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Triumph Spitfire - overheating
|My 1974 Spit starts fine and runs fine until it gets hot and then it starts backfiring and losing power. If I run it on a very cool day, I can run it for a long time, but when the weather gets warm, lookout! I've had it to the mechanic but all he did was put on some new hoses that were leaking. Any suggestions? Is this to do with radiator or oil cooling unit? Thanks for your help. As you can see, I'm not mechanically inclined.|
|How hot> Very Hot? Your radiator may be part blocked with sludge.|
Try cleaning out the radiator. This one is in all the books, but worthwhile. Best take the rad.out, but not essential.
Disconnect top and bottom water hoses. Fix up a hose pipe from a convenient tap to the bottom hose, and arrange for the top hose not to spray water all over the engine. (NB. Those push on and off connectors that hosepipes use are often just right to go inside the radiator hose and make an easy seal.) Turn on tap. Go and make a really hot cup of tea.
When you return, all that orange rusty stuff will have been washed out. Even better if you can take the rad. out, turn it upside down, give it a good shake with some water inside and flush it again with the hose. Even more rusty stuff comes out.
Re-connect hoses. REFILL COOLING SYSTEM (easily forgotten) Fill with at least 30% solution of antifreeze/summer coolant to protect the engine from more corrosion and sludge in the water. If you live in a warm climate, talk to your accessory shop about a corrosion inhibitor for the water - you'll be buying antifreeze but never mind.
Good luck. Please report back - it is nice to know if someone succeeds, and challenging if they don't.
This sounds like something I experienced long ago. Is the carb heat shield in place on your engine? Its a large flap-like gasket that goes in between the carbs and intake manifold. The object of this is to stop the carb bodies heating up and vapourising fuel before it gets to the jets. It protects the carbs from heat from the intake manifold and the exhaust below, which is why it looks like a flap. It took me ages to sort this out but when I eventually fitted the correct part the engine ran beautifully.
If your engine is overheating because of the cooling system being blocked I would expect it to cause a leak somewhere due to excessive pressure. You can tell this is happening because the engine will hiss (and you might see steam) when it is warmed up, then switched off.
Oh, another point : You can buy radiator cleaning fliuds from auto stores if hosing the radiator out doesn't work.
But check that heat shield first!
The other fellows may be right, but here's something else to check. Make sure it's in time. If the timing is off, the car will overheat after having been ran awhile. I am reminded of a time that my family bought a '26 Buick that was out of time. We tried to drive it home through the hills of Southern Indiana. Needless to say...it was an experience when it overheated.
|Check to see if you still have a waxstat type of jet on the carb. If you do that is your problem.....there are conversion kits available for the twin-carb European Spits. and I am sure that you can get one also. The stats get too hot and lean off the mixture too much. The heat shields mentioned above also help a lot and are absolutely vital if you stick with a waxstat|
|I am having a similar problem. I have new hoses, new radiator, new water pump, flushed the block, had it timed, and compression checked. It still overheats after running about 10 minutes in 80 degree temps. It's a 79 with an electric fan that brings the temp down, but it boils over when I turn the engine off. It has a single Stromburg carb. The car is brand new to me and in excellent condition. Help!|
|Bonnie you should have a US spec Spifire that has a single ZS carb. Check the fuel lines and see where they are routed. If they pass too close to the exhaust manifold the fuel can boil and cause the problem you discribed. |
|to bruce in ohio,|
my brother lives in LA and his did similar. i went to see him and when there i fitted a time delay relay to the fan circuit. this allows the fan to run on operated by the timer or the thermostat independantly of the car's ignition. make sure you allow for this in your car alarm's circuit as it will set it off all the time by causing a drain on the current. hope this helps.
This thread was discussed between 28/04/2000 and 21/08/2000
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