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MIDGET DOWN FOR THE COUNT......

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NardisCNC

NardisCNC

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OK.... since I have determined my fuel supply seems fine, let me start at the beginning with what happened:

Late last fall when the weather was still beautiful I was driving the backroads through Mammoth Cave Natl Park. Car was running fine, then all of a sudden I can around a curve, the car coughed, and started immediately running on what felt like 2 cylinders - no power, hardly running, had to keep my foot in the gas for it to do anything. I barely made it to the nearest town about 10 minutes away where I directed it to a parking lot where it did die, not to restart.

The previous owner said that one plug would occasionally foul, but after cleaning it the car would run fine. None of the plugs looked horrible but looked like they could stand to be replaced. I tried replacing all 4 plugs (gapped them first). The car did start and run for about 1 minute then died again, not to restart. Called the tow truck, got it home.

The rest of the ignition system did appear to maybe need the some maintenance, as the plug wires had a hole or two in them and were in very poor condition. So I went ahead and replaced the Dist Cap, Plug Wires, Points, Condenser, Coil, (using all the recommended parts by Jeff from Advance Distributor) Set the gap, and nothing... wouldn't fire. (this was on a colder night) A couple weeks later I went out and tried to start it again.... Fired right up!! Ran like a top, smooth as silk, for maybe 30-40 seconds then it died not to restart.

This is where we are currently. Once it a while it will start and run perfectly for a few seconds then die not to restart. And sometimes it won't even start at all, even after sitting.

Since it did fire and run smoothly few a short while a few times. Does this mean that the ignition is working and it is likely a carburetor (SU's) problem?? Or could the ignition still be at fault?

I will say also that the previous owner had the SU's overhauled and rebuilt in Nov '06 and they have probably only seen a couple thousand miles since then. I have the receipt, he spent almost 700 bucks too after parts and labor! Not to say he couldn't have gotten screwed, but they did work perfectly the thousand or so miles I have driven it since I got the car.

Thanks in advance!! The weather is very much here for driving this thing and I'm stuck!!
 
First I would check the float valves just to make sure they are not sticking and unsticking. Just make sure they are free.

Let us know and we will go from there.
 
I agree with Jack. You've tested that the pump is pumping, so reconnect it to the float bowls and try to start the engine. If it doesn't start, or starts and dies after a minute as you've been experiencing, take off the float bowl covers and see how much fuel is there. It's a quick check.
 
After you rule out all that, make sure you have spark when it quits.
Could be heat related, ignition switch, connectors, anything.
Fuel and spark.
 
TOC said:
After you rule out all that, make sure you have spark when it quits.
Could be heat related, ignition switch, connectors, anything.
Fuel and spark. [/quote

and air.

Doesn't sound like heat related as you can't get the car running that long.

Here's what I'd suggest.

1. Try to start the car on starter fluid - if it starts, then your first area to look is likely fuel. First check then would be flow (disconnect at carbs) the floats.

2. Then check spark - pull plug and see.

3. air - if you can get it running, cover the carb intakes partially and see if things get better.

keep us posted
Click to expand...
 
That *COULD* be some kind of intermittent pump failure problem. Basically, your pump works for a minute then dies. I am not sure which pump you have, but this kind of failure is not too uncommon on electric motors when the coil windings go bad. I have seen this kind of thing happen on a few other non-MG cars.
 
And that can be checked by looking in the float bowles, are they full when the engine quits.
 
Could be crap in one of the carbs. Time to pull them apart and blow out the passages with carb cleaner. Good thing to do anyways.

My FP started to fail intermittently. The points were worn so it would stop and so I would stop. I'd pound on the sheetmetal above the pump until I could hear it clicking and go. Replacement cured the problem. As Jack sez, if the bowls are dry, you now know why. But if the bowls are full carb cleaner is your tool.
 
Looks like everything is covered but I have one question. Carbs were built in '06, how long did it sit b/w runnings? YOu can take a brand new set of carbs out the box, run the car for 3 seconds, shut it down for 4 years and have to start all over again. ( not w/ new carbs, but "rebuild" the "old" ones.)
 
JPSmit said:
TOC said:
After you rule out all that, make sure you have spark when it quits.
Could be heat related, ignition switch, connectors, anything.
Fuel and spark. [/quote

and air.

Doesn't sound like heat related as you can't get the car running that long.
Click to expand...

Heat as in electrical switch or connection heat.
Current.
Bad "joint".
Heats up (electrically and opens), cools off, works.
Click to expand...
 
Here's a short anecdote:

A buddy at work has a BRAND NEW motor on his boat. Used it last season with no problems. This year he couldn't get it to run! He finally gave up and took it to the dealer where, after an $800 BILL :cryin: they informed him that GAS-AHOL was to blame. :pukeface: If it sits in the carb for ANY extended period of time, even a month or so, without running, the alcohol in the gas causes the rubber O-ring in the needle and seat of the float bowl to SWELL, thereby causing the floats to stick. Essentialy the dealer told him there is no solution and no cure except to run the carbs dry if it is going to sit for any period of time.

This did get me to think that the Grose Jets I used to see all the time might be a solution, but I don't know enough about them. I've never used them.

Anecdote #2 says, I have personally experienced intermittently working fuel pumps that caused similar symptoms as well. Whose to say that the Gasahol isn't affecting the fuel pumps as well. Boo! :wall:

JACK
 
[rant]Considering that practically all gas you get at the pump these days is gasahol, it's pretty infuriating that ANY manufacturer would use components that are not alcohol tolerant.[/rant]

BTW, the same thing happened to a boat my family owned when I was a kid.
 
Jack: I've been running gasahol is british cars for over 20 years and never had a problem.
Any shop that would tell your buddy that gasahol is the reason they are charging him $800!!!! are a bunch of crooks that your bud had best not go back to!!
It seems that anyplace that has'nt had experience with gasahol yet has now got something new to blame EVERYTHING on!


Like to give one more suggestion for the midget's problem. Coil. I once had a coil fail and drive me nuts with similiar symtoms. Check to see if your spark is nice bright white not sick yellowish blue. Should jump at least a quarter inch.
Good luck, Kurt.
 
Sure Enough!! ... It appears to be sticky float valves. The bowls were both empty. Removed the floats, cleaned both valves up, reassembled, fired right up and continued to run!!

This brings me to my second question. How common of a problem is this with SU's? It's seems very common based on the above responses. How can this problem be avoided?

And what about the Grose valves mentioned? Are they really an upgrade or are they subject to the same problems as the originals? Are they better quality? How are they different?

Ahhhh....... fixed one problem, found another (see new topic). Thanks for everyone's help!
 
It is a common prob in the last 10 years or so. Never happened in the old days.
 
Tomco had supllied kits with a disc valve years ago. I can't remember what it's called, but it worked well.
 
Looks like I need to place an order, while I'm at it, are the Grose Jets any better than the original float valves? Or should I stick with the originals?

Also going back to square one, where this problem started..... it felt like the engine was barely running on 2 cylinders. If one of the float valves sticks shut, it will cause that carb to stop working. And if I understand correctly, each carb feeds 2 cylinders? Will the engine run at all with only 1 of 2 SU's working? I'm just trying to figure out what went wrong at that point, because as mentioned I also replaced several ingnition components between now and then. I'm guessing it was probably a combination of both.
 
You'll get arguments all day about what float valves are best. My own limited experience says use the originals as I have had more problems with Grosse Jets. I can't explain why that might be.
As for running on one SU, you'll notice the intake manifold is a very large equalizer tube between the two. So all 4 cylinders draw on both carbs all the time although not equally. The front 2 get more from the front carb and the back 2 from the back. If one carb quits completely, all 4 cylinders get a weak mixture. The corresponding cylinders do suffer more than the others.
 
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