heater control valve failed (pic's)

[tyr0981]

So myself my brother and another friend where getting together for a day hike, we stopped at our friends place so they could get their backpack together, we're standing around the front of the 4runner BS'ing and suddenly there's the distinct sound of pressure releasing and steam coming from under my hood! :shocked: :nono: !!! if this had happened ~15min latter i'd been on the freeway traveling nearly 100 miles away from civilization / help!

i'm VERY concerned about the condition of the internals now, i've never seen any rust, never seen serious corrosion on any parts (except this poor heater control valve).... the previous owner was a piece of shit though, he neglected the 4runner in unbelievable ways, but i've been taking care of her for the past 11 years, now running Toyota Red coolant drained and flushed out with DI water last summer. Was this just bound to happen eventually, or should i start taking stuff apart and replacing other items before i get stranded somewhere besides my friends driveway? thanks for your input peoples!

 

[gamefreakgc]

Hoses don't last forever, same with belts. I'd check over all rubber components. If any show any sort of cracking, splitting, or leaking replace them. It's rubber that's between 15-20 years old so it will fail eventually. Makes me wonder though, do you know the last time you had the timing belt done though?

Same goes with bushings used on the sway bars and other suspension parts. If damaged or cracked it's time for new ones.

 

[tyr0981]

Hoses don't last forever, same with belts. I'd check over all rubber components. If any show any sort of cracking, splitting, or leaking replace them. It's rubber that's between 15-20 years old so it will fail eventually. Makes me wonder though, do you know the last time you had the timing belt done though?

Same goes with bushings used on the sway bars and other suspension parts. If damaged or cracked it's time for new ones.

yeah i replaced the timing belt 3 year ago, it looked fine but it was about 10k overdue at the time so that's covered for a bit longer, i guess i should look for the stuff at the end of the hoses to be coming out of there (no idea what it's called) that was the only outward sign that something inside wasn't right... and i defiantly need to replace the tie rod ends.

 

[gamefreakgc]

This is by no means a "scientific" approach but I've noticed that before coolant hoses fail they tend to seep out small amounts of coolant which will build up a crust at the end of the hose. If you see than then it's a warning sign that either the hose is too loose and leaking, or the rubber is breaking down and it will fail at some point.

 

[85straight]

A good sign of a hose going bad, it will a bit swollen on the end

 

[tyr0981]

This is by no means a "scientific" approach but I've noticed that before coolant hoses fail they tend to seep out small amounts of coolant which will build up a crust at the end of the hose. If you see than then it's a warning sign that either the hose is too loose and leaking, or the rubber is breaking down and it will fail at some point.

yeah that's what i was trying to describe, that was the only "warning sign" i could find when i replaced the control valve, mind you these hoses are 5/8" and tucked way back against the firewall behind the intake manifold, so they're very out of line of sight, at least they where, i certainly know about them now....

 

[gamefreakgc]

Just be glad it's accessible. The 2nd Gens had a U-shaped coolant hose on the back of the engine and it had a problem of bursting. Happened on mine and my brothers and many others.

In some cases the motor had to be pulled just to replace the silly hose! Let's just say the 5VZ-FE engine is MUCH better in design than the 3VZ-E.

 

[tyr0981]

Just be glad it's accessible. The 2nd Gens had a U-shaped coolant hose on the back of the engine and it had a problem of bursting. Happened on mine and my brothers and many others.

In some cases the motor had to be pulled just to replace the silly hose! Let's just say the 5VZ-FE engine is MUCH better in design than the 3VZ-E.

agreed, it could have been much worse, especially if i was off in BFE.


The hose did NOT fail, the hose looks fine in fact, the plastic control valve is what rotted away, I've never heard / read about that happening before....

 

[LittleCaesar]

Not the first time one has leaked on this forum, but never quite the clean break you had.

Replace it, maybe the hoses as well and drive on.

 

[the great him]

mine basically did the same thing... except it broke when i tried to change the hose... it was pretty rotten.

 

[StreetCreeper]

Just be glad it's accessible. The 2nd Gens had a U-shaped coolant hose on the back of the engine and it had a problem of bursting. Happened on mine and my brothers and many others.

In some cases the motor had to be pulled just to replace the silly hose! Let's just say the 5VZ-FE engine is MUCH better in design than the 3VZ-E.

Oh man that would piss me off to no end! I would probably push it off a cliff just as a matter of principle........and then promptly kick myself for my ridiculous knee-jerk reaction to a little adversity...

 

[gamefreakgc]

Oh man that would piss me off to no end! I would probably push it off a cliff just as a matter of principle........and then promptly kick myself for my ridiculous knee-jerk reaction to a little adversity...

I loved the truck since it was indestructible but that engine was terrible to work on. I don't miss it at all.

To OP: So it was the valve? Oh, that's odd. Usually hoses fail first. I think you might be ok with hoses but check them anyway. Getting stranded is not fun, especially when you are sick with salmonella on the way back from the hospital.

 

[pluton]

Is this an actual Toyota valve....it looks different somehow?

[/QUOTE]

 

[tyr0981]

Well okay, i'll poke around and make sure there's no more 'crusty' hoses on her... the heater core attachments looked fine, little bit dirty, but nothing bad, i replaced the radiator hoses 2 years ago with the new radiator... just have to keep my eyes peeled i guess.

Is this an actual Toyota valve....it looks different somehow?

The OEM one i replaced it with from the Toyota dealer down the street looks exactly like this one, both say Toyota on them. I think they're the same....

 

[mkeomotupp]

It's rubber that's between 15-20 years old so it will fail eventually.

 

[eatmorechickenx]

AHAAHAHAH. Mine just did the same thing last Saturday. Except, the nipple broke off about half way, so I smothered it in permatex and stuck the hose back on it and clamped it (piece of nipple still in the hose). Note: Not the proper way to fix things unless your very comfortable with fixing things on the side of the road and always carry the necessary supplies to do so. I'll probably repair it properly this weekend.

 

[tyr0981]

It's rubber that's between 15-20 years old so it will fail eventually.

it is NOT rubber.

 

[eatmorechickenx]

it is NOT rubber.

Its not, your correct, just old brittle plastic.

 

[tyr0981]

AHAAHAHAH. Mine just did the same thing last Saturday. Except, the nipple broke off about half way, so I smothered it in permatex and stuck the hose back on it and clamped it (piece of nipple still in the hose). Note: Not the proper way to fix things unless your very comfortable with fixing things on the side of the road and always carry the necessary supplies to do so. I'll probably repair it properly this weekend.

i was thinking about doing that also! but there was no lip left on mine, so i had to bypass the heater core & back seat heater also... thankfully it all worked out until the next day when the part came in.

 

[BamaDrewski]

I just did some preventative maintenance on the heater/AC system a few months ago when I replaced the AC servo on the passenger side. Part of the PM was replacing this heater control valve (Bought mine from Amazon - "FourSeasons" brand.)

One other tip - the cable that controls that valve can get corroded and stick in the plastic sleeve it fits in. I took a syringe and filled it with liquid teflon lubricant and injected it down between the cable and the plastic sheath it slides in. (The gap is so small, only a syringe needle could get in there and force the lubricant down the sheath)

Now everything works smooth as silk.