Running hot at idle
The cooling fan(s)
normally turn on at 195F (90C), so the idling temperature might get to
215F (100C) with the fan running. This is normal.
With 25% antifreeze and a 15psi cap, the boiling point of the
mixture is more than 235F. Temperatures that high won't damage an
|Antifreeze Mixture||Freezing Point|
general, antifreeze inhibits the heat transfer between the cooling
fluid and metals, so it's advantageous to minimize its percentage if
your engine is running hot. The addition of Red
Line Water Wetter to the
system is said to increase the cooling system efficiency too.
a "crankshaft power-pulley" which slows down the water pump will
aggravate overheating at idle. Instead, use a standard-diameter
pulley and/or a high-volume pump.
- Thermostat: A 175F-185F
temperature opening range is preferred. Using a lower opening
temperature will not
help if your idling temperature is higher than that. In either
case, the thermostat will be open the same amount. If the
temperature rises and falls periodically more than a few degrees, check
that the thermostat has a bypass hole as described here. If there is a hole, the
thermostat may be defective and should be replaced.
cap: 15-18psi is recommended.
in system: It's not unusual for air to accumulate in the intake
manifold by the thermostat area, causing local hotspots in the
cylinder head. You will get local boiling as a result.
Bleed from a intake manifold fitting, i.e. the temperature sender.
timing. Vacuum advance.
- Clear radiator fins
- Exhaust air from engine compartment
- Confirm that your gauge is reading
correctly first, especially if the car is not boiling over.
that you have flow in the system. With the radiator cap off and
the system over 200F, look in the expansion tank for flow.
that your fan is functioning. If it is not
Check the fuse
the plug connection
- Check that the fan is drawing air through
the radiator in the correct direction, not blowing toward the front.
hot at speed
- Collapsing lower hose. Make
sure that the long hose has an internal spring.
- Bad water pump
ignition timing, including sticking centrifigal advance.
- Clogged radiator.
Connection At Fan
the FIA harnesses made in late 2009, a manufacturing error may have
snuck through on some kits. Check that the colors of the ERA
harness and the
fan harness match.
the wires are reversed, they can be reconfigured by inserting a
small flat screwdriver (like a jeweler's screwdriver) into the plug end
and pry the tang back. The wire can then be pulled out of the
plug. Don't forget to pry the tang back out to the original
"catch" position when you re-insert the connection.