My recently acquired 87 Eldo is running a little hot at idle. I have flushed the system, installed new thermostat, new cap (tested it to 15 psi) and new coolant (50:50) with GM sealant tablets.

It runs almost dead-on at 195 deg except when sitting at idle. Yesterday the temp went up to 225 (outside temp 55 deg). I checked and there are no error codes indicating any sensor failure.

The radiator fan airflow seems very weak when it runs, which is very infrequently. The engine cools down a little when I turn the AC on and the AC condenser fan runs. I am tempted to run a wire/switch to the AC sensor so I can manually turn that fan on when needed.

Is there something wrong with the radiator fan or could it be something else?

Thanks,

PeteC

225 after idling a bit seems right on the money. That is just about when my fans come on. At what temp do your fans come on?

The fan came on at about 205 and then shut off after running about 10 seconds. It didn't come on even when the temp was up to 220. I was checking this in the garage with the radiator cover removed so I could see the fan. The temp didn't get above 220 like it did earlier in the day when I was out driving.

As heat sensitive as these engines are I get a little nervous with the temps up that high. Maybe I am worrying over nothing.

You can test the fans by going to the onboard diagnostics (push the "OFF and "WARM" buttons simultaneously and hold until the segment check appears) and selecting BCM override. Select BS04 and hold down the warm button. The fans should start to turn faster and faster as the "99" approaches on the display.

Edehall,

Thanks. I ran the test and the fan ran at increasing speed like you said. It was really going fast when it got to 99.

Does this mean everything is OK as far as the fan and fan control sensors are concerned?

PeteC

I think you're worrying over nothing. 225 isn't hot at all. Since the temperature stops rising at the point the fans turn on it seems like the system is in control. With the correct 50/50 mix and a 15psi cap the system wont boil until 265 so you're nowhere near "overheating".