[4R_in_Uzb]

Hi guys! I would really appreciate your help!
I noticed today that the lower radiator pipe coming into the engine is cold at all times. Is there a second thermostat down there?
I bought my Runner recently so I'm just getting to know the engine (don't have manual).
Please help!!!!
(it's a 1992, 3VZ-E)

[JP4RNR]

Sounds like a clogged radiator if the hose is cold and or a thermostat that is frozen shut

[jharris2]

If one hose is cold, then I'd expect the engine to be overheating. But you don't say anything about that. Any more details you can provide?

Otherwise, JP4RNR gives good advice to start with.

[4R_in_Uzb]

I don't hink the engine is overheating. I ran it for 15 min and the temp. meter didn't go beyond it's middle position. I'll try to drive it today carefully, see what happand then.
My heaters don't put out heat either, could this be because of the shut thermostat too?
I was told there may be two thermostats, is it true?

Thanks!

[4R_in_Uzb]

I just had my thermostat checked, it's new, opens at 88 degrees Celcius. My lower radiator hose is still cold. Radiator is not clogged. The temp meter dosn't show overheat but after about five munites of driving the coolant starts to squirt out of the little nosle next to the radiator cap (I don't have that (what is it called?) expansion tank thing). Not sure if it the sign of engine overheating?.. Where is the temperature sensor?.. Is it possible that the hot water doesn't reach it?

I was told it may be a cracked gasket, so I'm on my way to order new ones.

The heaters in the cab also put out cold air and never hot.

Does anybody have a better solution before I take apart the engine?...

Thanks a lot!!

[4R_in_Uzb]

Hi again,

here is the update. We got the heads out and it turns the gasket on the 6th cyl is thin, the piston is clean and wet. The water was coming out of the exhaust pipe.

I still don't know why the heaters aren't working and if the problem is connected to the burned gasket. ANd I still don't understand why the lower radiator hose was cold all the time...

While we were digging our way to gaskets, we found the idler and idler puller worn out, also found alternator and started bearings worn out. I think that is it.

I don't know why you guys aren't answering, but I'm hoping you are with me mentally...

Anyway, thanks for your help!!

[TheBlueWave]

I find it hard to believe that your engine isn't overheating if the return line from the main radiator (in front of the engine) isn't flowing coolant back to the engine. I don't know of any vehicles that have two thermostats...
I would simply tear apart the cooling system bit by bit until the problem can be found.
As for the heater not working, have you checked the heater core? It could be leaking or clogged in its own right. Also your heater will stop working when coolant level gets low. Its positioned at the "top" of the plumbing circuit so as to let coolant reach the engine when the level gets low.

R U sure you're not overheating or leaking somewhere? Maybe the bad gasket will fix your problem. More details please.

[4R_in_Uzb]

I might have been overheated once but I don't seem to have noticed it. Like I mentioned, I can't remeber seeing the temp gauge go all the way up (or right in our case). The radiator did spit coolant out from the little nossle under the car since I don't have the expansion tank. I had to add 1 litre.

The way I noticed the problem was that I noticed (what I thought was) smoke coming out the exhaust pipe, which later turned out to be steam. So the coolant leaked throught the head gasket and some was lost due to the missing expansion tank.

Your idea about heater not working because of the low coolant level seems right, I will check the system since the engine is already taken apart and I have a better access to all heating hoses and stuff. As for checking the heater core, it's located under the dash, isn't it? Also what about the rear heater, I heard it has a different line. How should I address that?

As for the second thermostat, yea, I was misled, sorry.

Thanks for your reply!!!

[TheBlueWave]

The cold return line still confuses me, but yes the head gasket will help you out to keep fluid in the system. Yes, the heater core is located in between the dash and the firewall, it can be a real SOB to deal with. It can be located by finding two small cooling hoses entering and exiting the firewall.
Good luck, keep us posted.
By the way, is it difficult to get parts in Uzbekistan?

[4R_in_Uzb]

Originally posted by TheBlueWave
The cold return line still confuses me,

By the way, is it difficult to get parts in Uzbekistan?

The cold return line confuses me too... I am starting to think I might have not waited long till the thermostat opens... I ran the engine for about 15 minutes in hot weather. Next morning I drove it for about 15 minutes and still it was cold. Maybe afterall I never got it to open.

But the steam in exhaust really alarmed. Also, one or two of the cylinders were "coughing" (is "missing" the word in this case?...).

About parts in Uzbekistan, some parts are available, mainly for more popular models like the nineties Corolla and stufflike that. Lots of parts for Uzbek/Korean Daewoo, we have their plant in Uzbekistan. Also plenty of parts of Soviet/Russian cars like Lada, Moskvich, Volga.
For 3VZ-E in particular I had to order parts from the Emirates, the closest parts source. The drawback of this deal is that you don't know the price till the parts arrive. And I'd expect parts to be at least twice expensive than in the US. In the meantime I'm waiting for the parts to arrive and see how much they will cost.
Also, there are a lot of lower-quality third party parts or even cheap and not reliable Chinese copies (Chinese stuff in our region is usually very low quality no matter what it is, starting from t-shirts and to trucks).
I was in the US twice and I found many good Chinese products which was surprising to me.

Thanks for being interested in our life here. Feel free to ask whatever.