overheating

[Jester]

Hi guys, here is the issue:
Van started overheating today out of the blue.

Symptoms and observations:

-coolant in good shape, full.
-overflow at proper level
-upper rad hose hot, but not overpressured.
-lower rad hose cold
-no leaks observed anywhere.


What do you think? Would the lower being cold suggest a thermostat stuck, or a water pump failure?

Not sure if I wrote all the details, so ask and I will check if there is anything else.

[Jester]

Oh, a couple more details:
-overflow reservoir is cold.
-after stopping checked the rad again, no leaks but the lower part of the rad and the lower rad hose are completely cold. Only the top part of the rad is hot.

So I'm guessing the coolant is either not circulating at all or very slowly.

My bet would be on the thermostat.
In my experience a catastrophic loss of the water pump function is less likely, unless the belt broke or the pump seized.
What do you think?

[glenn]

My van suddenly started overheating once - the temp gauge suddenly went over 3/4 and hot freaked me out. I turned the van of immediately waited for it to cool, started it up again - same thing. Turned out it was just a bad sensor. If everything else is normal, it could be this simple.

[Jester]

I just went out to the van after it sat for some 4hrs or so, and after turning the ignition on the temperature gauge shot all the way just under the red, same spot as before.

So I'm confident it's a faulty sensor.

So now the question is, where is the sensor located, and does Lordco carry replacements?

[FalcoColumbarius]

The sensor is beside number one cylinder, just behind the top of the timing belt cover. Try wiggling it. CVI should have them if you have no luck at Lordco.

Falco.

[Jester]

Found it, thanks.

If anybody has a part# handy, I'd owe you a beer.
Otherwise I'll see if the parts subforum has the answer.

[Jester]

So my research came up with:
Mitsubishi part# MD050214

Lordco part# WT405

Blue Streak aftermarket
Part# TS299

And more:

http://www.autopartoo.com/oem/mitsubishi/md050214.html

[Jester]

Just to close this issue, the temp sensor part# I found turned out was correct, threads correct, plug correct.
The part was bought from ebay for $22 shipping in(Australia).
I'm sure local dealers have it in stock, I just didn't have the time or energy to call around, drive around and get it.

Napa and Lordco technically can get them too, but 1. they're not a regular stock item, and 2. Price is somewhere closer to $45.