Warning: Grille block overheat

[aerohead]

Just a quicky.I took the T-100 out to New Mexico for the Thanksgiving holiday.On the return leg,climbing out of the Tularosa Basin up to Cloudcroft,New Mexico( elevation 8,650-feet ),the T-100 spit out some coolant when I pulled into a station for fuel.---------------

The temperature gauge never indicated it,but the engine ran hot on the steep ascent,with slow road speeds and low ram-air through the trashcan lid.So it looks like the block is defeated in hard mountain driving without electric-fan backup,something I'll now consider for future.-------------------

No harm came to truck but I felt bad about the spilled coolant. At 600 miles from home,I was thankful for no break-downs,and at 297,000 miles am pleased with what Toyota builds.--------------

I'll be looking into a new sending unit for the temp gauge.---------------------

All you grille-blockers be careful!!!!!!!!!!!!!!!!!!!!!!!!!!! I'll post data for the trip Saturday.

[red91sit]

I have noticed this temperature gauge problem on a lot of modernish vehicles. If it's at the red end, it's most likely too late. I'm thinking some of this can be attributed to build up on sensor, or just not sensetive enough of sensors.

I know on my Hondas, you can actually see the thermostat open and close on the coolant temp. sensor.

Thanks for the heads up!

[Cd]

My '93 civic's stock sensor is crap. Several times I have had coolant spill over and the guage reads normal.

[Clev]

I've read that some cars (notably Fords) have an oil pressure gauge that's essentially a glorified idiot light. It always reads normal except when pressure is far too high or zero, and then it indicates (too late) that the pressure is out of range.

That's the reason I haven't done any grill block on my Accord until I install a "real" temperature gauge/sender. I just don't know how accurate the thing is.

[MetroMPG]

Thanks for the reminder, Phil.

"Caveat modder"

.

[Frank Lee]

I'm not putting mine back on until I figure out some sort of dash-controlled opening.

[orange4boy]

I also had a coolant loss recently. I'm going to build this autospeed temperature switch soon and hook up my fan to it. I'm running a partial grille block too.

How about this for wacky:

My temp gauge goes up to a certain point then starts going down when it is getting hot. I have a separate new oil temp probe so I know which way things are trending. This is probably age related and perhaps a Toyota speciality. I know in kilns the bi-metal temperature probes change over time so you have to test them every once in a while.

Good idea, this alert.

[aerohead]

Originally Posted by orange4boy

I also had a coolant loss recently. I'm going to build this autospeed temperature switch soon and hook up my fan to it. I'm running a partial grille block too.

How about this for wacky:

My temp gauge goes up to a certain point then starts going down when it is getting hot. I have a separate new oil temp probe so I know which way things are trending. This is probably age related and perhaps a Toyota speciality. I know in kilns the bi-metal temperature probes change over time so you have to test them every once in a while.

Good idea, this alert.

I've seen some FLUKE digital temp meters relatively cheap at pawn shops lately.'Thought I might pot the thermocouple near original sending unit for a "second source" of data.---------- Also,a rotary switch would allow multiple feeds from additional thermocouples at oilpan,trans,differential,etc.------------- Sounds as if the original gauge setups on many cars are of dubious value.

[i_am_socket]

I think it was my Tempo that had a funky temp gauge. It lost contact somewhere so it shot up to the highest point. Scared the crap out of me; I thought it would explode. I even parked it with the hood open to let it cool off.

I'm starting to rethink my "automatic" adjustable grill block plans...

[Clev]

Originally Posted by orange4boy

How about this for wacky:

My temp gauge goes up to a certain point then starts going down when it is getting hot. I have a separate new oil temp probe so I know which way things are trending. This is probably age related and perhaps a Toyota speciality. I know in kilns the bi-metal temperature probes change over time so you have to test them every once in a while.

Good idea, this alert.

My Ranger does something similar. It will occasionally slowly climb very high, and suddenly, about 3/8 of an inch before it hits the "Hot" mark, it will quickly return back to normal. The first few times this happened, it started plummeting just as I was starting to look for a place to pull over.

In my case, I think the thermostat occasionally gets stuck and doesn't open until much later. I've learned to live with it, but I always keep an eye on it, especially when it's hot out or I'm towing.