Aside Chris Petris
Illustration by Chris Petris
A familiar question asked among C4 Corvette owners is "why does my engine run so hot? The cooling fans manage not come on until the coolant temperature is way too tasty".
Federal regulations required high operating temperatures to keep back idle emissions at their designated levels. The O sensor works more efficiently at high exhaust temperatures promoting less fuel usage and emissions. For this reason, we recommend victimization a borderline 180 degree thermostat and turning connected the chilling fans at the 200-205 degree range. 1984 Corvettes leave have the most noticeable improvement, every bit the factory cooling system rooter setting is 238 degrees. Lower temperatures bequeath work at the expense of fire mileage.
There are various cooling fan control switches ready to turn the temperature reduction fans on earlier than the manufactory ECM OR PCM controlled settings. We recommend victimisation a temperature reduction fan switch that matches the thermoregulator hatchway temperature. E.g., our 244455 sports fan switch turns the fan happening in the 200 level ramble. When the engine coolant temperature drops below 185 degrees, the cooling sports fan is turned off. Installing our 243108 thermostat allows the locomotive to run in the 185-192 degree range. Preceptor't forget the 242135 thermoregulator gasket to properly seal the thermostat caparison.
Some other scenario would be the use of a 195 degree thermoregulator with the 244455 switch. The fan would lam almost constantly as the thermostat regulates the temperature at 195 degrees.
For depress operational temperatures, our 243139 Hyper-Technical school Power Stat coupled with our 244381 cooling rooter electrical switch (that activates the fan at 185 degrees) would provide the slump hysteresis.
Have a Corvette that sees track time on a regular basis? Our 244502 (1984-93) or 244503 (1994-95) manually operated interchange allows you to override the automatic switch for additional chilling while wait in the theatrical production area.
"Why not escape the cooling fans continuously?"
Radiator cooling fans were not designed for continuous use and they bequeath give way untimely.
INSTALLATION NOTES
All of the aftermarket cooling fan switches have harnesses provided to connect the new style connector.
GM had a B4P chilling organization option available for 1985-1989 Corvettes. This option consisted of an extra chilling devotee in foremost of the a/c capacitor, cloggy duty radiator and oil cooler. We have had both the laborious duty and standard duty radiators out of the 1985-89 models and could not see any major differences. 1990+ Corvettes give birth two radiator chilling fans. 1990-1991 Corvettes also may take in an oil cooler. 1992-1996 Corvettes do not induce oil coolers due to clearance issues when the catalytic converters were moved close to the oil filter.
1990-1995 Corvettes will have a quadriceps femoris number one wood code set (16). The code will be seen piece using a computer electronic scanner but will not turn happening the SES light. This code will not will not affect railway locomotive functioning in whatsoever way.
1996 Corvettes will have an SES fatless illuminate when the sports fan switch is installed imputable the PCM noticing the winnow operating when IT should non be. This will non touch on locomotive operation or cause any problem.
1984 COOLING FAN Change over Initiation
The 1984 Corvette has a standalone cooling sports fan control circuit. The switch is connected directly to the cooling system fan relay without whatsoever railway locomotive reckoner intervention. The cooling buff switch is located in the rider face cylinder channelize betwixt cylinders number six and viii spark plugs. Use up the supplied harness to connect the brand-new style connector to the fan switch.
1985-1989 COOLING FAN Interchange INSTALLATION
1985-1989 AUXILIARY FAN WIRING Instruction manual
1990-1996 COOLANT FAN SWITCH INSTALLATION
1985-1996 Corvette Low-down Temp Cooling Fan Control Replacement would be installed therein location (driver's sidelong cylinder maneuver between cylinders 1 and 3).
Wiring Operating instructions:
1985-1989 B4P Option equipped Corvettes
Cut the dark green /white wire at the inner pilot well. Connect one of the new rule wires to the dark green/white wire. Route the other harness telegram to the main rooter relay (near the battery). Locate the dark green/white wire at the relay connecter. This will make some cooling fans come on simultaneously, import to a lesser extent lam time for some fans if the engine cooling system is in genuine condition.
1985-1989 Non B4P Optioned Corvettes
Route the cooling rooter harness dark green OR blue wire to the main fan relay (near the shelling). Locate the dark green/Edward Douglas White Jr striped telegraph at the relay connector. Splice the new section of either the blue or green wire to the main fan dark green/covered striped cable. If you prefer, you can touch base both of the dingy and green wires together.
1990-1996 COOLANT SWITCH INSTALLATION
1985-1989 NON B4P OPTIONED CORVETTES
1985-1996 Corvette Cylinder Head Plug Removal/ Switch Installation
BEWARE OF HOT COOLANT!! Drain the coolant at the radiator petcock. The radiator petcock is located on the passenger side of the radiator below the bring dow radiator hosepipe.
Remove the 5/16″ square deep-set pipe plug away betwixt spark plugs one and three on the drivers side of the engine. This tin can be very difficult. We suggest warming the area with a propane torch, then applying wax to the plug and encompassing area to help loose the male plug. To avoid cylinder head damage, do non use of goods and services an alkyne torch. Ahead the secure begins rounding out, stop and reapply the heat and mount.
Once the plug is abstracted, install the new switch. This tack relies on the cylinder head for a ground tour. Apply a small amount of sealer to ensure a good ground.
Wiring Instruction manual
Tie the modern harness to the switch and path the leads over to the rooter relay race affixed happening the radiator caparison. The cooling devotee relays are mounted on the driver side of the radiator housing. 1990-1993 Corvettes have two relays: a first and a secondary. 1994-1996 have three relay race: primary, secondary and one electrical relay for one-half cannonball along fan operation.
1990-1993 Corvettes will have the dark green operating theatre grim wire spliced into the fan electrical relay with the brunette super/white striped wire for primary feather fan control. This works best for stock or mildly altered engines.
Highly modified engines work best when both of the fans come on at the same time. Marry the unlighted green wire from the new harness to the night chromatic/white striped wire at the primary relay. Splice the navy blue electrify from the new fan switch rule to the secondary electrical relay with the navy/white striped telegram.
1994-1996 Corvettes: Site the relays with four wires (unmatchable relay has quintuplet wires for uncomplete hurry operation). Splice the dark green wire from the new harness to the relay with the dingy green wire for primary sports fan operation.
Extremely modified engines work best when both of the fans seminal fluid on simultaneously. Splice the dark green wire from the bran-new harness to the dark common wire at the primary electrical relay. Splice the navy blue wire from the new fan switch harness to the secondary relay with the dark sorry wire. There wish be atomic number 102 wires spliced to the five wire relay.
2007 Corvette Cooling Fan Control Module Ground Location
Source: https://tech.corvettecentral.com/2011/02/1984-1996-corvette-cooling-fan-control-modifications/