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MG MGA - Nightmare in Downtown Miami - Carburation....

Well, today I took out my MGA for the first time, by the end of the drive I wanted to kick the damn thing! ;)

I had to take it to the DMV to get the title transferred and get the license plate.
So jumpstarted the car in the garage cos the battery is fairly dead (I killed it a couple of days ago starting it too many times). I took the car to the DMV and all went well. Got the title and plate. So far so good.
Then it started to rain, so I put the top up.
I jump started the car again in the parking lot, and drove it like 200meters until it started run badly, and starting to pop (like bad explosions), and within 3seconds it died -no further explosions (even pressing the gas it eventually slowed down more and more).
So we jumpstarted it again (by the way I can do this cos my dad was driving behind me in a regular car all the way).
In a distance of 1mile the car died 5 times including in my garage, with the associated aggravation of having to jump start the car in the rain, in the middle of the road, blocking traffic and annoying people behind us.

To get to my question; What do you think the problem is? What do you suggest I look for first?

I will give you the symptoms I am able to see.

- If you turn the ignition key on, the fuel pump ticks, if you leave it for more than a minute fuel will overflow out of the carb overflow tube.
Just reading on Barney's site that this is due to a 'sticky' float...(I will check this tonight)

- Is it possible that because the battery is dead, (and I don't think the generator is charging much), that the fuel pump is not running enough fuel to the carbs?

- At the beginning I thought is was an electrical problem (Remember Barney saying 'Most of carburetor problems are electrical!), but then I have noticed that if I rev the engine up to 5000rpm and then release to iddle it will die... I guess that fuel pump can't cope with the demand? Looking at the fuel filter (transparent type) usually it is 2/3 full of fuel, now when I looked at it was nearly empty.

- When I jump start the car it starts straight away and idles smooth at about 1300rpm

- I was also thinking that due to the rain and high humidity that could be affecting the distributor points?

So what do you think, fuel delivery issue or electrical?

Could the fuel pump be running bad?

Any ideas welcome!

G Ramos

Don't get too carried away just yet. You already know that you have a sticky float or two. resolve that issue first. It may just take a rap with the handle of a screwdriver to free it up. It may be dirt, in which case, clean it up and move on.

Second, you know that the battery is low charged. With a good electricl system, it will take several hours of running to get a battery fully charged from dead. And that is if there are no other electrical loads such as headlights or wipers. Or you can put a charger on it.

Get the carb overflow resolved and the battery fully charged before you go deeper. Running poorly is easily caused by either of the above issues. And you have both.

Humidity does not affect the points. However it will quickly show up a bad rotor, cap and/or wires.
Chuck Schaefer

the fact you say "- If you turn the ignition key on, the fuel pump ticks, if you leave it for more than a minute fuel will overflow out of the carb overflow tube" is a sure indication the float needle(s) are stuck open and that will cause exactly your symptoms. The pump MUST stop after a few seconds or you have trouble. Probably fine rust/dirt in the gas tank has been stirred up now that you are driving it (been there, done that). Fix that problem and do a test drive - I think you will find that is the only cause of the problem you are having.

By fix, I mean first clear out needles and get to the point you don't have the fuel pump keep clicking. Take a short drive, all should be well until more dirt gets in. Longer term is to put in a better fuel filter, and better yet, have the fuel tank cleaned and reasealed.

- Ken
Ken Doris

I'm going to go for that. Fix the float and also do a full change of wear items, including fuel filter, etc.

Thanks guys!
G Ramos

And check the points gap - should be 16 thou. You could drain the old gas from the tank - there is a "bung" in the bottom centre of the tank. Then fit a fuel filter - a convenient place is where the fuel pipe comes up just before the heater shelf.
You have just started to have fun!
Peter.
P. Tilbury

A similar thing happened to me - a seris of back fires and loss of power as I drove along. It was a loose low tension connection on the coil - efectively turning the car on and off as I drove along!
Good Luck.
Mike
Mike Ellsmore

Can't hurt a bit to put a can of fuel injector/fuel system cleaner in. I've taken to doing this on anything that has been sitting or infrequently used, and once a year on stuff that does get used regularly. Injected cars start to show signs of injector leakage, which is a result of varnish buildup in the nozzles; I figure carb cars have the same problem. Parts store will have a whole shelf of this stuff, from $2.59 to $20. I get the $6-8 stuff. Frequently helps starting, idle, flooding, etc.

FRM
Fletcher R Millmore

Gonzalo

My 10 pennywoth (cents) on MGA maintenance is to tackle one problem at a time. Otherwise, when the car is finally sorted you can never be certain what action fixed it, and this information can be useful for the next time.

As others have said, sort the overflow first. Most of us have suffered this during our MGA ownership. As Chuck says, it may be just a sticky float valve or dirt in it. The other high probability is that the float is holed and has sunk or is part submerged (quite common). If it is holed, it is easily repaired or replaced. Let us know and we will tell you how to repair it - it's a 10 minute job or so as long as you have a soldering iron.

Steve
Steve Gyles

Gonzalo

Kens's recommendation on cleaning the gas tank is something I would definately put on my list. Many years ago a good friend received a TR6 for his 16th B-day and for a little while it ran ok but it wasn't long till it kept quitting for lack of fuel. He had the fuel pump replaced, carburetors cleaned and it still had problems. One night we looked down in the gas tank and saw something so decided to remove it and see what was in there. You wouldn't believe what came out, several marbles, a really big spring, various small toys and lots of gunk. After we got it all back together it ran like a champ.

I had a MG midget and three of us guys use to climb in it all the time and head out on trips. It use to vapor lock quite a bit when it got hot out and would miss and carry on and stall. Once on I-75 it quit going up a steep hill so we turned it around facing down hill hoping the gas would drain down and it would start. LOL

The state policeman that stopped seeing a car on the side of the road facing the wrong direction wasnt too amused and was really perplexed that three boys were stuffed in this tiny 2 seater. LOL

Welcome to the world of classic MG's

Regards,
Rich
Richard Taylor

Well I cleaned both float chambers last night, and the floats seemed to be working fine.
I did not see the valved being blocked but I cleaned it anyway.
There was a considerable amount of brown particles in the end of the float chamber, so I cleaned that.

The pump stops ticking now and no overflow... (now I know for next time).

No looking at that I found I had other problems, like the choke mechanism on the carb had lost some if its nuts and washers... : ( Probably worked off loose.
I also found the conection between the float and the main body has a leak or is not sealing properly, so I am going to change now the rubber grommets.

I keep you posted on how it goes...!
G Ramos

Welcome to the world of old cars.
Im sure with all the help here you will soon understand your car and enjoy the experience.
DJ Lake

Gonzalo,

You started with the usual problems of the MGA, Carburators, you better buy the kit and replace it,adjust the float levels, (by the manual specs.)previously clean all the parts, install a gas filter as somebody suggested.
Electrical problem; check your battery may be too old or the charging system is not working properly.
R Garcia

As Richard and DJ say - welcome to old cars.
You are having the same sort of problems I had with mine 6 years ago. Just gradually work through all the carburation and replace seals/gaskets and also the ignition - new plugs, points, condensor etc. Short drives after each to check the effect and get more confident in driving further , getting used to the noises it makes . Watch out for the brakes as well - that's what scared me when the rear cylinder seals let go - check fluid levels every time you go out. Have fun - cheers Cam
Cam Cunningham

Last Christmas, my son gave me voltmeter that plugs into a cigarette lighter. If you have a lighter in the car, you can monitor the charging.
I think it was like $15 at Walmart.


Dennis Suski

This thread was discussed between 24/02/2010 and 26/02/2010

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