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MGB 69 MGB sputtering problem

jimd

Senior Member
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Hi, After almost 10 years owning my car, and having it run great, this year it doesn't want to cooperate. It starts and idles great but lugs/sputters whenever I try to accelerate out on the road. Distributor is relatively new, new plugs, wires, coil. Carbs are immaculate. The only thing different this year from any other is that this past winter I rolled the car out of the garage in order to do some work in the garage and didn't get a chance to get the car back in (but it was covered). So the car was subjected to about 2 months of very cold weather - if that makes a difference. The only other thing is that if I take the vacuum hose off the carb that goes to the vacuum advance on the distributor and blow into it, there is no resistance and I hear air 'leaking' (the hose is in good shape). Also, if I take the hose off while the car is idling, there is no change in the engine idle. Does that mean the diaphragm (I'm assuming that is what's in it) is broken? Thanks for any help. Jim
 
If the car sat for several months without fuel stabilizer I would clean the carbs and maybe add some fresh fuel. Other than that I would change the condenser next. The vacuum advance issue will not make the car act as you describe. It may have been bad for a while and not noticed. With the car running suck on the hose and see it the idle increases and you get resistance. If you just suck with no resistance its time for a new vacuum unit. Good luck getting it back up and running good. Bob
 
If the car sat for several months without fuel stabilizer I would clean the carbs and maybe add some fresh fuel. Other than that I would change the condenser next. The vacuum advance issue will not make the car act as you describe. It may have been bad for a while and not noticed. With the car running suck on the hose and see it the idle increases and you get resistance. If you just suck with no resistance its time for a new vacuum unit. Good luck getting it back up and running good. Bob
I pump out old gas every year and put it in another car's full tank to burn up. Fill the MG with fresh gas. Carbs are clean. I ordered a new vacuum unit and when I install it I'll let you know if that works. I hope so. Thanks.
 
Sounds very much like you need to top up the oil in your carb dashpots. Over time, vacuum sucks it out.
 
Or fuel filter?
 
Ok, thanks for the ideas. I'll try them in the next days/weeks - very busy with other things going on. But I did get to spend some time on the problem yesterday - I installed the new vacuum advance unit, reinstalled the distributor and set the timing but still no luck (it might be slightly better).
 
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