View Full Version : Spitfire Spitfire losing power

05-31-2014, 04:59 PM
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?

05-31-2014, 05:05 PM
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.

05-31-2014, 05:49 PM
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

05-31-2014, 05:50 PM
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.

05-31-2014, 06:57 PM
Open the gas cap and see if the engine will pick up power.

05-31-2014, 09:08 PM
+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.

Andrew Mace
05-31-2014, 10:31 PM
Got a filter on the fuel line, Tom? Could be plugged?

06-01-2014, 07:33 PM
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.

06-02-2014, 07:32 PM
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.