Hi all, just a quick intro for me ... I'm from Brisbane, Australia and I just bought a 1992 Toyota 4Runner SR5 Limited, 3.0L V6 3VZ-E, auto. I've has a Surf before and cooked the engine before reading a lot about the Surf 2.4L TD engine not being really great in Australian heat. Yay for me.

Now I'm back with a 4Runner as these are built here rather than the Surf being imported from Japan so I figured I'd have better luck. A little distressing to me was after my first highway drive and I noticed steam from under the bonnet, bubbling in the overflow tank and water dripping from under the vehicle. The water is a little greasy, either oil or coolant I'm guessing. Note that the temperature gauge sits nicely under half way.

I've been doing a lot of reading and notice the head gasket is a common fault on these guys. I've called my local Toyota dealer and there is no recall or 'special service campaign' currently on this vehicle which I've read a lot from US owners.

So I'm back to doing some troubleshooting of my own. What should I do first?

check thermostat?
check coolant temperature sensor?
CO2 test?
pressure test?
something with the fan?

Some info that might help is that the fan is going as soon as I start the engine - I'm not sure if its supposed to do that or if its overworking or indicates a sensor is faulty? Speaking of which, the guy I bought it off said the temp gauge wasn't working for a while and had to clean the sensor connections. could this have something to do with it?

After losing a f&%# tonne of money on the Surf when it overheated, I sure as hell don't want to have a repeat with the 4Runner after specifically getting the petrol to avoid that issue.

Any feedback would be great so I can get this sorted before I start taking it on beach camping trips etc. (oh look ... pretty smilies )

Thanks.

 

bubbling overflow while running = bad head gasket. if you do this from a cold start i can pretty much guarentee thats the problem.

 

x2

Perform a leak down test if you can. GL

 

Good day to you. Well four startars mate, welcome to yotatech.


1. Whats a "bonnet"?
2. Replace your radiator cap (its a cheap start and it might be your only problem)

Bubbling from down under your bonnet doesnt always mean catastrophic failure like mentioned above.

 

you would be correct. start the vehicle without the cap on and see if there are bubbles in the radiator while its running. if it does, headgasket.

 

Apparently a "bonnet" is also referred to as a "hood" in some parts of the world.

Thanks for the quick responses everyone, I'll run down to Repco tonight and see if they have a radiator cap I can swap over. A couple of questions.
1. Do I need a specific radiator cap or will any do?
2. Should I get a mechanic to do a leak down test? I'm not overly mechanical (I.T. guy here).

Cheers,

 

You need the specific radiator cap for your ride.

If you aren't familiar with a leakdown test... yes, have someone who knows what it is perform it.

Basically, a leakdown test involves putting the piston at top-dead center of the compression stroke, putting a fitting where the spark plug goes and filling the cylinder with high-pressure air. If bubbles appear in the radiator, either the headgasket is bad or the head or cylinder is cracked and is letting the air get into the cooling passages.
It can also tell you if you have bad intake or exhaust valves and even bad piston rings.

 

1. Check for white smoke from exhaust.
2. Disable fuel, remove spark plugs, (if you have coolant pressure tester pressurize system if not test should still work), look for coolant in cylenders, crank engine and look for coolant shooting from spark plug holes.

 

Mu truck (22re) had some greasey coolent also. Mostly seen on the radiator tap. Turns out that one of the water jacket on the bottom of the head was corroded all the way to the closes piston (cylinder). I did have high pressure and over flowing in my resurvior. Cylinder head went bad. Hopefully yours os still good. Might just be a head gasket.

 

White smoke in the exhaust is not a guarantee there is a cooling system breech- they can happen without any visual indication other than an unexplainable loss of coolant.

Considering the cooling system may operate at upwards of 16 PSI (may be more or less depending on the system), and the cylinders operate with compression exceeding 150 PSI- several times higher than the cooling system pressure, a small coolant leak will not necessarily be evident by simply pressurizing the cooling system. Matter-of-fact though, pressurizing the cooling system above it's rating will damage it.

On the other end of things, gasket breeches and such will be obvious when over 100 PSI is presented from the other side of the gasket,(more than 5 times what the cooling system produces), and such tests will not damage an otherwise intact cooling system.

Having the coolant tested for hydrocarbons may similarly give up the ghost.

 

Damn, just wrote this novel and forum asks me to sign in again ... all gone. OK, here's the guts of it.

Radiator cap looks fine.
Filled about 2L of water in the radiator; loss explains steam and wetness of the undercarriage.
Good news, no air bubbles while running after filling back to full. Good yeah?
Brownish gunk in water - could be old red coolant? not sure.
Still get bubbling/gurgling noise, almost from start up
Never gets past half temp on the gauge but gets there very quickly and engine bay heats up quickly.

End result: going to get mechanic to do a general look over it and give me a run down. Will post back when I know more.

Thanks for everyone's input to date. Very helpful and assuming the Runner stays drivable, I'll be back here again I'm sure.

 

Check the coolant bypass hose (upside down U just under the edge of the plenum) next to the firewall, passenger side while the engine is revved up. Common hose failure. That can give you wetness below, as can an oil cooler hose.

 

Wow, daylight really helps. Turns out the coolant is the normal green stuff so now I'm a bit unsure about the brown gunk. I thought it was maybe oil from a busted head gasket (man, head gasket seems to be the underlying problem of everything I read on this forum) but I found a post with some pics and they look different to mine.
So here's some pics. If anyone has further input, would love to hear it. Thanks again.

 

Looks like the left overs of a very neglected cooling system that was recently re-filled with green and they forgot to clean out the overflow tank.....

or....

it's oil that was mixed with coolant from a HG issue and the seller masked the problem with new coolant and some HG sealer magic elixer. Hmmmm.....

 

if oil was mixing with your coolant it wouldnt be green, and your oil wouldnt be brown/black. check your oil.

 

Leanin that way also.

 

Maybe the transmission cooler hose has a small leak?

 

OK, so I'm leaning towards doing a full cooling system flush on the weekend, refill and observe. I'll also degrease the engine and undercarriage so I can see if the liquid I've seen down there is new.

I've never done a cooling system flush myself before but from what I've read, it shouldn't be that hard. About time I learned to maintain my own truck rather than forking out $$$ for someone else to do it.

I've read mixed opinions about green vs red coolant. Is there any definitive answer?

Will post back after the weekend.

 

Most use red, some use green. It's important to fully flush and refill the cooling system every couple of years.

Be sure to use distilled water. There are threads around here about how to flush and burp the system.

 

check the oil first to see if the head gasket went