MGB & GT Forum

I was driving my 1972 MGB in nasty Atlanta traffic and sounded like it overheated and the engine cut out so I rolled into a parking lot. Waited a while and gave it another go. It started but didn't sound amazing. I tried to drive it again and I heard what sounded like an abnormally loud exhaust pop, then it lost power and cut off. I left it overnight and came back and it will turn over but no start. Then I flooded the carburetor with starter fluid and manually lifted the dampers (video attached) and it started and "ran" as long as the throttle was engaged. As soon as I took my foot off of the gas. It dies.

What is my problem? Did the overheating damage the fuel jets or an exhaust crack/leak? I replaced the spark plugs in case the hot engine block caused a misfire or a short ???

I'm going to have it towed back to my garage in the hopes that I can avoid paying a shop to get it running again. video: https://youtube.com/shorts/MkgnuyXsyqc?feature=share



Edited 1 time(s). Last edit at 2024-04-19 01:36 PM by doriantriga97.

Does the fuel pump work. I would disconnect the line at the carb and check for fuel flow. Could also be a loose distributor. I would start with basic troubleshooting techniques. Fuel, compression and proper spark. If you the first 2. Then test the coil and distributor. Did you check to make sure there is no water in the oil? That would mean a bad head gasket



Edited 1 time(s). Last edit at 2024-04-19 01:47 PM by ken472.

Thank you for the advice. How do I test the compression? The fuel pump is definitely working but I think you may be onto something because the fuel filter was completely full and it was not emptying/refilling when I was trying to start the car.

How do I test the distributor and the coil?

You need a compression tester for a compression test. I added to my previous post while you were posting. I mentioned a possible head gasket issue. An ohm meter can test the coil and wires. It is possible for the coil wire from the top of the coil to distributor to fail

Does fuel filter look dirty? Could also be a stuck needle valve in a carburetor

Depending on the ignition system you have it could be a bad condenser if you have points

If I test the spark plugs against the engine block would that rule out all of the ignition/distributor issues?

Did you watch the video I attached?

The video with all that starting fluid would sure a fuel supply issue. It looked like there is fuel in the fuel filter but not getting to the carb. Is it possible the fuel from the filter collapsed internally? I have seen that happen

In the video the fuel filter looked dirty. Sure you just don’t have an empty gas tank?

I don't understand. The fuel can collapse internally?

I filled up the gas tank before that drive.

Fuel line can collapse. Are you using ethanol free gas. Some older carb gaskets and lines don’t like ethanol

I've always only used 87.

I presume you mean with ethanol. I guess from the video I would first disconnect the fuel line before the filter and try to pump some fuel into a container. If there is sufficient fuel flow then I would change the fuel filter. It is possible that you got some bad gas also. The overheating issue is troubling. Either a bad thermostat or head gasket issue. Also could be a loose fan belt