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Spitfire Spitfire losing power

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tomgt6

Jedi Warrior
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I have a mk 3 early 1300 spitfire engine.
It starts great, runs great for about 10 miles and then starts to lose power.

If I give it more pedal I don't get any more power, feather the pedal and no more power.

What should I be looking at? or what do you think could be causing the issue?
 
Well, just off the top of my head, I'd think the fuel pump may be failing. Can't keep the bowls filled.

Could also be a failing ignition condenser and/or coil. As they heat up, the spark gets weaker.

My two cents.
Tom
 
Make sure you don't have a suction leak in the fuel line before the pump! At idle it'll fill the carbs, but on acceleration, not enough fuel will be supplied. I wonder how I know that! A shielded flex line on our car had a very small crack in the rubber and the car did exactly the same thing as yours. It would run great for a couple miles and then slowly die. PJ
 
Tom I had that happen on a 65 Spit that I used to own. It started just after I filled the gas tank. It turned out to be a bad batch of gas that had water or something in it. After trying about everything I could think of I ended up removing the gas tank and flushing it out. That took care of the problem.
 
Open the gas cap and see if the engine will pick up power.
 
+1 on opening the gas filler cap as a test.

Also, when this power loss starts, what is the tachometer doing?

EDIT: Nevermind the tach. I forgot you said this is a Mk3 and therefore it will have a cable driven tach. I was thinking of the later cars with electronic tachs. You can see symptoms of some ignition related problems in the behavior of an electronic tach.
 
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I'd go the fuel, condenser, coil route. I had a similar problem a couple of years ago with a MKIV. Turned out to be the condenser. Good luck.
 
Here is what I have tried:

1. Fuel filter and gas cap open (mk 1 gas tank)
2. Switched out fuel pump
3. Traded coil out for another one

I guess the next item I will try is the condenser. Thanks for the help.
 
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