dgz32

The temp needle headed north last night but never went into the red. I cranked the head and kept it moving and the needle would drop back to normal; heading north when we'd stop for a minute or two. So I parked it, and checked the coolant this morning. No coolant in the expansion tank, and the radiator took about half a gallon to get it above the fins. Not good.

I have all records for this vehicle, and know that the cooling system was serviced at the dealer in April of last year, approx 15k miles ago. I did not/have not so much as looked at the cooling system until this morning (insert idiot comment here). However, I've been under the vehicle many times since the purchase several months ago and the truck does not leak anything. The undercarriage is bone dry.

Anyway, it's obvious I'm loosing coolant somewhere; as much as a gallon (between the rad and exp tank) since it's last cooling system service early last year. What are the chances of it being the HG? I guess without a block test, it'd be hard to say? I don't smell any coolant in the exhaust, and see noting unusual in the color/consistency of the oil.

I called the dealer about the recall on the '96 and early '97s. The service guy ran my VIN and said that my vehicle is not under recall. Just to be sure, I've also contacted Toyota and expect a response early this week.

Any thoughts? Oh, 1997 4Runner 3.4L Auto w/140k

97ltd4x4

Besides the obvious under enging leaks..Check the trans dipstick for coolant mixing through the radiator/trans cooler...If you have rear heat check your rear heater core...under pass. front seat for leakage..



I highly doubt a headgasket,They very early 96' 5vz's had external leaks and would show up within 30k miles,manufacturing defect of the gasket...

If you cook the motor,well I guess anything is possible.

dgz32

I'll check the tranny dipstick tomorrow. Thanks for the suggestion. I don't have rear heat. Guess I'm a little paranoid coming from the 3slow. My '95 wasn't affected but HGs for those engines go at anytime. Most after 100k.

Motor seems fine and the truck appears very well maintained.

2000t4rAKS

Please keep me updated because I was cleaning the throttle body and MAF sensor and noticed that I my expansion tank was empty. So I filled the radiator and took a lot of coolant. I use the 50/50 mix from Toyota.
I am pretty good with maintenance with my rig and have not noticed any leaks coming from the undercarriage and do not smell coolant burning through the exhaust. There's just a small amount of water that drips out of the tail pipe but nothing out of the ordinary.

I will check the trans dipstick to see if coolant is mixing with the trans fluid.

How do you check to see if it is a head gasket? Expensive???

Adam F

Really? Ive never seen a 4Runner without rear heat. Especially a limited.

Can you take a pic of the area where it should be, behind the rear seats in the middle?

Ohio4R

I would check the transmission first, then check the thermostat and the sensor on the thermostat housing.

dgz32

I'll post back up to this thread if/when I find anything I will say I've had no issues at all since I topped everything off.


Best pic I have on me at the moment. I can take another tomorrow, if you like.




Checked the transmission dipstick. No issue best I could tell, nice and red.

SoCalPaul

Check the radiator for leaks, most likely where the tubes meet the tanks. You can leak quite a bit from there with very little ending up on the ground.

Paul

dgz32

Thanks for the suggestions, guys.

My overflow tank was a bit reddish this morning, but not frothy-scary-strawberry-milkshake-like. I'm presuming because I added generic green coolant to the Toyota red.

Also, does the strawberry milkshake really look like a strawberry milkshake...all frothy and delicious? Would it appear as such on the tranny dipstick?

hross14

Yes, it will look frothy and UMMMMmm delicious--do this

Borrow the a radiator pressure checker from a parts house. Then pump up the radiator system and have a couple beers.

Pull plugs also and let it sit for awhile. Look for pressure drops and at the end of the test if you dont see leaks--spin the motor with the starter and see if coolant comes out the holes.

It is going somewhere and sometimes it needs to be under pressure to start leaking-OR it leaks just enough that the motor heat...etc...hides the evidence.

Do this and you will know--then have another beer--i bet it is your water pump--you know the one where you have to pull apart the front of the motor and redo the timing belt!!!!!

AND use the right coolant--

dgz32

Thanks, sir. I try to give this a whirl over the weekend. I'd like to do a full cooling system flush; and honestly I really need to spend some time going over the vehicle anyway. Tranny and diff fluids, plugs, wires, filters, ect. Also have a couple of stubborn grease fittings that I'll probably end up replacing as well. Good times.

The right coolant? I'm presuming you're referring to the Toyota branded variety? Surely that's not the only 'right' coolant out there. My owner's manual states that any type of ethylene-glycol coolant will do in 50% solution. Of course if the Toyota stuff is really better, then I'll certainly pick some up. Seriously, what's the advantage??

dgz32

Little update. After warming up the truck this morning and backing up, I find a ample sized pool of coolant on the driveway. Leaking just behind the radiator on the far right. Still had coolant in the expansion tank after idling for 15 minutes, though. Looks like I'll def be ripping into this tomorrow.

mjwalfredo

I think that's good news that it is not the water pump right? heh.

I don't think they started adding rear heat until 99'. My 97' limited does not have rear heat and my buddies' 98 SR5 does not either.

4Runner202020

thats not true. my 96 has rear heat...

hross14

that is really good news--if i remeber correctly--toyota brand antifreeze has is some what different from the others and really does last the extended time needed.

Google it--but it had something to do with electrolysis ..e.tc... protection.

I could be wrong--but check it out

dgz32

LOL! Its funny when a leaking radiator is good news

And, interesting about the Toyota stuff. I'll look into it.

dgz32

Just for kicks, I called my local dealer and asked what a water pump install (w/timing and drive belts) would cost. Said it be right at $730 w/tax. And they'd give me a rental...

Think I'm gonna be doing this myself. I've looked at the procedure and I can't see it being be any worse than the overhaul I did on our BMW 540. I just need to source that fancy tensioner tool.

hross14

is it time for the timing belt to be replaced?

dgz32

Yeah, I could stand to change it...might as well with the WP going in. I've priced everything out at toyotapartsales.com and with the discount I can get almost everything I need for under $200 shipped. Timing belt, upper/lower rad hoses, WP, drive belts, and thermostat. I guess I need the crank crank pulley nut, too...and coolant (Toyota red ). I have a 250lb torque wrench, but will have to make the deal that holds the pulley. Oh, and I found the TB tensioner at Amazon for $28.99. Score!

96runner4x4

maybe its the thermostat. same thing happened to me. i had the timing belt done on my truck along with everything else and after that, the thermostat housing gave out for some reason. i was 200 miles away from home thinking i had a leaky water pump but it wasn't. whenever i would drive, it wouldn't leak as much, but when i parked overnight, i would find a puddle underneath my truck. not realizing i had a leak, i saw the needle head up north towards the red zone.i had to fill up the radiator every time i started the truck after it was parked overnight. luckily for me it was a small enough leak to where i drove it home and made it.