Triumph Repair: engine overheating, spitfire 1500, radiator system

Question
Thank you for your time. I live in Indianapolis, In. I have a 1979 Spitfire 1500.  My problem is my engine is running at aprx. 205 degrees. It runs very rough.  I currently have my timing at 8 degrees. I know that I should be at 2 degrees ATDC but it seems to run the smoothest at 8. (At 2 degrees the car backfires quite a bit). I put in a new block, pistons, and crank. I am using my old valves as well as my old coil (will replacing my coil help?) and balase resister. After my engine starts the balase resister reduces the voltage down to 8.3 volts. If possible, can you give me a list of things I should do to lower the engine temp. (Which I see as my most urgent problem), as well as make the car run smoother. Thank you for your time. I live in Indianapolis, In. I have a 1979 Spitfire 1500.  My problem is my engine is running at aprx. 205 degrees. It runs very rough.  I currently have my timing at 8 degrees. I know that I should be at 2 degrees ATDC but it seems to run the smoothest at 8. (At 2 degrees the car backfires quite a bit). I put in a new block, pistons, and crank. I am using my old valves as well as my old coil (will replacing my coil help?) and balase resister. After my engine starts the balase resister reduces the voltage down to 8.3 volts. If possible, can you give me a list of things I should do to lower the engine temp. (Which I see as my most urgent problem), as well as make the car run smoother.  

Answer
Drew,

About engine temp:  

The engine is a heat "source"... and the radiator system is the heat "sink"...

If you're running hot.. either the engine is making too much heat, or the radiator system heat dissipation capacity is diminished for some reason.

Ok... let's look at the engine.  The engine will run cool when the combination of fuel mixture and timing advance are within certain limits.  

Let me ask this;  how are you measuring the ignition advance?  Timing light?  

If you're having to retard the timing to get the car to run smoothly, it suggests that the carb might be out of adjustment.  

How do the spark plugs look?  Dark, as if the car is running rich?  Bright white, like it's too lean?

Are you still running the original electronic distributor system (Lucas 45DE4)?  An earlier distributor?  Or an aftermarket unit (Crane/Pertronix/??)


As to the cooling system:

1)  What thermostat is installed?
2)  have you verified that the thermostat is operating (either in the car or in a pot of boiling water on the stove).
3)  Is the electric fan operating?  Is it pulling air in the correct direction?  (DC motors will run in reverse if the leads get swapped).

That's a start.  If you want a good source of troubleshooting information, try to track down a Bentley Manual for the late Spitfire (published by the Robert
Bentley Publishing Company, Cambridge Mass.).  The Bentley manuals have the complete reprint of the factory manual with good troubleshooting tips.

I hope this gets you aimed in the right direction.  If you need any more help, feel free to drop me a line.


Cheers,

Jim