To recap: My 145 turns over and nearly catches but doesn't. I have a nice blue spark (thanks for the previous tips, guys), a 5-month-old ignition set and lots of air. That leaves fuel -- a one way trip to SU HS6 City. And I live in mortal fear of carburetors.

Here's the status: The choke cable is connected only to the rear unit. I've never had a lick of trouble starting it, but it does need the choke on for some time until it warms up well. The car has been idling high, 1500 ish, and running somewhat rich, to judge by the carbonized spark plugs. But there haven't been any power or running problems that I've noticed.

Tonight, fuel overflowed from the rear float chamber as my (long-suffering) wife cranked the car. I don't know whether that's a regular occurence or just something that happens the fourth or fifth time the engine is cranked without success.

What's the procedure now?

Thanks in advance,

Steve M.

Yea...where are you? I too only have the rear choke hooked up on my car, and it usually starts fine, but I have to manually choke the front carb if its super cold (below zero).

Also...sounds like you *might* only be getting fuel to one carb. Easy enough to pull the float covers and see if there is gas in both chambers.

Where did you last buy your gas? Was it a reputable brand name? The slightest amount contaminant or impurity will leave you dead in the water so to speak. Pull the fuel line and stick it into a clear bottle and pump a little gas into that... water will sink to the bottom. Therefore, a half cup of water in the bottom of your tank can cause a no-start issue right off.

You can also probably see the separation in the float chambers themselves if there is any.

Have you tried starting fluid at all? Could your distributor timing have slipped?

-Matt

You should not get carb overflow on cranking. Sounds like you are
flooded. If it is really cold you might also have ice in the bottom
of one or both carbs. I think I would pull both float lids and see
if the level is equal or not, should be about half or 2/3 full.
If one is quite a bit higher than the other, check how the floats
are set. If they are set the same, you definitely have a float valve
problem.
If you have the mechanical fuel pump on the side of the block, you
probably don't have a fuel pressure problem, but if you are using
an electric pump that is a distinct possibility. SUs don't tolerate
fuel pressure much over 3 psi. My experience with fuel pressure regulators
has not been good -
--
George Downs, The "original" Walrus3, Bartlesville, Oklahoma

I missed any previous chapters, but have suffered through some of the SU Blues in way-past years. Got oil in the pistons? How cold is it where you are? I am a firm believer in lightweight oil in cold weather. Much under 32F I'd recommend ATF. Also, if it is cold, you might need choke on both carbs...