...is my Spit running on only two cylinders?
I have only been pootling around town in the Spitfire during recent
weeks, and I have not noticed any significant loss of power, but I have
noticed a slight tendency to roughness/unevenness at low revs. Today I
decided to check the plugs (they were fine, all the same perfect biscuit
colour that is shown in the manuals), and to treat Carly to a new set of
HT leads, as the old ones have been in for a few years, and I couldn't
think of anything else constructive to do!
After I had fitted the new leads, and fired up the engine, I remembered
that I had intended to spray contact cleaner on the contacts on the
dizzy. Without turning the engine off, I pulled No. 4 lead, and was
astonished to find that it made no difference to the engine revs or
smoothness. Then I replaced it, and pulled No. 3. Same thing
happened. When I replaced that and pulled No's 2 and 1, I got the
result I expected: the engine stuttered and died in each instance. I
then tried pulling both No's 3 and 4 leads simultaneously. That didn't
make any difference to the engine note either. I checked the spark,
and all four plugs are sparking beautifully. Any suggestions? The
only thing I can think of is that some kind soul has recently detuned
the rear carb to such an extent that there is no fuel getting to the
rear two cylinders! Not so fanciful as it sounds. As long-term
readers will know, Carly has been the subject of some pretty inventive
vandalism over the past two or three years. Back before Christmas, I
found that someone had lifted the bonnet overnight, and removed the nuts
from the exhaust manifold downpipe studs. Yesterday morning, I found a
Christmas tree on her roof...
I shall be checking the tuning tomorrow, but if you have any other ideas
or suggestions, I'd be delighted to hear them.
Any and all help gratefully received.
ATB
--
Mike
Ellie - 1963 White Herald 1200 Convertible GA125624 CV
Connie - 1968 Conifer Herald 1200 Saloon GA237511 DL
Carly - 1977 Inca Yellow Spitfire 1500 FH105671
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