OK, as described in my other post "Real time temperature measurements...", I put a thermocouple on to measure my coolant temps. Here are some numbers for comparison if you are interested. Those of you who have a wet probe system, or are connected to OBD, I'd love to read some of your numbers to gauge where I'm at.
Outside temperature: about 75F, 50% humidity (guessing) (around 10pm, nice and comfy!)
A/C on.
Original -I think- 97 radiator with 50% Toy red. New thermostat. Fan clutch seems to be OK and no HG bubbles to be seen...
Started to idle the engine from cold.
After about 15 mins, the thermostat opened when my coolant gauge (located at the exit of the head) was at about 172F or so. The FSM says it should open/close between 176 and 183, so pretty close.
Another few minutes, say after 20 mins total and the temp was about stabilized at 185F or so (700 rpm idle). I imagine this means that the thermostat was not fully open and the temp had reached an equilibrium.
Then went driving. I climbed a little mountain with a reasonable slope (about 2000 ft elevation gain in about 5 miles, 6% max or so IIRC. I drove it up at about 50 mph at around 2000 rpm. The temperature climbed in a few minutes to around 200F but never went above 205F.
Then I coasted down, the temp dropped back to 185F or so again, where I imagine the thermostat started to close partially again.
Drove around a bit on flat. At the bottom of the mountain, I let it idle right after that and it stabilized around 194F, and would have slowly gone down I guess to somewhere between 194F and the 185 I got earlier but I shut it down then. It immediately went back to 201F with the engine off. Interestingly, almost as much as after climbing the mountain. That's no circulation for ya!
Went back an hour later, started to idle. Saw the thermostat open again at 173F or so, and stabilized around 186F so very similar to before.
[Oh, and, btw, all of the above with the OEM dash gauge firmly pegged a hair below center and never moving one bit... sheesh...]
Now I don't know if these numbers are good. I think my cooling system is in top condition and this was not a trivial climb. Max temp was only 205F. My gauge may be a few deg F on the low side. I was lightly loaded and not towing. How does that sound compared to your numbers?
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added. New test:
2 pm, same mountain, same speed. Now 85F outside in the shade.
Up. A/C on, 2000 rpm, 45 mph, started idling at 196 after some low speed driving. Climbed, at top of mountain 221 max temp.
Coasting down: 185.
Note: 10F higher max temp than yesterday with about 10F higher ambient temp.
second test. Same thing, same speed but A/C off now.
Max temp at temp only 210 with most of climb up hill around 201.
Coasting down A/C off: 181.
So turning the A/C off gave me 10F lower max temp. Worth it if things look too hot.
Drove freeway 2200 rpm, 65 mph, temp between 191 and 194 with outside temp ranging from 83 to 76.
Idling I stayed at 200. Turned the engine off and the temp shot up to 207. (Note may be better off to keep it idling if you want to avoid overheating?)
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drove around in the burbs tonight. No hills. A/C off. Avg speed something like 40mph maybe. Outside temp 70F. Temperature of coolant stabilized at 186 or just a tad above a fully open thermostat (per the FSM).
Outside temperature: about 75F, 50% humidity (guessing) (around 10pm, nice and comfy!)
A/C on.
Original -I think- 97 radiator with 50% Toy red. New thermostat. Fan clutch seems to be OK and no HG bubbles to be seen...
Started to idle the engine from cold.
After about 15 mins, the thermostat opened when my coolant gauge (located at the exit of the head) was at about 172F or so. The FSM says it should open/close between 176 and 183, so pretty close.
Another few minutes, say after 20 mins total and the temp was about stabilized at 185F or so (700 rpm idle). I imagine this means that the thermostat was not fully open and the temp had reached an equilibrium.
Then went driving. I climbed a little mountain with a reasonable slope (about 2000 ft elevation gain in about 5 miles, 6% max or so IIRC. I drove it up at about 50 mph at around 2000 rpm. The temperature climbed in a few minutes to around 200F but never went above 205F.
Then I coasted down, the temp dropped back to 185F or so again, where I imagine the thermostat started to close partially again.
Drove around a bit on flat. At the bottom of the mountain, I let it idle right after that and it stabilized around 194F, and would have slowly gone down I guess to somewhere between 194F and the 185 I got earlier but I shut it down then. It immediately went back to 201F with the engine off. Interestingly, almost as much as after climbing the mountain. That's no circulation for ya!
Went back an hour later, started to idle. Saw the thermostat open again at 173F or so, and stabilized around 186F so very similar to before.
[Oh, and, btw, all of the above with the OEM dash gauge firmly pegged a hair below center and never moving one bit... sheesh...]
Now I don't know if these numbers are good. I think my cooling system is in top condition and this was not a trivial climb. Max temp was only 205F. My gauge may be a few deg F on the low side. I was lightly loaded and not towing. How does that sound compared to your numbers?
-----
added. New test:
2 pm, same mountain, same speed. Now 85F outside in the shade.
Up. A/C on, 2000 rpm, 45 mph, started idling at 196 after some low speed driving. Climbed, at top of mountain 221 max temp.
Coasting down: 185.
Note: 10F higher max temp than yesterday with about 10F higher ambient temp.
second test. Same thing, same speed but A/C off now.
Max temp at temp only 210 with most of climb up hill around 201.
Coasting down A/C off: 181.
So turning the A/C off gave me 10F lower max temp. Worth it if things look too hot.
Drove freeway 2200 rpm, 65 mph, temp between 191 and 194 with outside temp ranging from 83 to 76.
Idling I stayed at 200. Turned the engine off and the temp shot up to 207. (Note may be better off to keep it idling if you want to avoid overheating?)
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drove around in the burbs tonight. No hills. A/C off. Avg speed something like 40mph maybe. Outside temp 70F. Temperature of coolant stabilized at 186 or just a tad above a fully open thermostat (per the FSM).
)
