Temp Gauge Actual Temperatures?

[Swiftus]

So it was what, 80* F today? That engine temp doesn't seem too far from stock. Considering that you have essentially the 'year-round' T-stat in the cooling system right now, I would say that everything looks normal.

What may have made you a bit edgy last weekend was that the ambient air temps were up in the 90s... which could easily make the engine run hot on a year-round t-stat.

So, from what I can make out, your radiator alone will produce a temp differential of about 5C, and with the fan on that differential increases by 5. What this tells me is that above 40 or 50mph, you can expect the 25C drop across the radiator, and anything under those speeds may use the electric fan to help with cooling.

From what I read earlier in the thread, I think that your normal operating temps today were pretty close to factory. Maybe for the DC summer you will want to get a lower temperature t-stat for those traffic situations, but I think that your cooling system is functioning just fine.

[M3M3]

your first pic is where my S14 sits in traffic on 90+ deg day with 12in elec fan and heat on.... i have stock S14 tstat, which i believe is a 91C.

your car looks fine...

drive it on the highway for ten min at speed, see what it does then.

[TobyB]

Temperature of bottom radiator hose: 197F (91.7C)

oh, your rad is heat- soaked.

Even the 160 lower hose temp is kinda high- get out on the freeway

and see what it is... heh.. j/k!

If my gauge showed the upper temp, the VDO would say 210.

The lower (fan on) would be right around 200.

(this has become a fun post)

t

[M3M3]

Good catch on the lower number toby. Should be much bigger temp drop accross the rad.

[Swiftus]

I didn't know what was normal in a rad-only condition. Could this be a bad radiator cap issue? No pressure would mean less ability to absorb heat.

[ClayW]

Temperature of bottom radiator hose: 197F (91.7C)

oh, your rad is heat- soaked.

Even the 160 lower hose temp is kinda high- get out on the freeway

and see what it is... heh.. j/k!

If my gauge showed the upper temp, the VDO would say 210.

The lower (fan on) would be right around 200.

(this has become a fun post)

t

So, I'm only dropping 6.5F sitting still and idling with no fan on. Sitting still and idling with the fan on, I drop 25.5F.

I'm sure that the numbers will change on the highway, but it's hard to get under the hood at 70mph (heheheheh).

It's a new radiator and a new cap.

Hopefully, Jake will post his findings. I'll also report back when I install the lower thermostat.

[ClayW]

Driving around with the electric fan on:

Temperature of top radiator hose: 185F (85C)

Temperature of bottom radiator hose: 132F (55.6C)

IR gun pointing at the temp sender up under the intake: 183F (83.9C)

[Swiftus]

You, my friend, have what seems to be a perfectly normal functioning coolant system with possibly too warm of a t-stat.

[jakeb]

I haven't had the chance to drive mine and check the temps yet. I have been busy swapping a GM overdrive automatic into my Dad's studebaker Avanti.

I will take the 02 for a drive this eve and report back with what I find.

[jakeb]

Here is what I came up with

After driving it around, come home and idling

187F top hose(near tstat housing)

175F bottom hose

187F at the sensor in the head

after sitting for a few the fan kicked on and here are the readings agan

200F - top

190F - bottom

197F - sensor

I am using a stock m42 tstat, stock m42 radiator heater is hooked up but turned off(no flow). I have been running it this way for almost 5k miles

It sounds like ours are pretty similar..... I think you are fine.

[TobyB]

Temperature of top radiator hose: 185F (85C)

Sounds like everything is good, except maybe your electric fan is

a bit on the small side.

t

[Swiftus]

Temperature of top radiator hose: 185F (85C)

Sounds like everything is good, except maybe your electric fan is

a bit on the small side.

t

Or maybe its mounted too far from the radiator?

[ClayW]

Temperature of top radiator hose: 185F (85C)

Sounds like everything is good, except maybe your electric fan is

a bit on the small side.

t

Or maybe its mounted too far from the radiator?

Really? It's a 16" electric fan mounted right to the front of the radiator with those plastic tie things.

[M3M3]

noticed in your pix an elec fan mounted BEHIND the radiator. is that the fan you are refering to? not to say that this is what is happening in your case, but whether mounted front or rear make sure it is wired so that the fan is pushing or pulling air front to back through the radiator. i mention this because it is easy to reverse the wires, and the purple M2 i acquired had this issue when i got it...the "pusher" fan in front of the radiator was pushing air out the front of the car, not through the radiator. kinda did not work well! :-)

[jgerock]

Found the temperature scalings in the June 1978 Roundel (both Fahrenheit and Celcius)