I have a strange (to me) problem. I recently purchased a rebuilt
4.2 liter engine for my 1986 XJ6. The guy who rebuilt it seemed
to know what he was doing and paid attention to details(no
missing bolts or washers). After I installed the engine I
noticed if the car idled for a few minutes when you rev’ed the
engine it would smoke like all get out. It doesn’t seem to smoke
whne driving expect when I stop for red lights…then a puff and
then it’s all gone. If the idle speed is kept high, it smokes
less or not at all. I talked to the fella I bought the engine
from and he told me that after he rebuilt the head it smoked and
he took the engine out and found a sticking oil control ring that
is why the engine was completely rebuilt this time (he junked
that car). I am wondering if the real problem was faulty valve
seals and that is why it smoked the first time. If anyone has
seen this kind of wierd smoking please post your findings. One
other thing is that it loses oil pressure when braking on a
downhill grade (the oil is full). I am wondering if the oil
baffle (in the oil pan) door could be stuck open? Thanks much!–
Dr Payne
San Diego, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
I’m really far behind on my mail, but my car does this too. The Previous
Owner of my car had done a valve job but didn’t go any lower, so I just
chalked it up to a tight top and a loose bottom with oil seeping through
the rings. How bad is your oil consumption? Mine is about a quart every
500 miles of highway driving. I’m wondering if the guy who did the rebuild
on your engine really did everything that he said. Did he show you the
receipts for the parts he bought to do the rebuild? Also on your oil
pressure drop problem when braking, could be due to your oil filter. There
was some discussion on this not long ago, and I’ve had the same problem with
the pressure dropping lately after I used a generic filter on mine. Since
you’ve supposedly got a new rebuilt engine anyway, try using a good filter
the next time you change your oil.
Danny Herrin
Macon, MO
1984 VDP----- Original Message -----
From: drpayne@cox.net
To: xj@jag-lovers.org
Sent: Saturday, July 06, 2002 10:46 AM
Subject: [xj] XJ6 smoking at idle
I have a strange (to me) problem. I recently purchased a rebuilt
4.2 liter engine for my 1986 XJ6. The guy who rebuilt it seemed
to know what he was doing and paid attention to details(no
missing bolts or washers). After I installed the engine I
noticed if the car idled for a few minutes when you rev’ed the
engine it would smoke like all get out. It doesn’t seem to smoke
whne driving expect when I stop for red lights…then a puff and
then it’s all gone. If the idle speed is kept high, it smokes
less or not at all. I talked to the fella I bought the engine
from and he told me that after he rebuilt the head it smoked and
he took the engine out and found a sticking oil control ring that
is why the engine was completely rebuilt this time (he junked
that car). I am wondering if the real problem was faulty valve
seals and that is why it smoked the first time. If anyone has
seen this kind of wierd smoking please post your findings. One
other thing is that it loses oil pressure when braking on a
downhill grade (the oil is full). I am wondering if the oil
baffle (in the oil pan) door could be stuck open? Thanks much!
Dr Payne
San Diego, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from Danny Herrin sent Fri 19 Jul 2002:
I have the same oil pressure problem also when parking on a steep
hill downward after a minute or so. I removed pan, replaced o
rings on pump pickup pipes, checked specs on pump and problem
persists. I assume that after oil is used in the pickup (below
the damper plate) and all oil is too far forward, pump runs dry.
None of my other cars suffer from this problem on the same hill.
British engineering I think. I hope I’m wrong but in the meantime
I don’t suggest idling downward on steep hills.–
willdy
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from Danny Herrin sent Fri 19 Jul 2002:
I have the same oil pressure problem also when parking on a steep
hill downward after a minute or so. I removed pan, replaced o
rings on pump pickup pipes, checked specs on pump and problem
persists. I assume that after oil is used in the pickup (below
the damper plate) and all oil is too far forward, pump runs dry.
None of my other cars suffer from this problem on the same hill.
British engineering I think. I hope I’m wrong but in the meantime
I don’t suggest idling downward on steep hills.
You’re joking…?
Even with the return passages clogged up (may cause smoking), there
can’t be enough room in the head to deplete 8 liters of oil to that
extent?? Cracks in the lower part of oil feeder pipe?
BTW, with a similar problem on my old Cortina it was the upper seal of
the dipstick. Slid upwards it showed plenty of oil where little was…
