Slight engine hesitation

[pankeyg]

I really would appreciate some help with figuring out what is causing my 1978 MG Midget to hesitate during acceleration.

Here is the deal. I reclaimed this car from my father's garage last summer. I originally had the car while in college. Upon graduation, I moved east (Boston area) and left the car in Ohio. 20 years later I'm making the car a hobby. The car sat idle for most of the 20 years so I've had to get a lot done on it.

New Weber carb - converted from ZS because I thought the ZS was the issue. The Weber carb is far better as it has corrected choke problems, idle issues, and I no longer smell gas while driving. Also, the car is performing far better. It has some pep.

Fuel pump - original but good working order, at least it appears to be fine.

Thanks for any help or suggestions.

 

[SilentUnicorn]

Good Morning Gary,
here is a link from Mr Barnhill's site https://theautoist.com/weber_carb.htm
you may find it helpful. Have you checked your fuel tank and filter for crud from sitting? i have the same set up as you do, except i have desmogged my engine. I have been fairly happy with the webber, it does however on spirited occasions have a mild stumble as well. I am living with it until i can get my su's mounted.

where abouts in NH are you located? I am in Rutland VT

mark

 

[pankeyg]

Thanks. I'm in Rochester, NH.

 

[DrEntropy]

Mark, Is Burlington in your travels? There used to be a nice pub there called "P.T. Meguire's" (not sure of the spelling). Just wondered if it was still around. /ubbthreads/images/graemlins/cheers.gif

 

[lesingepsycho]

I have a weber currently on my MG and it hesitates as well. In all of my research and speaking with people, it is simply a problem inherent to these setups and there is no way (that i have ever found) to rid the problem.

The only true way to get better performance is to revert back to a pair of WELL-REBUILT SU's. And when I say well-rebuilt I mean it. The biggest problem with SU's is having a set that isn't perfectly matched. I spent about 40 hours, yes that's four-zero, fourty hours rebuilding a set of SU's (lots of wire brushing, toothbrushing, cleaner, polishing etc) and they definitely out-perfom a weber now. The best part is that I only spent about $120 for the rebuild parts and then I sold the weber on ebay for far more than that! Better performance and money in return, how can you beat that!

JACK

 

[SilentUnicorn]

Doc, Burlington is two hours north of me. Never heard of the place but there are quite a few places up there i have never heard of.


A pair of su/s is where i am heading, they are on the bench and patiently waiting for my time.


mark

 

[pankeyg]

Hi Mark.

Mr. Barnhill's site has helped. The recommendation about turning out the idle screw 1/8th to a quarter revoulution produced noticeable results. Now there is no hesitation when the carb gets the gas.

There were other recommendations like changing the fuel filter and fuel tank. I'll check the filter first. I don't doubt the tank requires cleaning. I'm going to have to wait a month before I get to this.

Question: I have never used gas treatment products like STP. Is it a good idea to use these products and if so, what kind of treatment schedule should I follow?

 

[SilentUnicorn]

Gary, i dont use gas treatments myself, well occasionlly some drygas, so i cant be much help there. I would read the bottle directions on your chosen brand, cant see where it could hurt and it may help.
The thoughts about the gas tank where that maybe you could have drawn some crud up into your carb, causing some issues. glad to hear the link was of some use.

mark