Overheating, maybe... - '90 Westy 2.1L

[RBEmerson]

Looking at the temp gauge on the dash, the needle comes up to the usual place and stays put. The radiator fan doesn't come on (it works - I jumpered the switches).

Sitting in front of the garage, idling, the T2 temp comes up to about 204F (95.5C) using ScanGauge (I verified it reads T2). I've seen 207F (97.2C) at a traffic light. Reading the water pump housing with an IR gun, I get about 198F (92.2C).

The gun showed about 150F (65.5C) at the inlet side of the radiator, at the top.

So... is T2 telling me tales? What a reasonable temp range from T2?
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Lord, give me coffee to change the things I can change, and wine to accept the things I can't change.

[outcaststudios]

i dont know about t2, but the temperature that steam happens at is 212º id say youre doing ok for temps. plus youre taking all those readings from differnet points no? the average seems ok.
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'88Doka JX td
'69 westy
(rip)couple bugs
(rip)three type III"s
(rip) '81 vanagon
a bunch of french stuff,and 9 motorcycles.

https://www.thesamba.com/vw/classifieds/detail.php?id=2573791

[dobryan]

[RBEmerson]

Very true - one of the point of points of pressurized cooling systems is to hold off the boiling point.

I'm inclined to think the cooling system isn't in big trouble, but the T2 numbers aren't comforting.
_________________
Lord, give me coffee to change the things I can change, and wine to accept the things I can't change.

[outcaststudios]

[Ahwahnee]

[outcaststudios]

that makes total sense,really glad to know that now. seems like OP's temps are really good then?
_________________
'88Doka JX td
'69 westy
(rip)couple bugs
(rip)three type III"s
(rip) '81 vanagon
a bunch of french stuff,and 9 motorcycles.

https://www.thesamba.com/vw/classifieds/detail.php?id=2573791

[RBEmerson]

50/50 anti-freeze and water both raises the boiling point, and lowers the freeze point. It's all in the chemistry of the mix.

Folks who live well above sea level are aware that water boils sooner than at sea lever - reduced air pressure. The pressure cap stands things on their head and lets the pressure inside the coolant system go above sea level pressure - 13-15 PSI being typical.

My concern is the T2 sensor is hot, hot, hot - mostly just below 200F (93.3C), but sometimes above it. At the moment, ambient temps are still cool (nominally 30 - 60F / -1 - 15C). What happens when we start hitting 70 - 80F (21 - 26.6C)?

Or is everything OK, and I should stop looking at the T2 readout?
_________________
Lord, give me coffee to change the things I can change, and wine to accept the things I can't change.

[crazyvwvanman]

If you look in the full Bentley it shows the 3 different watercooled engine cooling systems.
Each describes the thermostat test opening range.
Each says thermostat BEGINS to open at 185f.
Each says thermostat FULLY open at 221f.

Mark

[RBEmerson]

Do you recall where you saw that in Bentley? I expected to find what you're talking about, but no luck so far.

One consolation is apparently temperature regulation is going on. T2 stays in a range (nominally 193-203F - 89.4-95C), instead of "goes up and stays there".

I replaced the full thermostat housing and thermostat a while back. The housing looked ...meh... ratty? Rather than have it surprise me on the road, I replaced it. Get that far, might as well do the thermostat, too. ;D
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Lord, give me coffee to change the things I can change, and wine to accept the things I can't change.

[crazyvwvanman]

Later Bentley cooling system info, thermostat temps

1.6 diesel page 19.4

1.9 wbx page 19.8

2.1 wx page 19.11

page 19.12 has additional important info

[RBEmerson]

Thanks!
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Lord, give me coffee to change the things I can change, and wine to accept the things I can't change.

[RBEmerson]

I don't understand the cooling system's sensors' function(s).

T2 and T1 don't report the same values (ScanGauge, and instruments, respectively). Why is that, and why does (I'm assuming) the ECU care about T2 v. T1?
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Lord, give me coffee to change the things I can change, and wine to accept the things I can't change.

[kamzcab86]

[RBEmerson]

OK, the fog slowly dissipates...

Recently I did a 100 mile round trip to collect wood shakes for a roof I'm replacing.

On the way out, in the rain and ambient temps in the 50's. and on the way back, ambient temps still in the 50's but no rain, and 3 squares (or ~300 sq ft) of shakes (ain't light!) in the back, T2 stayed about the same, and the temp gauge stayed in the usual place (bottom of the operating range markings).

Way back when, T2, as best I can recall, stayed much lower than it currently does. Maybe that was a problem (engine temp too low), and all's well now.

All of this makes for a strong argument to ignore the darn ScanGauge, believe what I see next to the tach, and got on with life. Except just maybe all isn't as it should be. Hence the thread title. ;D
_________________
Lord, give me coffee to change the things I can change, and wine to accept the things I can't change.