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MG MGB Technical - Slow to start

I have had my 1980 MGB around four years and the only way I can get car to start up in the mornings is to crank it for five seconds, wait a second and then kicj it over again. It normally starts up on this second crank if I release the starter amost immedilately after getting the engine turning.
Question is, why doesn't it just start up when I first crank it? I have rebuilt the 175 Z-carb and it passes the smog test with flying colors so the mixture is close to being right. Could the starter be loading down the spark somehow?
Looking for suggestions. Any one else have this problem?
Rick

Sounds as thought the ballast bypass wire is not in place.
George B.

Rick;
My 76B used to be difficult to start cold. I have since converted to dual su's with manual choke. I would crank, release, crank again, it would sometimes sputter and quit, then crank some more, when it would usually backfire, then start. Once started, it ran good, and would start again without trouble.I never did figure it out. It was like that for many years, I'm surprised I haven't had to replace the starter.

Pete Haburt
Pete Haburt

Are you allowing time for the pump to fill the float chamber? I know that on SUs, at least, parking up after a hot run can cause them to be pretty-well empty at the next start. If it were the ballast wire I would expect the same problem the second try as the first.
Paul Hunt

I've got the same problem with my '79. Once it's warmed up, it starts fine. Mine also passes smog with no problem here. I found it odd, since it runs like a champ and it idles just fine. I have yet to figure it out.
T Hughes

Paul,
Often an engine that has been warmed up, but is not hot, will turn over more easily; thus reducing starter drag and current draw. This allows more voltage to the coil and may explain the phenomena that others have experienced, even though their ballast bypass wires are installed.
George B.

Granted, George, but Ricks symptoms are with a cold engine in both cases.
Paul Hunt

After my last smog test in March, when starting in the morning, the first crank it fires and immediately dies. 2nd crank it starts up right away. In the afternoon for the drive home from work it starts on the first try. I'm thinking that the choke probably just needs an adjustment. I have the Zenith w/manual choke conversion. Other than that it seems to run nearly perfectly.

Cheers,
DGV '75 Tourer
Dan Vukmanich

I have the same problem - I've come to the conclusion that the car is reminding me how much or little attention it's been getting - one extra crank for each day of non-use.
Same-day starts - instant turnover.
Next morning - one crank then starts.
Sat under the cover since last weekend - 7 cranks before it catches, and some low-rev hesitation till it warms up.
Once warm, never stalls or runs rough.
Solution - drive every day! (yeah, sure ;-)
R. Martin Rogovein

First crank - fires: Air/fuel in intake manifold catches and engine fires a few times.

Engine dies since the float chamber levels have dropped over the intervening time. The fuel which has evaporated is hanging around in the inlet manifold and air filters, providing a combustible mixture.

Second crank - engine fires and runs: The float chambers are now full and the engine can run.

As Paul Hunt asked, are you giving the fuel pump time to refill the float chambers?

Mike
Mike

I wait till the fuel pump slow down to a slow click before trying to start it, so that is not the issue.
I'll check the ignition balast resistor bypass and make sure that it is working. I've tried many different chock settings but the problem always seems to be there with every setting.
Rick

The ballast bypass is really only needed under very adverse conditions, although it is possible that North American cars need it more than UK cars because of all their emissions mods, and as I say it is unlikely to be that given it starts at the 2nd crank a couple of seconds later. How long does it take to start if you just leave it cranking? Or doesn't it after, say, 20 secs?
Paul Hunt

Rick... the fuel pump stops altogether when your float chambers are full. If yours doesn't then perhaps you have a slightly dicky pump that's taking longer to fill your carbs?

The longest I've ever had my pump run (apart from after draining the carbs) was 4 clicks.

ttfn,
--
Olly
Oliver Stephenson

This thread was discussed between 06/06/2002 and 11/06/2002

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