Go back to the basics, and don't assume anything without checking:
1: Spark - Yes/no and when.
Pull a spark plug lead, hold it with insulated pliers about 1/4" away
from ground, have someone crank the engine over. Nice blue-white
spark? Good. Go to Fuel No? Something's not right in ignition,
possibly the points installation. (The Voice of Experience: I've driven
myself crazy trying to diagnose a bum ignition system that turned out to
be that I'd put the terminals and insulators back on in the wrong order
when I put the new points in. Argggggh!)
Slap a timing light on #1 and check the timing one more time while it's
cranking over. Close enough? Go to Fuel. Whoops? Fix it.
2: Fuel - Too little or too much. (I'm assuming that you have SUs on
there...)
Try using more/less/no/full choke. Play with the choke knob and see if
you get closer to starting. A freshly redone head may have changed
things enough that you need to use a different choke setting. If it
come s closer with no choke, you may be way too rich now.
Turn the key (just to "Run" not "Start") and listen for the fuel pump
ticking. No tick? Fuel pump quit or total blockage in fuel lines.
Ticking? Go to next check.
Smell/look for gas running out of carbs. Outside of float bowls wet
with gas? TURN KEY OFF Float needle staying open/too much gas.
Everything dry? Go to next step.
Crank it over and smell for gas. If it isn't firing, you should smell a
little gas. Open the top of the float bowls. Dry or float low in
bowl? Float needle sticking shut or blockage in fuel lines. Float bowl
full/reasonably so? Go to Compression.
3: Compression
Yeah I know, you've got a new cylinder head on there, but go ahead and
pull the plugs and do a compression test anyway. While you've got the
plugs out, look at them. Anything look/smell odd? If it isn't Aces
here, get on the phone to the shop that did the head and start
inquiring. If it ran going in, and all they did was the head, and it
only ran for the trip home, I'd suspect maybe something's amiss in their
work, particularly if the plugs seem wet with water (rather than gas).
If you can't get it to start following this, you should at least get
clues that will take you to the correct solution.
Hope this helps...
Chris K.
DuhCaddyhm wrote:
>
> Hi All !!
> I'm new to the list, but have actually been here for a while. Lots of
> great info and fun. Now I need a bit of "MG expertise"!
>
> Problem: '74 Midget. Won't start. Turns over and acts like it's
> trying, but just hasn't enough oomph. Had the head done, drove it home
> (four blocks) and hasn't started since. Here's what I've already
> done/checked ..... what's next???
>
> New plugs, gapped right (second set); new plug wires, all correctly
> aligned on the distrib cap. Starter replaced, works great. Battery
> new, fully charged, new cables, clean terminals, connections good.
> Coil, CB points, condenser all replaced (seem to be okay), gaps and
> connections good, current at the points and coil is good. Rechecked and
> reset the valve clearances. Pulled the distrib and realigned the drive
> dog correctly (it was out about a notch). Just for grins and giggles I
> replaced the radiator and put in a new stereo and speakers, thinking it
> would make sooth the beast .. no such luck.
>
> So where do I go from here??? Thanks for the help!
>
> Sue, northern California (which is also bigger than Wales)
> '74 Midget
> '65 Midget
> '65 MG-1100
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