I was up and out at the shop at 6:00am this morning after my
neighbour helped me install the rebuilt head.
I had everything reinstalled by 3:30 and then I found the problem. #1 and #6 plugs were reversed !!! I cannot belive the car ran
and I even drove it in this condition.
When I tried to set the timing at 3000 rpm that must have bent the
intake valves.
She now purrrrrrrrssssss like a kitten and roars like a car.
Thank you to all who assisted me in this adventure. My wife thanks
you as well since she can now take her for a spin after eight years.
III post a video of the smooth engine tommorow.
Cheers
Michael–
1986 Jaguar XJ6 Sovereign (almost restored)
Whitby Ontario, Canada
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
How did you manage to keep her quiet all those years? My wifs 82 XJ6
has been in the garage with a diff needing replacement for 8 years and
she drives me nuts!!!On Wed, Nov 12, 2008 at 4:35 PM, jag-m elitewindows@rogers.com wrote:
Thank you to all who assisted me in this adventure. My wife thanks
you as well since she can now take her for a spin after eight years.
III post a video of the smooth engine tommorow.
Jim Isbell
“If you are not living on the edge, well then,
you are just taking up too much space.”
The advantage of having extra cylinders firing well! Good news Michael.
Just be glad it wasn’t a V12 with one bank firing and the other
loading a cat convertor with fuel (did I say Marelli?)!–
Alex
79xj6L SII (BRG + wires)
86xj6 SIII (Black)
61 Sprite MkII (Red)
Menlo Park, Calif.
jag-m wrote:
I was up and out at the shop at 6:00am this morning after my
neighbour helped me install the rebuilt head.
I had everything reinstalled by 3:30 and then I found the problem. #1 and #6 plugs were reversed !!! I cannot belive the car ran
and I even drove it in this condition.
When I tried to set the timing at 3000 rpm that must have bent the
intake valves.
She now purrrrrrrrssssss like a kitten and roars like a car.
Thank you to all who assisted me in this adventure. My wife thanks
you as well since she can now take her for a spin after eight years.
III post a video of the smooth engine tommorow.
In reply to a message from jag-m sent Wed 12 Nov 2008:
So it must have been that back-firing that caused the valve to
bend, not a bent valve causing the back-firing ?
Must have been one hell of a bang.
Dave–
The original message included these comments:
I had everything reinstalled by 3:30 and then I found the problem. #1 and #6 plugs were reversed !!! I cannot belive the car ran
and I even drove it in this condition.
When I tried to set the timing at 3000 rpm that must have bent the
intake valves.
Agreed and my gut tells me that something else happened. Back-firing does
not bend valves, or at least not in the 40 years that I have been working on
engines of all types around the world.
Just my 2c worth but something else bent the valves IMHO…
Joe AOn 13 Nov 2008 at 0:28, sparx wrote:
In reply to a message from jag-m sent Wed 12 Nov 2008:
So it must have been that back-firing that caused the valve to
bend, not a bent valve causing the back-firing ?
Must have been one hell of a bang.
Dave
The original message included these comments:
I had everything reinstalled by 3:30 and then I found the problem. #1 and #6 plugs were reversed !!! I cannot belive the car ran
and I even drove it in this condition.
When I tried to set the timing at 3000 rpm that must have bent the
intake valves.
–
Dave Collishaw '79 S2 Daimler Sov '92 xj40
Peterborough, United Kingdom
In reply to a message from joe@joea.com sent Thu 13 Nov 2008:
Well I also think since I had #1 and #6 reversed and then I tried
to time the engine at 3000 rpm’s and obtain 14 deg BTDC.
Things can go horably wrong, like bent intake valves.
Now on to making her as smooth as she can possably be
Cheers
Michael–
The original message included these comments:
Agreed and my gut tells me that something else happened. Back-firing does
not bend valves, or at least not in the 40 years that I have been working on
engines of all types around the world.
Just my 2c worth but something else bent the valves IMHO…
In reply to a message from joe@joea.com sent Thu 13 Nov 2008:
I agree. Somehting else happened - likely off the engine such as
resting the head on the bench or turning the cams with the head on
the bench to set clearances but doing one while hte other cam was
still fitted. That could tangle valves and cause the three bent
valves this head had. I have never heard of anything bending valves
except brute force of contact between valve and piston or valve and
valve or valve and workbench. Bad timing does not bend valves, nor
does backfiring IMHO.
Pete–
The original message included these comments:
Agreed and my gut tells me that something else happened. Back-firing does
not bend valves, or at least not in the 40 years that I have been working on
engines of all types around the world.
Just my 2c worth but something else bent the valves IMHO…
In reply to a message from PeterCrespin sent Thu 13 Nov 2008:
Any chance that with a very loose upper timing chain there
could be interference if a backfire, etc. momentarily caused
the engine to rotate backwards?–
The original message included these comments:
valve or valve and workbench. Bad timing does not bend valves, nor
does backfiring IMHO.
In reply to a message from PeterCrespin sent Thu 13 Nov 2008:
Any chance that with a very loose upper timing chain there
could be interference if a backfire, etc. momentarily caused
the engine to rotate backwards?
May break a con-rod that, Bob - there is no reasonable way it will bend
valves. Arguably, taking up the chain slack as the engine starts
counter-rotating may ‘do something’ - particularely with excessive chain
slack, but the valve and piston movements will still be synchronised. It
may backfire for sure - but any odds that the backfire itself didn’t
cause bent valves…
Frank
xj6 85 Sov Europe (UK/NZ)>The original message included these comments:
valve or valve and workbench. Bad timing does not bend valves, nor
does backfiring IMHO.
In reply to a message from Robert Wilkinson sent Thu 13 Nov 2008:
I’m not sure you could have it loose enough and still assembled
correctly with all parts present? But I really don’t know. Food for
thought I guess.
Pete–
The original message included these comments:
Any chance that with a very loose upper timing chain there
could be interference if a backfire, etc. momentarily caused
the engine to rotate backwards?
