JaredL

85 4runner 22re automatic

The last couple of days, the coolant in my 4runner drains into the reservoir and then pours out the overflow hose leaving the fins exposed in the radiator. I replaced the thermostat recently with a genuine Toyota and I ordered a new radiator cap from Toyota....hopefully that will fix the problem. Any thoughts?

Some other things to consider:

* No white smoke
* No power loss
* Oil looks good--no white gunk on the threads of the cap
* Heater works great
* I tried burping the system but coolant spills out the radiator as soon as it gets to operating temperature so I can't squeeze the upper radiator hose for too long.
* Reservoir cap is a little loose...could that cause a problem?
* Engine temp gauge gets a little high (not to red line but right below) and then goes down to normal after a few minutes of driving. Does this mean the coolant is getting pumped back into the radiator from the reservoir?
* Possibly a bad water pump?


Thanks for any suggestions. I'll post back regarding the radiator cap and if that helps any.

Thanks,
JARED

Bingle

Had this same problem a few years back, was bad head gasket. Was a small hole between the cylinder wall and one of the coolant passages right next to it. For whatever reason I wasn't getting coolant coming back into the cylinder, but when running it was pushing gasses into the cooling system.

Hopefully this isn't it but it's something to put on your "to check" list. Maybe something like a leak down test with the rad cap off to watch for bubbles and/or coolant overflowing.

Good luck.

JaredL

That's depressing. Wouldn't I have white smoke in exhaust? The issue isn't always occurring either. Today, for example, everything seems to be fine and the fluid isn't pouring back into the reservoir. Thanks again for your insight. I just hope this isn't the case as I just got this engine rebuilt not too long ago.

osv

was it overfilled to begin with? you want to leave room for air in the radiator.

something sure sounds weird tho.

the right thermostat is supposed to be the one with two holes in it??

really good idea to replace the cap.

i think that the coolant is supposed to get sucked back into the radiator as the engine cools off, so the radiator cap plays a role in that.

don't like the temp gauge reading, did it do that with the previous engine?

i think that you can get a test kit that checks for exhaust gasses in the cooling system.

JaredL

Thanks OSV. So I guess it has been a little longer since the engine was rebuilt although not that many miles (9 years--20k miles). I was just hoping the headgasket would have lasted a little longer. At this point, though, I am thinking radiator cap instead of HG. Here's why: I pulled all plugs and they all look evenly dirty. I checked the oil and no milkiness on the dipstick or cap. I did notice little black (1/4 inch wide) paper-thick floaties at the top of the radiator near the cap. In fact, they were collected on the cap. I fished those out and cleaned the cap. Here's the best reason why i think it is the cap. With the cap on top and the engine cool, I squeeze the upper radiator hose and coolant flows out to the reservoir. On my other 22re (93 4x4), when I squeeze the upper hose, nothing gets past the cap. So, my theory is that if the cap is letting coolant past when cool, therein lies my problem as the vacuum that is supposed to being made is not occurring. Could I be right? I am getting a new cap tomorrow, so we'll see. Still not ruling out HG, just hoping it is something simple. Thanks again and I'll post back as soon as I find out something.

osv

that definitely sounds like the cap is shot.

doesn't explain the high temp at warmup tho, my 22re never approaches hot at all, if it's near the halfway mark i'm panicking.

Bingle

Here's hoping it's the cap. Would definitely change that first.

My head gasket leak was a weird one, I wasn't getting any coolant or oil in the combustion chamber and I wasn't mixing oil and coolant, was just getting combustion gasses in the cooling system. Mine would suck some of the coolant back out of the reservoir when it cooled down, but not nearly enough. That was my oddball/non-standard HG failure.

Simple/cheap fixes first, because 90% of the time that's what it is.

Obmi

When mine started acting up ( Wife came home saying the truck sounded like a coffee percolator) I know bad thing were coming. this was around 2000. I put some copper seal up in the radiator and it ran ok for about 15 years. Now its really bad, truck sounds like a lawnmower ,7psi on cylinder 3. So now it head gasket time. Oil is clean and sous not use radiator fluid but does blow it out like your having. for a long time i put a 2ltr soda bottle on the over flow hose and once in a while I would pore it back in.

JaredL

Update on this issue. So I took the 4runner to a mechanic (reputable) and he did a compression test. aside from the #2 cylinder having tight valves and a clogged radiator, he said the compression was good and to have the radiator cleaned out and I should be good.

So I set the valve clearance (sure enough #2 was way too tight) and that helped with the erratic idle. It runs smooth now. I also got my radiator professionally cleaned. Slapped it all back together and the coolant is still not flowing back from the overflow tank and it is going onto the ground.

I did more searching and found that the iiav hose was leaking and had a crack. Replaced that with a new one. I ran a radiator compression check. it held at 14psi for 15 minutes without issue. Then I read online to check the coolant reservoir cap to make sure it is not on backwards. It was backwards and I fixed that. Not sure why that would matter.

After doing all this, today I drove it and it does not overheat and coolant does not spill out but the temp gauge reads about 3/4 high right after restarting it from normal operating temperature and then after driving a mile or so, the temp goes back to normal. Again, the gauge does not hit red.

I bought a new water pump....was thinking that could help but I havent installed it yet for fear that if I have to redo the headgasket, I would be taking the water pump off.

So, I know the majority of these overheating issues....most people point to the headgasket and I would replace this if I knew for sure this was it. But I am not seeing any symptoms of a bl0wn headgasket and a mechanic has said the same thing. Should I try blockchek just to be sure? Anybody use this?
http://www.blockchek.com/

Thanks again. I hope to nail this down soon.

JaredL

Oh, and I did get a new Toyota radiator cap. Didn't seem to help the issue.

osv

overheating is when the temp doesn't drop back to normal after driving it a mile, it gets hot and stays hot.

did you put in the two-way toyota thermostat that's supposed to stop the brief hot temp? i put one in my 22re just a few weeks ago, the old thermostat was stuck open.

JaredL

Hey OSV. I put in a genuine Toyota thermostat (from dealership) but I don't know if it is 2-way? Is there a part # I can reference? Our dealership parts dept has a habit of getting me the right part for the wrong year and I wonder if maybe this is a later model thermostat.


Thanks,
JARED

thefishguy77

iTrader: (1)

Mine was doing the same thing. I did the cap and thermostat from Toyota. Put a new radiator in I had laying around. Then finally couldn't keep it cool at all. Compression was good and oil was good sometimes it just goes. Sucks. Hope it's not a gasket but prepare for the worst and that way you you don't get blindsided.

osv

i still have the box laying around, it's a 90916-03070, here is a relevant thread: https://www.yotatech.com/forums/f116...issues-132015/

sounds like the only problem left is the brief temp overshoot? nothing else is wrong?

JaredL

SOLVED -- I Think

So after nearly getting the HG kit for this, my dad told me to replace my thermostat. I thought this wasn't going to work as I had bought a Toyota one 6 months prior. Sure enough, replacing the thermostat did the trick. Toyota graciously provided a new one at no cost.

I haven't driven in 4x4 yet, but the temp stays consistently at 1/3 and coolant no longer boils out of the reservoir. Pretty happy camper at the moment.