I just obtained a 1971 Jaguar 12 cylinder with manual transimission. The car was stored for many years before I obtained it. I do not beleive that the car was prepared properly for long term storage.The problem that I am experiencing is that after the first 5 miles of driving, suddenly the Amp meter starts to go into the red, the oil gauge also drops. The engine begins to run rough and the idle drops off when the car is stopped and the engine dies out.The engine readily restarts. The next day after the engine has cooled down, the engine again runs fine for the first 5 miles and the the process repeats itself. The engine is NOT running hot.
Anyone have any ideas?

 

Hi Joels,
Its likely the Amp and Oil pressure readings are due to the engine starting to stall. The Stromberg Carburetors would be a good place to start looking at first. There are two compensator, heat and overrun, that can stick, and or leak that will cause the engine to run really rough. The Overrun Compensator has a diaphragm that would likely have lost its flexibility over the period you speak of. They also develop splits when they harden up.

After such a period of inactivity, it would be good form to have the carburetors serviced. There's a small "O" ring on the screw at the bottom of the Dash Pot, used to adjust the metering needle, that goes out of shape and becomes very brittle. This then allows oil from the Dash Pot to leak out. This fault won't cause the problem you're experiencing, but its a good idea to replace these, as low, or no oil in the Dash Pot will result in poor immediate response to acceleration. The damping of the air slide by the oil results in the fuel/air mixture becoming momentarily richer for quicker acceleration.

Regards,

Bill

 

Thanks Bill,
I will try your suggestions.

 

How did you make out on the tune up and is she running better?

jake