SR Overheats frequently

[corey240]

Moslty happens when im going up steep consistent mountains and when i drift or cruise on the interstate. Other then that its fine. Ive bled the system countless times, and made shore its allways full of fluid. Im not running a thermostat and i have flex-a-lite dual fans.

I dont know if my sensor is malfunctioning or if there seriously is a problem. I allways have this worry my motor will go if it really overheats all the time. I kinda figure its why im on my 3rd turbo, which is why im worried now. Ive had 2 t25's and now im on a t28, so i dont wana blow it...literaly.

[blinker_fluid]

Make sure ur temp switch for the fan is set to 180 degrees and is working. Also squeeze the hoses to make sure ur water pump is working. How much boost are u running?

[corey240]

where is the temp switch

[IanS]

I would suggest getting a thermostat. OE cooling systems are designed to work a certain way. The thermostat is meant to restrict coolant flow, because if the coolant is flowing too quickly, it does not have adequate time to pull heat from the engine itslef, thus causeing overheating, especially at high revs.

I would also suggest an oil cooler, as the SR20s are notorious for overcooking their oil, pre oil cooler I was seeing oil temps nearing 210 degrees just cruising on the highway. High oil temps force the rest of the cooling system to work harder, if you cool the oil, the whole engine will run cooler.

[Kalypso]

Ian what thermostat do you recommend

[supreamS14]

I use fail-safe. It locks open If it over heats. Mine is locked open because my motor started to over heat. When I change to an all alm. rad. I will see if I can un lock it or I will buy a new 1. It also opens @ 170. I would think oem or nismo parts would be the recommended way to go but I like to do my own thing!

[IanS]

Ian what thermostat do you recommend

Thermostats are very simple, some people will suggest dealer parts, but in reality often times the OEM parts are just repackaged Stant or Wahler items. Others will say that a Nismo, TRD, or Mugen performance thermostat is the only way to go, but again this is not true. It is true that these are performance thermostats, but their only difference is the opening temp. Some will tell you that the lower opening temp will keep the engine cooler, when the truth is, most ECUs control engine temp using electric fans. This becomes troublesome on engines like the SR which do not have ECU controlled fans, the thermostat then controls engine temp.

People need to look past the misinformation. If you engine cant keep itself cool with a thermostat that opens at 185 degrees, how is having a thermostat open earlier going to change anything? If you have overheating problems a lower temp t-stat most likely wont help, unless your current t-stat is stuck closed, in this case, any working t-stat will fix the problem.

Is running cooler really better? Modern ECUs are designed to run in a certain temp range, running richer when either too hot or too cold so as to prevent detonation. If you lower your running temp, you are running the risk of dropping out of the specified operating temperature range, which can decrease mileage, increase carbon buildup, as well as shorten catalytic converter and oxygen sensor life.

The final answer? Get a quality thermostat with an opening temperature the same as marked in the FSM. Leave the performance t-stats for race cars, or engines with full engine management.

[shift_SRDETuser]

If you have the electric fans on your car why not just adjust the cut on switch down to like 170 or something. I use altima fans and I have the low speed engine fan and a/c fan turn on at the same time while the high speed engine fan is running off a thermostat on the radiator -- I may switch to a thermo switch in the upper rad hose though since this is more accurate. Why did Nissan not put electric fans on these cars to begin with -- I have no idea?

The electric fans are a lot more efficient.

[BigMACKenzie]

yeah, listen to the lumberjack dude, get a thermostat, you can also get a larger oil pan for your sr20 in addition to the oil cooler, a number of reliable manufacturers make this part and it can be had for a decent price (Greddy etc)

[IanS]

If you have the electric fans on your car why not just adjust the cut on switch down to like 170 or something.

Like I said before, If the engine wont stay cool with the fans coming on normally, what is lowering the turn on temp going to do?

Why did Nissan not put electric fans on these cars to begin with -- I have no idea?

There are not enough pins left in the ECU to control electric fans, the coilpacks take up too many wires.

The electric fans are a lot more efficient.

Not true, belt driven clutched fans do a far better job cooling an engine, as long as they have the proper cowling. People just like E fans because they do not draw on the engine.