I have seen some people relocate coil to cool side of engine bay using much longer HT lead.
General Still not working (hot running)
- Thread starter hodgy18
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General Still not working (hot running)
Can you increase a lack of voltage?
Just kidding.
HT leads are designed to transmit the electrical energy so can't think it would cause a problem, the 500 isn't a giant car.
Why not give it a try.
It was also suggested that condensers can fail when hot . did you treat your 500 to a new quality condenser when you fitted new coil?
If you have a new coil and it's not faulty, I don't think you will solve anything by re-designing the air-flow. There's something else going on. If following the coil route for a solution it is worth checking what the generator output is, as it may be kicking out too much voltage and overstressing the coil.
There are many other possible reasons why your engine is misbehaving in that way. I'm presuming that you have done a search on this forum keyword "overheating"?
There are many other possible reasons why your engine is misbehaving in that way. I'm presuming that you have done a search on this forum keyword "overheating"?
People haven't relocated the coil to the left side of the engine. That's where early F's and D's had their coils. Not sure why Fiat decided why to move it to the hottest part of the engine bay, it seems a rather daft thing to do. The only logical reason, is as you say, that you are going to get a higher voltage drop the longer the HT lead. Any piece of wire has a resistance and that increases with its length.
My 1966 500F has a coil on the left and I don't recall ever having any problems with it. I have just upgraded it when I changed to electronic ignition.
As Peter says you probably have other issues causing it to overheat, the main one as he says it's to check the LT voltage and make sure it isn't too high and causing the coil insulation to breakdown. The original coil probably cooked itself for a reason, which if you do not find it first, you are just be going around in a perpetual circle of spending money on coils.
Tony
My 1966 500F has a coil on the left and I don't recall ever having any problems with it. I have just upgraded it when I changed to electronic ignition.
As Peter says you probably have other issues causing it to overheat, the main one as he says it's to check the LT voltage and make sure it isn't too high and causing the coil insulation to breakdown. The original coil probably cooked itself for a reason, which if you do not find it first, you are just be going around in a perpetual circle of spending money on coils.
Tony
A sensible max is 14.5 v
As alternators should limit at 14.8v
If your voltage regulator is already below this and keeps your battery charged don't adjust it as it's working well.
On a slight aside don't get a calcium battery if you have a dynamo. calcium batteries require a higher voltage than normal batteries to charge properly, they die very quickly if not charged by a voltage over 13.8v .
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One possible reason for relocating the coil is to reduce radio interference, either directly because a longer lead radiates more or they changed to a resistance type lead. The resistance of a copper lead will make virtually no difference to the spark in an ignition lead because it's high voltage / low current (That's why power transmission lines are very high voltage).
Another cause of coil heating is excessive dwell time (contacts closed time). If the contacts are closed too long the inductance of the coil saturates and excessive current flows causing heating. Wrong dwell time can be caused by points adjustment, worn distributor cam lobes, worn pints slipper that runs on the cam or pitted points. A new set of points may be a good idea. You can measure the dwell time with an automotive multimeter or an oscilloscope.
Robert G8RPI.
