To quote an old Jazz tune, 'Everything happens to me' - well at least
this week.
Got home, keen as mustard with a plan in my head.
1) Adjusted the tappets spot on to .38mm
2) Took a look at the dizzy, about 2-3mm of vertical movement and .5mm
side-side/up-down movement. Doesn't feel *too* worn, but don't know what
it should be vertically.
3) Readjusted the carbs to start, 1 1/2 turns idle, 12 flats down on the
jet. Actuated choke and started the car till warm. Lumpy idle but not
too bad with choke out, jets down - a bit.
4) Disconnected vacumn advance from dizzy and blocked line to carb.
5) Checked timing, unbelievable - 20 degrees BTDC. How I don't know.
Didn't adjust the dizzy. 20 degrees is std for my car.
6) Disconnected linkage, balanced carbs and set idle to 900rpm per
manual.
7) Enrichened mixture on each carb by the same amount to attain fastest
idle (approx 16 flats, 1600rpm), readjusted the idle screws - perfect
idle!
8) Tuned the carbs individually by listening to exhaust note, colour of
exhaust and lifting the piston slightly with a screwdriver to check for
lean mixture,rich mixture per Lawries video and the Haynes SU Manual.
9) After that idle sped up slightly maybe 300rpm so I reduced the idle
screws a bit to get my 900rpm idle back.
10) Gave it a rev or three and all appeared fine.
11) Went out for a run, bit sluggish and occasional very very slight
misfire (sounded over rich to me) coming off throttle. I leaned the
mixture maybe 1-2 flats and big improvement in performance, no misfire
at all. Sounded smooth as a babies bum - or so I thought.
So you remember Titantic? The greatest disaster movie ever? Well like
South Park someone should have had the video on me - ie Kenny and not
Cartman. Well here I am spinning along at 4000rpm in second when there's
a funny noise, like a rattle, and then a clonk, clonk, clonk, clonk in
time with the motor. If I could swear here, safe to say it's a four
letter word beginning with F. Got it home as was only around the corner.
Listened to her there for about 20 seconds and it sounds like something
is inside the cylinder whacking around - but it is really hard to tell
where the noise is coming from. I took the carbs off to see if my crap
work had made one of the throttle discs disappear down the intake
manifold (paranoia) - nope. The dizzy appears ok, too hot to remove to
check the bit at the bottom. Took the tappet cover off, tappet all there
- fine. Took the plugs out and did a compression test. 1-4
156,154,128,153. Put a bit of oil in the third cylinder and wham up it
goes to 155.
Whats happened? Have I lost a ring? Did detonation cause this - my carb
tuning - or just coincidence? Not a valve is it as the oil is causing
the compression to go up. Something else? The engine appears to be quite
difficult to turn over by hand now. Is that because it's warm or
something to do with the clattering?
Bet you can hear me crying from here. Just when I thought I had this
right. OK I was giving it 'a bit of a roost' (revving it), but heck I've
revved it a hell of a lot more than that in the past. I didn't go over
4500 anyways.
I want to go hide now. I'd grin, but this aint funny. I guess I should
have just de-enlisted in shame, but stuff it I'll stick around. ;)
Neil.
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