cambob

My Toyotas are giving me a hell of a time lately. Ran out to pick up some parts for the 22re and my 3.0 4unner was leaking lots of coolant in the store parking lot. The reservoir was about 2/3 gone. Bought a bottle of coolant, filled it up drive home and let it sit for a bit, surprise no coolant loss. It looked like its coming out of the thermostat area where the wp meets the block. This isn't the first time it's had water leaks. I've been battling it since I bought it almost two years ago. After I did the water pump (twice) because I kept getting leaks I brought it to a mechanic who did it again. They got the wp sealed up good and then it sprouted leaks everywhere else. 90% of the coolant hoses are new now. The rad cap is good. It's not overheating, it runs fine, no smoke, oil/water clean, checked the plugs the other week (hg paranoia), but all I can think now is that coolant is over pressurizing somehow. Is there anything other than a bad headgasket that would cause this? Anything, please, lol

TNRabbit

If I read that right, you have coolant coming out near the thermostat housing? That would be the weep hole for the water pump, AFAIK.

Otherwise, I'd suspect a failing radiator cap.

cambob

The coolant is coming out right where the wp meets the block, in the area near the thermo housing. It is not coming out of the weep hole. The rad cap was just replaced (and tested to confirm its good) awhile back, Toyota cap. Seems like no matter what i do, another weak point is found and there's another leak.

vital22re

iTrader: (2)

A cracked head will allow compression to leak into the coolant.
If your motor over heats not to a complete boil over but gets hot enough it can search for the weak spot.

I'd make sure the fan clutch is good, radiator isn't clogged, and you've got good flow to the radiator.

Sometimes those blocks get pitted arond the water pump and do not seal well. I normally wire wheel the surface clean then apply a thin coat of rtv or FIPG depending on whats sitting on the bench. It could also be the studs for the thermostat part of waterpump aren't fully tightened into the block.

cambob

Since I've owned it, the temp gauge has never risen past the middle mark, but who knows if it did when the PO owned it. Tightened up the thermostat nuts as far as I felt they could without breaking and it seems to have stopped for now. No coolant loss yesterday. Just waiting for it to pop somewhere else. I'm pretty sure there is flow. One question about the fan clutch, I just read some thing on google that said it shouldn't spin at all until the engine is to operating temp. Is that true for the 3vze's fan clutch? And, it does spin right when you start the engine, so would it be needing replacement?

TNRabbit

Fan clutch spins at start until it warms up, then only spins when it's needed.

annoyingrob

I had this happen, couldn't figure out why I was leaking coolant out the hoses going to by heater core.

If you let the truck run for a few minutes with the rad cap off when COLD, if the coolant level rises and starts flowing out the top of the radiator, you have a problem.

cambob

Yeah so with rad cap off I get some bubbling. Not flowing out but it spits a bit out. And I know it doesn't need burping. These yotas are starting to tick me off. Got a 22re getting ready for rebuild and now this. Already buying a head for that engine. Would a head gasket cause it at all or is it more likely cracked head?

vital22re

iTrader: (2)

It could be a head gasket blown at the compression ring next to a water jacket. It really shouldn't bubble at the radiator if the system is full and has no leaks.There is a test kit you can buy that tests the coolant for exhaust gases. I would do that before a full tear down.

TNRabbit

Could be either/or.

I think your best bet is to do a cooling system pressure check. If you get pressure drop, listen for where it's going. TAKE ALL THE SPARK PLUGS OUT FIRST~

cambob

It actually passed a pressure test at my mechanics a few months ago. I'm gonna do another one though in case anything has changed. Thanks for the knowledge guys. Hopefully I'll get this sorted Out before winter, so I don't get desperate and pay my mech haha

Also those test kits for the exhaust, do they work pretty accurately? I've always wondering if they were worth buying.

abecedarian

To clarify a little:
If you start it with the rad cap off, you will likely get some surge in the radiator as the fluid expands and starts flowing- and this will happen a few times until the radiator itself is warmed up. After the thermostat has cycled as few times, there should be very little surging and absolutely no bubbles coming up in the radiator.

A dead give-away of a blown headgasket is a rainbow-like sheen floating on the coolant- that is either fuel or oil.

Leakdown testing will reveal any issues, even more than a cooling system pressure test will. The difference is during a cooling system test, the radiator and such are pressurized to around 16 PSI, but a leakdown test should pressurize cylinders to well over 100 PSI. So a simple cooling system test may not reveal a leak like the leakdown test will.

cambob

Thanks Abe for more info. I'm gonna go look at it again. I don't get any big bubbles (like the ones while burping it) it just slowly runs over the lip of the rad. So i was mistaken on a previous post. Doesnt seem to really bubble at all except right at start up i get one or two. So if I read right, say the engines at operating temp, I should have no coolant run over or very little? All my fluids are very clean, and that's usually how I see bad hg end up. I'm going to do a leak down to know for sure. Abe, to your knowledge are there any other ways the cooling system can over pressurize like this? My mech blamed it on a bad cap awhile back, which got replaced but it still acts up. It's weird how it won't leak for months, then bam, springs a leak.

Rinker

Hope you figure this out cambob. I'm searching for a cure before I make a post myself about similar issues. I hope members post some more info, because it seems like we're getting some where. Thanks to all for their knowledge and posting it! Good luck! Nothing worse than coolant issues.

cambob

Rinker, I really at this point have zero idea why it keeps busting hoses and seals. I can't find a mech to do a leakdown yet, they all do pressure tests which seems like it won't help me. I found a major leak between the intake and the throttle body and fixed that. For two days I haven't lost coolant. Maybe its just old hoses needing replacement and the cooling system finds the weak point every time. I've noticed every time a leak springs, its always on an old hose or seal, the new ones never start leaking again. Right now, thats the theory I'm working with.

kycreekrunner

put an o-ring on the thermostat make sure it is in the right way(will cause bubbling) and fipg the housing before you put it back on ....eaasy enough 3 studs

westjohns yota

sounds like your cooling system just needs an overhaul, bigger radiator might help, if its always old seals and hoses i guess just wait till everythings new, you said your radiator cap would overflow? thats not a good sign even though your not getting bubbles

Gareth68

As stated above, do a test for combustion gases. Any half decent mechanic should have a test kit. It only takes a few seconds.


http://www.amazon.com/UVIEW-560000-C...on+leak+tester

cambob

I know the thermostat is in correctly, new O-ring when I did it last year. It does not bubble through the cap, its when the cap is off, I get like just a couple bubbles and then it just slowly runs over the side. Doesn't bubble the whole time. It very well could be something like the rad. Its nearly 20 years old. Right now, its not leaking after fixing a hose, so its fallen down the priority list. I've got a 22re to rebuild and suck up my time And gas test, I didn't ask about, was more looking around for someone to do a leakdown. I may just buy one of the kits. Probably good to have with two older yotas around.

chuckr

iTrader: (1)

this sound alot like what my 22re(i know yours is a 3.0 but should act similar) did for awhile before the head gasket let go

if it is bubbling i thing your pump air past the gasket