual. Also we are not talking about an awful lot of
compression on these engines, with many being around 7.0-1, not the 9.0-1 that we
are used to in our Jaguars. The compression in my aircraft engine is 6.7-1, so not a
lot of compression there at anytime.

–
Carl Hutchins
Walnut Creek, California, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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19

In reply to a message from cadjag sent Wed 26 Sep 2007:

As an ‘‘also airplane pilot and plane part owner’’, we had to replace
our engine recently due to reaching it’s time before overhaul
(TBO). We put in a factory new engine as it had been overhauled
twice before and we wanted the newest modifications this time.

We do a ‘‘lotto’’ and the loser has to do the first hour or two of
flight testing and new engine run in. We are blessed with three
local airports located withing ‘‘glide’’ distance should one have
to ‘‘land early’’ due to problems.

We believe in the ‘‘no doubt rule’’ and keep the plane in shape
around that rule. The story about there are ‘‘no old bold pilots’’ is
really true. Compression leak down testing is done by us first and
then the AP at annual time, so we know what is happening. We have
to fly the plane and it our rear end on the line so the
owners ‘‘participate’’ as much in the maintenance as legally
possible.

Keeping good records from compression time to the next time, doing
the testing the same way with the same gauges helps in making sense
of the results.–
The original message included these comments:

And as to low compression engines, that’s fine. but, a different
reading on one or two means either something is wrong with them or
with the others. Not good. I like the ‘‘doubt’’ phrase.

–
'71 XJ6 383/200R, '74 XJ6 383/700R, '74 Nova SS Glendora, CA
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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20

Carl,

A lot of it has to do with your personal experience with the engine. Bill was talking
about an engine that has been sitting for a while and in this situation its usually
corrected by running the engine a while then either re-checking the compression or
even taking it up in the air. There was nothing wrong with the engine when it was
stored, so whats going to change in the interim?

Problem is that the engines cannot usually be taken to full power on the ground.
One, the brakes will not hold it and two there is not enough cooling air coming in the
engine cylinder area to take the engine to full power.

Another thing is that on many radial engines, the bottom 2-3 cylinders on each bank
may be full of engine oil after sitting. When its time to fly again we remove these
spark plugs and clean them, and let the oil drain out for a while. Sitting like this fills
everything with oil and any compression reading you are going to get will be different
from that of the cylinders that were not soaked in oil during the winter. The
compression was fine when you shut the engine down in the fall and with no reason
to feel that there has been a problem since, you do a ground run or test flight then
check everything on the engine again to confirm that its ok.

One last thing. We are not talking about an engine that has all the cylinders at 160
and one at 30. We are talking about one that has all the cylinders at 78/80 and
possibly one around 60/80 or 64/80. In the aircraft world we put 80 psi in the cylinder
and read what it holds, in this case anywhere from 60 to 78 psi.

Difference in the old “L-birds” as we call them is that they have a flat engine, horiz
opposed aircooled engine much like the old Corvair or VW engines. Four or six
cylinders, they are old farm tractor tech and using magnetos designed in the 1930’s
and low compression engines. My personal airplane was made in this era and has
one of these engines on it.

JoeOn 26 Sep 2007 at 17:00, cadjag wrote:

In reply to a message from @joeaksa sent Wed 26 Sep 2007:

Joe & Bill:

Amazing!! But, how about the smaller Franklins & Lycomings?

I recall a flight with an army pilot in his L19 spotter. He
decicided to land in a farmer’s field because of low oil pressure!
He added the oil and took off. I walked to the next town and took a
bus!

Now, if I know that an engine has a shaky cylinder or two, that’s
what I am going to do. No matter how many other good’uns!

I read recently of an impromptu repair of a light plane engine
involving the replacement of a piston and rod. It turned out to be
the wrong part. Result, one of those bad landings, no one walked
away.

And as to low compression engines, that’s fine. but, a different
reading on one or two means either something is wrong with them or
with the others. Not good. I like the ‘‘doubt’’ phrase.

Carl

The original message included these comments:

When we are talking about a 9, 18, 28 or an engine with more cylinders, one cylinder
being a bit low is not unusual. Also we are not talking about an awful lot of
compression on these engines, with many being around 7.0-1, not the 9.0-1 that we
are used to in our Jaguars. The compression in my aircraft engine is 6.7-1, so not a
lot of compression there at anytime.

–
Carl Hutchins

===================================================
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

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