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MG MGB Technical - Water in fuel ??

I have recently been having intermittent trouble with my 67 mgb mk1. Every now and then, it will cough and fart, maybe run rough for a few seconds or a minute and then stop. I was convinced it was an electrical problem as it just seemed like the same thing you get when the distributor was wet (even though it wasn't).
I had my mechanic look at it and of course it wouldn't play up. He pulled the carbys off and said there was a lot of crap in them and said they could need rebuilding but wasn't certain that was the problem. He put new plugs and points in etc and the car seem to be running well...and then it stopped again a couple of days later, always in the most awkward spot too !
ANyway, I decided to bite the bullet and replaced the igintion coil, condenser, spark and coil leads, new distributor cap. Car was running better than it ever had and was pretty sure must have got the problem.
You guessed it, 3 or 4 days later it did it again.
This time when it stopped I dragged the choke out and it seem to perk it up a bit then die, which made me think it is a fuel problem somewhere. My Dad told me it sounds very much like water in the fuel. Usually when it has stopped in the past, if I leave it for an hour or two she starts again and everything ok for a while. Has anyone exerienced water in their fuel ? I certainly don't leave the car out or drive in the rain so if there is water it would only be condensation.
I have poured some stuff in the tank that is supposed to help if there is any moisture there and so far no problem. It is always in the back of my mind though that it will break down at a major intersection. (Is it just me or do people love seeing you push an MG and automatically assume that you are some smartarse showoff or something and serves you right)
The only other thing it could be is crap in the fuel tank or an intermittent problem with the fuel pump ?
I assume that if the carbys were that bad that they needed a rebuild ($600.00!) the problem would have gotten worse over time and it wouldn't be so intermittent.

Any advice or help appreciated
Craig

Craig - I don't know about water in the fuel, but your problem sounds like a clogged vent in the fuel tank cap. The next time the problem surfaces, quickly remove the cap and see if the problem goes away. If it does, drive for a while with the cap off of the filler neck. If the problem doesn't resurface, get a new cap. I will send you a fuel delivery troubleshooting guide tha may be of help to you. good lcuk - Dave
David DuBois

If they have SeaFoam or the equivalent carb cleaner there, run some through the carbs to clean them up. You drip it into carbs while car running.
J.T. Bamford

Water in the fuel will sit in the bottom of the float chambers and slosh about. So it will only get sucked into the carbs in a certain position, like on a right hand bend/left hand bend/uphill/downhill etc.
It's usually predictable, and that's what points to water in the fuel. If it doesn't fit this profile, look elsewhere although you may like to try some fuel system conditioner, made by people like STP which is supposed to absorb moisture.
Dave
Dave Wellings

Look at the tach when it starts coughing and farting. If that is flicking about or showing lower reves than you know it should then the problem is in the ignition LT. If the tach is still registering what it should the problem is in the ignition HT or fuel. Pulling the choke can 'cure' some ignition problems, but if it were fuel starvation it probably wouldn't make any difference.
Paul Hunt

This thread was discussed between 29/04/2004 and 30/04/2004

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