Have you checked the ignition timing? I had the exact same problem,
where the car was getting great spark & fuel, and would even run fine...
when the car got started. However, some days she just wouldn't start.
:( The problem was my ignition timing was too advanced (like 25 degrees
BTDC). What would happen was the spark plugs would be firing while the
pistons were still well on their way up (desirable to a certain degree
at high RPM's, but not desirable while starting), causing the engine to
turn over more slowly and made it near-impossible to start sometimes,
esp. on cold days. This, I hear, is a classic problem, but it took me
many days of frustration to figure it out. Once I retarded the ignition
to 10 degrees BTDC though (as per Haynes manual, which differed in its
recommendation from the '69 MGB manual which said 20 degrees?), my 'B
always has easily started on the first try. (In fact, after making this
timing adjustment and despite driving her almost daily for ~800
miles/month, I've had to do NO WORK on my MG for this entire calendar
year except for swapping out a front U-joint and changing the oil...
easily a record for my B! :))
I'd suggest checking the timing via the static method, or if there's
another person around, use a timing gun while the other person cranks
over the engine.
-Felix
'69 MGB
'00 Z3
both at http://felixwong.com
> Thanks for the suggestions. I had already checked for spark at the
> plugs ... all good. Plug wires are lined up properly on the cap, with
> #1 at TDC, and the rotor pointing to #1 plug wire. Elec fuel pump works
> great, fuel getting to carbs without problems. Points set with correct
> gap and spark there. Realigned the distrib and drive with timing marks
> set and #1 at TDC ... was off by a click, but is correct now.
>
> Still wants to start, but isn't ..... will recheck for spark and
> replace the rotor button this morning and see what happens. Will also
> check the earth strap .... hadn't done that yet.
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