In reply to a message from iain6566 sent Fri 7 May 2010:
Hey Ireland,
Popping through the exhaust when in deceleration, could be an
indication of being a little lean in the mix. I had a simlar
problem and enrichened the mix a liitle. This reduced the tendency.
Good Luck!–
KenAshbrook, 1E77559 '67 2+2, '04 XJR,
Severna Park, MD, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from iain6566 sent Fri 7 May 2010:
My baffle collapsed and produced similar sypmtons for what it’s
worth.
Stewart
Auckland NZ
65 Roadster–
The original message included these comments:
meeting the other day. It had run gloriously on the way there, but
on the way back the exhaust was very ‘‘poppy’’ and it felt like the
engine was a bit choked (restricted). The only thing I had done
recently maintenance wise was top up the Dashpots with oil. Checked
–
Stewart65E
Auckland, New Zealand
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from KeithB sent Sun 9 May 2010:
All,
The more I have thought about it, the more it seems like fuel
starvation - Have done 2 tests - One directly from the delivery
side of the fuel pump and one at the far side of the filter in the
boot - both giving 2.5 Imp Pints in a minute (which is about 1 Imp
Gallon every 3 minutes). Pump is a Facet Silver Top - Part number
476087E. The web gives wildly different specs ranging from 18-36
GPH (pressure 4-5.5psi) but given that 2.5 Pints in a minute
equates to roughly 18 Gallons in an hour, I’m erring on the
conservative side. Given I have read in the archives that the V12
needs 30GPH (although can’t find anything to corroborate this in
the Parts Manuals or ROM), does the collective brain trust believe
my flow rate is too low and could be causing the popping and
restrictive power. I’m also going to check flow rate at the return
valve to see if there is a restriction between front and back of
car due to a flattened pipe or blockage (although everything looks
ok) but just wanted confirmation or denial that 18GPH is either
good, marginal or very bad!
Strange thing is that the car worked fine previously with good
acceleration, but I have improved and fixed a lot of
previous ‘‘repairs’’ so thinking this is just another ‘‘marginal’’ fix
that has been tipped over the edge.