Oh wise and helpful listers...
I have a timing problem (thank goodness I'm not a comedian! Pa-dum-pum) on
my '77 1500 engine in my '74 Spit. To bring you up to where I'm at in the
process...
Acquired in August as a non-runner. Replaced the carb with a donor that I
rebuilt. Wouldn't start after rebuild. No spark at plug. Replaced the old
Lucas ignition box with a Pertronix LU-147 (my distributor is a Lucas
45DM4), so I now have spark at my plugs. I tried to start it (first time
since I tried when I got it last August - no luck) it coughed and sputtered,
and finally ran, kinda. It sounded like a one cylinder tractor,
putt-putt-putt - pow! - putt-putt-putt - you get the idea. I put a timing
light on it, and my mark was way below my TDC markers. I tried adjusting the
timing to bring the mark up into the TDC markers, and the engine began to
rev up and POW! - it backfired through the carb. In fact, while the engine
was putt-putting, I noticed that the carb seemed to be exhausting instead of
"in-taking." Checked the firing order, and learned that the current
configuration - 2134 -- doesn't match Haynes -- 1342. I left the Dist. Cap
connected to the spark plug cables when I changed out the pertronix, so I
have the po to thank for my headache. Tried the proper order to see if I
could improve the misfiring - nope. Wouldn't start at all, along with some
backfiring.
I removed the oil filler cap and rotated the crank pulley until I saw the
exhaust valve (#8) close and the intake (#7) begin to open, which is
supposedly top dead center for the #1 piston. My timing mark on the crank
pulley is at 0 deg. TDC. My Dist rotor was not near 11 or 12 o'clock for
firing sparkplug 1, so I removed the distributor and Drive dog, repositioned
the oil pump drive slot, reinserted the drive dog with the slot at the 12 to
6 position (as per Haynes Chapter 1 - Engine, Fig. 1.26, SEC 40),
repositioned the rotor to 12:00 and reinstalled the Distributor. Hooked
everything back up, turned her over and BAM! - (more severe than POW) -
backfired through the tail pipe. Re-checked everything - valves rock on #4
exhaust, then as the intake is opening - mark on pulley is about at 0
degrees. Rotor is about 12:00, heading for cap pin 1. I know timing is
supposed to be 10 deg. BTDC at 700-900 RPM, but geez, now I can't get the
thing to even start.
FWIW, turning the crank clock-wise by hand gets me an immediate reversal of
my rotor, so there doesn't appear to be any slack in the timing chain.
I know this is long, but figured more info would be beneficial in gaining
some recommendations as to what I've done wrong or what I could differently,
or what I need to do now (and I'm afraid I already know). Of course, I would
prefer not to break into the timing cover, if at all possible 'cause I know
it will be a PITA!
Thanks!
Greg Hendrix
Downingtown, PA
'74 Spitfire (STILL in traction and rejecting it's donor '77 engine!)
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