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MG MGB Technical - 79 MGB runs poorly

I'm new to MG's and am wondering where to begin. The car has not been run for about 1yr, and was not running until I put a new fuel pump on it last week. The fuel tank has been drained, lines are clear and filter is new. Idles fine. But, when I start out driving and then when I shift it sputters and has no acceleration for several seconds, then goes fairly OK.

I put in new plugs, wires, cap & rotor. The plugs are black/sooty, so I weakend the mixture some. Seems to not sputter so much, but still lacks any intial power. Also it seems to run a little worse as it gets hotter. I drove it about 20 miles yesterday and it was running worse when I finished than when I started. Also was idling fine at start, but idling fast at the end.

Thanks, for any help!
Glenn Lawrence

Check your ignition timing, and check for vacuum leaks. Also, check to see if your choke is working properly.
Jeff.

Jeff Schlemmer

Check the carb(s)- Zenith for a split diaphram and lack of oil in the dash pot, SUs for sticking pistons or lack of oil in the dash pot
Chris at www.octarine-services.fsnet.co.uk

Glenn. If still factory original, your 79 MGB has the Zenith-Stromberg substitute for a carburettor. Most of us have not been happy with them and have, over the years, replaced them with the earlier SU dual carbs or the two barrel Weber DGV series carb. There are several things to consider here. First, you state you drained the gas tank. Did you have it flushed out and cleaned? If not, you could have residue clogging the system. Did you have the carb cleaned and rebuilt? If not, varnish could be partially clogging some of the fuel passages or the jet. Since you are new to MGs, I would suggest you find a good mechanic to trouble shoot the car and find out what the problems are, then correct them. This website has some mechanic listings, by state and so do the North American MGB Register. The American MGB Association may also have some listings. You should also find the nearest MG club and join it immediately. Ask the members for recommendations as to whom they would go to. If you have the car tuned and put in good order, you can learn to work on it as the general problems come up. They are not difficult cars to work on, but the 75 on cars, with the Z-S carb and the extra emissions controls are more difficult to learn on than the earlier ones. As it sits right now, you only have the vaguest of ideas about what all the problems could be. Either find a competent professional or an advanced hobbiest to help you out. It will save a lot of frustration. Les
Les Bengtson

Thanks. I'm trying to find a mechanic who can work on this. Not to many in this area (northern PA), and the ones within a reasonable distance are extremely busy.
Glenn Lawrence

This thread was discussed between 17/09/2001 and 18/09/2001

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