thesameguy
Well-known member
- Joined
- Jun 6, 2014
- Posts
- 623
The '93 Southwind spent the last 16 months doing nothing, which isn't how I like it, but it's how it is. Was. Yesterday I finally had an opportunity to take it out, and the first (only) thing odd I noticed is that sitting in traffic, it gets warmer than I think it should. Here's some data I collected:
1. Thermostat seems to be fine - after ~10m the upper radiator hose starts warming up quickly and stays hot
2. The main clutch driven fan is difficult to spin when cold - give it a push and it stops immediately
3. At cold start, the main fan is spinning full speed, as expected
4. After the engine has been run up to temperature, the main fan is a little easier to push, but stops within 60 degrees, it won't spin freely
5. There is an electric pusher fan up front, it cycles normally
6. I flushed the cooling system about 18 months ago, it came out 100% clean, and it still looks 100% clean
7. When cold the overflow bottle is at the cold mark, when hot the overflow bottle is at the hot mark
8. On the road, engine temp is very consistent at ~203F at the ECT sensor (according to Tech 2)
9. Sitting in traffic, however, engine temp creeps up to 221F at the ECT sensor and it will not cool down. Ambient temp is around 60F.
To be fair, I'm not sure if this is how it's always been. Something in the last 16 months has affected the instrument cluster - the voltmeter shows 12v but my aux voltmeter shows 14.1v at the chassis battery, and Tech 2 shows 13.5v at the ECM. But the thing that caught my eye is that in traffic the temperature gauge is sitting on the border or Normal and Red, which seems like it should be ~240F but, again, Tech 2 says the actual engine temp is 220F. So the voltmeter reads low and the temp gauge reads high...
It's possible that the engine has always run at these temps, and crappy '90s GM instruments are filthy liars.
Nothing I've found indicates anything is wrong per se, but 220F seems hot, even for an iron block 454. The only thing I can actually find "wrong" is that Tech 2 says the target idle speed is 750rpm, but I'm idling at 900rpm. Not sure if that's normal (I've literally never looked before) or maybe a vacuum leak or a sad idle valve.
Does anyone have any reactions or thoughts?
1. Thermostat seems to be fine - after ~10m the upper radiator hose starts warming up quickly and stays hot
2. The main clutch driven fan is difficult to spin when cold - give it a push and it stops immediately
3. At cold start, the main fan is spinning full speed, as expected
4. After the engine has been run up to temperature, the main fan is a little easier to push, but stops within 60 degrees, it won't spin freely
5. There is an electric pusher fan up front, it cycles normally
6. I flushed the cooling system about 18 months ago, it came out 100% clean, and it still looks 100% clean
7. When cold the overflow bottle is at the cold mark, when hot the overflow bottle is at the hot mark
8. On the road, engine temp is very consistent at ~203F at the ECT sensor (according to Tech 2)
9. Sitting in traffic, however, engine temp creeps up to 221F at the ECT sensor and it will not cool down. Ambient temp is around 60F.
To be fair, I'm not sure if this is how it's always been. Something in the last 16 months has affected the instrument cluster - the voltmeter shows 12v but my aux voltmeter shows 14.1v at the chassis battery, and Tech 2 shows 13.5v at the ECM. But the thing that caught my eye is that in traffic the temperature gauge is sitting on the border or Normal and Red, which seems like it should be ~240F but, again, Tech 2 says the actual engine temp is 220F. So the voltmeter reads low and the temp gauge reads high...
It's possible that the engine has always run at these temps, and crappy '90s GM instruments are filthy liars.
Nothing I've found indicates anything is wrong per se, but 220F seems hot, even for an iron block 454. The only thing I can actually find "wrong" is that Tech 2 says the target idle speed is 750rpm, but I'm idling at 900rpm. Not sure if that's normal (I've literally never looked before) or maybe a vacuum leak or a sad idle valve.
Does anyone have any reactions or thoughts?