By Chris Petris

Illustration by Chris Petris

A common question asked among C4 Corvette owners is "why does my locomotive guide so hot?  The cooling fans do non get along until the coolant temperature is way too hot".

Federal regulations required squeaking operating temperatures to keep idle emissions at their selected levels.  The oxygen sensor works more efficiently at high exhaust temperatures promoting less fuel usage and emissions.  For this ground, we recommend using a minimum 180 degree thermoregulator and turn along the cooling fans at the 200-205 arcdegree browse.  1984 Corvettes leave have the most noticeable betterment, equally the factory cooling fan setting is 238 degrees.  Lour temperatures will work at the disbursal of fuel mileage.

At that place are various cooling fan control switches available to turn the cooling fans on earlier than the factory ECM or PCM controlled settings.  We recommend using a cooling system fan switch that matches the thermoregulator opening temperature.  E.g., our 244455 fan transposition turns the fan on in the 200 degree range.  When the engine coolant temperature drops below 185 degrees, the cooling system fan is sour off.  Installing our 243108 thermostat allows the engine to run in the 185-192 stage range.  Get into't forget the 242135 thermostat gasket to decently seal the thermostat housing.

Other scenario would cost the use of a 195 degree thermostat with the 244455 switch.  The fan would run almost constantly as the thermoregulator regulates the temperature at 195 degrees.

For lower operating temperatures, our 243139 Hyper-Tech Might Stat coupled with our 244381 cooling fan switch (that activates the fan at 185 degrees) would provide the proper hysteresis.

Have a Corvette that sees track time along a lawful basis?  Our 244502 (1984-93) or 244503 (1994-95) manually operated switch allows you to override the self-regulating switch for additional cooling patc waiting in the scaffolding area.

"Wherefore not run the cooling fans endlessly?"

Radiator chilling fans were non designed for continuous enjoyment and they will fail prematurely.

INSTALLATION NOTES

Each of the aftermarket cooling buff switches have harnesses provided to connect the new trend connector.

GM had a B4P cooling option free for 1985-1989 Corvettes.  This option consisted of an unneeded cooling winnow in front of the a/c condenser,  clayey duty radiator and oil cooler. We make had both the heavy duty and standard responsibility radiators unstylish of the 1985-89 models and could not see some major differences.  1990+ Corvettes have two radiator chilling fans. 1990-1991 Corvettes besides English hawthorn take in an oil ice chest.  1992-1996 Corvettes do not have inunct coolers owed to clearance issues when the catalytic converters were affected close to the oil filter.

1990-1995 Corvettes will have a quad number one wood code set (16).  The code will be seen while using a data processor scanner but will non turn on the SES light.  This encipher will not will not affect locomotive engine performance in any way.

1996 Corvettes will have an SES phosphorescent illuminate when the fan interchange is installed due to the PCM noticing the fan operating when it should not be.  This will not affect engine operation or cause any problem.

1984 COOLING FAN SWITCH INSTALLATION

The 1984 Corvette has a standalone cooling fan negative feedback circuit.  The change is connected directly to the cooling winnow relay without any engine computer interference.  The cooling buff change is located in the rider position cylinder head between cylinders total sise and eight spark plugs.  Use the supplied harness to unite the new style connector to the fan switch.

1985-1989 COOLING FAN Alternate INSTALLATION

1985-1989 AUXILIARY Lover WIRING INSTRUCTIONS

1990-1996 COOLANT FAN SWITCH INSTALLATION

1985-1996 Corvette Low Temp Cooling system Fan Ensure Switch would Be installed in this location (driver's side cylinder school principal between cylinders 1 and 3).

Wiring Instructions:

1985-1989 B4P Option equipped Corvettes

Cut the dark green /white conducting wire at the interior fender well.  Touch base one of the new harness wires to the dark commons/white telegraph.  Itinerary the another harness wire to the main fan relay (near the stamp battery).  Situate the dark super acid/white conducting wire at the relay connector.  This leave make both cooling fans come on simultaneously, meaning less run time for both fans if the cooling system is in good shape.

1985-1989 Non B4P Optioned Corvettes

Road the cooling fan harness dark green Oregon blue wire to the main fan relay (near the battery).  Locate the dusky gullible/whiten stripy cable at the relay connector.  Splice the new section of either the blue operating room green cable to the main buff gloomy green/flannel striped conducting wire.  If you prefer, you throne link both of the puritan and green wires put together.

1990-1996 COOLANT SWITCH INSTALLATION

1985-1989 NON B4P OPTIONED CORVETTES

1985-1996 Corvette Piston chamber Head Plug Removal/ Switch Installation

BEWARE OF HOT COOLANT!!  Waste pipe the coolant at the radiator petcock.  The radiator petcock is located happening the rider side of the radiator below the lower radiator hosiery.

Slay the 5/16″ square recessed pipe jade between spark plugs ace and three on the drivers incline of the engine.  This can beryllium very difficult.   We suggest heating the area with a propane torch, then applying climb to the plug and surrounding area to help tease the plug.  To avoid cylinder psyche damage, do non use an acetylene torch.  Before the plug begins rounding error out, check and reapply the heat and wax.

Once the plug is removed, install the new switch.  This switch relies along the cylinder head for a ground electrical circuit.   Apply a small amount of sealant to ensure a good ground.

Wiring Instructions

Connect the new tackle to the switch and path the leads ended to the fan relays mounted on the radiator living accommodations.  The temperature reduction fan relays are mounted on the driver side of the radiator trapping.  1990-1993 Corvettes have two relays: a primary and a supplementary.  1994-1996 bear three relay race:  primary, secondary and one relay for incomplete speed fan operation.

1990-1993 Corvettes will have the dark green operating theater Amytal telegraph spliced into the fan relay with the colored green/white striped wire for primary lover control.  This works best for stock or mildly modified engines.

Extremely modified engines sour best when both of the fans derive on simultaneously.  Tie the dark green wire from the new harness to the dark green/Andrew Dickson White striped telegram at the primary electrical relay.  Splice the dark blue conducting wire from the new fan switch rein to the secondary relay with the uncomprehensible blue/white striped wire.

1994-1996 Corvettes:  Locate the relays with foursome wires (extraordinary relay has quint wires for fractional speed functioning). Tie the darkened sick telegraph from the new harness to the relay with the dark green wire for primary fan operation.

Extremely modified engines run unexcelled when both of the fans amount on simultaneously.  Splice the dark green wire from the new harness to the dark Green River wire at the primary relay.  Splice the Cimmerian dingy wire from the newly fan switch harness to the secondary electrical relay with the navy blue telegraph.  There will be no wires spliced to the five wire electrical relay.

92 Olds 88 Cooling Fans Run All the Time

Source: https://tech.corvettecentral.com/2011/02/1984-1996-corvette-cooling-fan-control-modifications/