James Owens

Hey all,

New to car's here, but recently I got a 86 4runner SR5. I has had much of its engine rebuilt, but the body has over 255,000 on it. I recently had to replace the alternator on it and while doing so the power-streaming line ripped (drawing it), which I fixed and refilled, and I had to remove the coolant line on the bottom diver-side of the radiator, thereby draining the radiator. I replaced the alternator, put the line back, filled back up with coolant, and everything was okay. However, now I am having overheating issues, there is a small aluminum lever next the coolant line on the bottom driver side of the radiator housing unit, and I tried turning it to keep the radiator from fully draining originally, but it didn't seem to help, now, however, the metal is so old and soft, that it just bends when I try to turn it back to where I think i was supposed to be. Furthermore, the vehicle has some trouble cold starting, it take a couple of try's to get it going and I have to do a bunch of weird stuff to get it going (which wasn't happening before).

What I am wondering here is what some of my problems could be and potential solutions. The waterpump was just replaced so I don't think it is that. There aren't any coolant leaks, so I don't know. Any thoughts?

RAD4Runner

What lever?
A picture paints a thousand words. Pls see signature.

Please put us at your truck and let us know what yo see, hear, feel.
Trouble cold starting as in starter not cranking OR starter cranking but not getting combustion (when you hear, feel the "Vroom", see and smell smoke)?

James Owens

Hey all, sorry for the late response.

Here is the picture of the lever you wanted, on second review, I am pretty sure it is not an issue and didn't alter anything about the flow of coolant, I don't even think I was able to turn it originally.



Furthermore, I have been reviewing the vehicle more closely and on second look much of my original post don't seem to be an issue. I the car is starting up fine, so that is not an issue and I don't think ever was. However, it still is overheating. If I drive the vehicle for more than 10min. and reach speeds over 30mph, the thermometer dial on the dash registers the engine as running very hot. If I push it close to over 50mph for more than a minute, the dial pops up to the danger red zone, however, if i drop down into lower gears, and keep it under 30mph, the dial will drop back down to the midway point. After stoping the car, visible steam can be seen rising form the radiator out from under the hood. The coolant seems to be flowing, but not working to cool the engine, as it seem to be dumping into the radiator boiling hot.

Thank you.

5 Fists

I don't think that's a lever, I believe it's a Transmission cooler line connection.

I would look at the thermostat, even remove it and test it in a pot of water to see if it's working properly.

What brand of water pump was put in? I've heard of cheaper ones being defective from the get go, though I don't know how common that is.

When I was fighting an over heating issue, it ended up being a physical block in my radiator, which I could only see after removing the rad, there was a dark spot in one of the bottom corners that was not visible while mounted.

James Owens

If it was not connected to anything when I got the car, and it the car ran fine when I got it, until now, does it have a function that it currently is not performing that it should be?

5 Fists

I believe they are only used for Automatic transmission, though I could be wrong. Do you have an Auto or Manual?

Also, I edited my above post with a few more thoughts.

James Owens

In regards to the work I previously did on the car, which option do you think is most likely to be the issue?

Also, it is a manual.

old87yota

The thing that you referred to as the "lever" is for the built-in automatic transmission fluid cooler in the radiator.

Since your Truck has a manual transmission, that pipe is not used (there should also be another one on the other side of the radiator, but probably bent differently; that pipe is also not used).

James Owens

Oh, sorry, I meant in reference to the original issue's I was having, the original post, which was about repelling the alternator and then having the engine over heat after that.

James Owens

Update:

I tested the thermometer, it opens just fine. Another issue has arisen though, there is a wire and bolt on the top of the housing compartment for the thermometer which looks to have shorted and broke. It is not in the manual and not on online videos about repacking the thermometer. What is it, what does it do?

picture below.

James Owens

Also, I just did a test for air in the coolant lines/systems and made sure to get all the air out/run the engine up to operating temp. What I found is that while the upper radiator hose gets up to temp, as expected, the lower one, on the bottom driver side, which can be seen in the photo above (the photo about the lever earlier on), does not change in tempt to match that of the upper radiator hoes.

5 Fists

I believe that is the Temperature Switch that sends a signal to the ECU.

RAD4Runner

Did you look to see where the steam is coming from?
Please let us put us at your truck if you want us to help. Tell us what you see, hear, feel, smell.
When was the last time you flushed the cooling system?
Observe how your fan clutch aka liquid coupling and compare to what I saw on mine HERE.

There you go. Pics are nice. It makes us see from afar what you are dealing with.
It's the coolant thermo switch (ecu-tsw input). I refurbished mine HERE I don't think it affects cooling system temp.
It goes on TSW input of ECU. HERE

Do you mean to say that's what you used to drain the radiator? So that's the radiator drain cock.