Took my 1985 2.8 XJ and gutted it and I have installed a 4.3 GM with 700R4 and GM NP231 transfercase. Motor is a .030 over flat top forged pistons, comp cam with TBI injection with 3 inch exhaust also 8.8 rear axle with matching 3:73 gears. 5.5 inch rubicon lift, rear is S10 bastard pack with boomerang shackles and 33 X 10.50 BF Baja racing tires.
All is well except for the cooling department. Bought a new 21 X 19 aluminum 2 core,1 inch tubes Northern Performance radiator, cross flow radiator with 3 inch tanks with GM inlet and outlet. 16 inch electric fan with fan switch in tank of radiator, tried a 180 thermostat in engine now have a 195 degree thermostat, fan cycles on and off idling or around town but at highway speeds it heats up to 230+. Slow down and temp cools off weather is cool now but summer will be here next year and I know its not right now. New radiator, new 16 lbs pond cap, coolant overflow tank, new thermostat twice 185 first now 195, new water pump spaced hood up 1 inch at hinges to see if that would help not much differant. I was told to restrict the flow on one of the hoses, maybe water was circulating to fast didnt help. Opened up cross member in lower front of radiator to allow some more air flow but all ths helped very little. Have mechanical temp gauge to know real temp, factory gauge read hot also. Had condenser installed but not working, removed it completely for more airflow no help though.
Anyone have any ideas??
All is well except for the cooling department. Bought a new 21 X 19 aluminum 2 core,1 inch tubes Northern Performance radiator, cross flow radiator with 3 inch tanks with GM inlet and outlet. 16 inch electric fan with fan switch in tank of radiator, tried a 180 thermostat in engine now have a 195 degree thermostat, fan cycles on and off idling or around town but at highway speeds it heats up to 230+. Slow down and temp cools off weather is cool now but summer will be here next year and I know its not right now. New radiator, new 16 lbs pond cap, coolant overflow tank, new thermostat twice 185 first now 195, new water pump spaced hood up 1 inch at hinges to see if that would help not much differant. I was told to restrict the flow on one of the hoses, maybe water was circulating to fast didnt help. Opened up cross member in lower front of radiator to allow some more air flow but all ths helped very little. Have mechanical temp gauge to know real temp, factory gauge read hot also. Had condenser installed but not working, removed it completely for more airflow no help though.
Anyone have any ideas??
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