1st start does not start until 4 or 5 turns!?

Hey guys, everything works and is fine except than $%*@^&# 1st start of the day in the morning. I have tried the 'one throttle press' start but no go, I must depress the throttle 2-4 times and then turn her over 3 or 4 time before it starts, especially on these cooler mornings. The rest of the day, one shot and it starts.
Plugs, wires, rotor and rotor cap is all new.
(on starting, rpms stay high 1500-2000 until I tap it, then drops and stays around 1100 rpms)
I'm guessing its fuel related not electrical, seems as though the carb is dirty or not holding enough fuel for those weekly early morn starts.
Appreciate any advice as always.

What kind of carburetor does your car have? Is the induction heater hooked up?

Kimberly Wrote:

The induction heater would have been on your original Stromberg, if you have two SUs then it is no longer needed.

mg1340 Wrote:

Keith,
As noted above orginal would have been a Stromberg NOT an SU.

If and how much is your fuel pump ticking before you crank the car? It should click for a short while then stop.

You must be talking about the 1 Stromberg carb., wich is what came with your 1980 MGB from the factory.

peace, Kyle

Englishcarlover Wrote:

Depressing the throttle 2-4 times doesn't have any effect on anything about an SU or ZS carburetor, neither of them have an accelerator pump. Turning over 3 or 4 times on a cold start is common and nothing to be concerned about. After all, we're dealing with carbureted cars with technologys at least 27 years old, not computer controlled FI injecting fuel right at the intake valves.

I always need to choke both of my cars on all but very hot days when starting the morning.

Choke issues.

Do you have a manual or automatic choke? If manual, depress the throttle and pull out the choke before you release the throttle, engine will crank over 4 to 5 times and start on fast idle. If automatic. follow the same process but the choke will set it self. Only press the throttle once! When you press the throttle mutiple times, you screw up the choke setting.

Fred

only four or five turns? not sure they started better than that when new. seems perfectly normal to me.

I've got dual SU's, but 4-5 turns on first start seems totally normal to me too.

Kieth,

Are you saying 4 - 5 engine revolutions, or 4 - 5 cranking "sessions"?

4 - 5 engine revolutions would be pretty normal. 4 - 5 different cranking "sessions" would be a little much.

Bryan

Bryanm362 Wrote:

in that case, it sounds like something is not quite right, probabaly with the auto choke, a problematic component, generally regarded as finicky at best. there are kits to convert to a manual choke, which may or may not violate your local emission requirements. depending on how any local emission tests are administered and if the tests rely on expertise/familiarity for any visual component, the emmision factor of a conversion may be a non-issue. the operation of the carb and actual emmisions would not be adversly affected.

First thing to check,IMHO, would be the air filter. My ZS would clog up if a grain of pollen got within a hundred yards of the car (the exhaust leak had nothing to do with it). What do the plugs look like? Another thing to check is that the three screws holding the water choke onto the carb are tight. If one has vibrated out then the choke would have difficulty operating. The good news is that the choke screws USUALLY fall into the frame.

Battery connections? For both my cars, when they begin to hard start even a little there's a larger problem looming. Starting at the battery and working to the sparkplug seems to be a plan that saves time for me. Amazing how many distributor problems start from a loose or corroded battery connection.

K.Mott
79 B HIF's, Pertronix, Jeff's rebuilt 45D, Z-car wheels
69 B GT Pertronix, 15" A wire wheels
Alternate daily drivers
OKC OK

LearningMGB Wrote:

What's the duration of your "cranking session?"

twentyover Wrote:

if you don't know where the screws are, time to consult or purchase and then consult a repair manual. bentleys or haynes. haynes also publishes one, or did, especially for the zs carb.