Coolant boiling!

[lxsirprize]

Another question for you all. The last time I drove my car started blowing steam. Specifically, once I got home and checked under the hood, I found coolant spitting from the radiator cap and the fluid was boiling in the reservoir. I haven't checked the thermostat yet.

You think this is the issue? My thermostat stuck closed?

Anyone else had this issue? I tried searching the forum, but I didn't get any hits.

Thanks all!

 

[toyolla86]

i would say if your radiator cap was spitting you should try and replace that first. good indication that its not sealing and thus its letting coolant out and your coolant gets so low that you overheat.

cheapest route, replace the radiator cap (refill the radiator and res). then if that doesnt work go with thermostat.

after you fill the radiator (before putting the radiator cap back on) start the car and watch the coolant in the radiator. is it bubbling still after the initial start up. like 1-2 minutes in with heater on full blast. you may have a leak somewhere else... like head gasket. also look under the car. is it visibly leaking anywhere? does it smell inside the car? if so theres your leak. if not it may be getting into the cylinder from the head gasket. but dont go jumping to conclusions. first do the easy stuff and then jump to big conclusions.

 

[mkIIIman089]

Start with the obvious - replacing the radiator cap. In addition to that since there is loads of air in the system anyway I'd replace the thermostat as well; I don't know what the ambient temp in WV is this time of year but for it to be boiling so aggressively seems unusual even assuming the system isn't retaining any pressure. (BTW the coolant in the overflow probably wasn't boiling, just bubbling from the venting radiator.)

Beyond that, even if it wasn't the cause of it the head gasket is likely trashed from the heat.

 

[toyolla86]

that sucks. just cause it overheated once the head gaskets are trash one these. is that just if its an oem 20 year old head gasket or do the newly replaced metal ones also fall under this blanket mkiii problem.

 

[mkIIIman089]

My .02: They slowly deform over the lifetime of the car, then another 20 year old part fails in the cooling system and that resultant overheating finishes it off to the point where symptoms are detectable. A new gasket, Toyota or metal, with ARP studs will likely solve the issue permanently as long as water temp/level is kept in check.

For perspective, many much newer, much lower stressed engines also have proven to have loads of head gasket problems. Only recently my sister's Sentra had to be scrapped because of a BHG that destroyed the engine @ 70k miles.

 

[lxsirprize]

Wow! Thx all. I'll get a new radiator cap this week and replace that and the thermostat.

The temp is about 40* here this time of year. Didn't expect this many issues with this car. I found it and figured I got a great deal $1500, but I guess I know why now LOL

Either way, this is still my favorite car and I'll get her on the road! I really appreciate the advice from each of you!

 

[DuckieTom]

Hey this happens to me not so long ago. It wasn't long later that my head gasket took a dump. Do a compression test to see if there is a minor leak. Anyhow, I stupidly replaced the head gasket - Toyota Brand and everything worked fine afterwards. However, I should of went with the metal HG. Hope that helps and goodluck to you

 

[SRZMK3]

FOR THE LOVE OF GOD CHECK THE OIL TO SEE IF ITS MILKY!!! IF IT IS PARK IT NOW!!!! you dont want what happened to me. every time i read these head gasket issues it gives me anxiety that the supra owner is gonna neglect to fix it and keep driving it. if the oil is milky and you keep driving it say bye bye to the whole engine crank bearing sammich yum yum. the water in the oil wont give you enough viscosity and your bearing will be eaten alive QUICKLY!!!

 

[bioskyline]

the rubber gasket in the rad cap goes, but if it really boils its bhg, as your filling the cooling system with compression from the cylinder, my 4ag did that.

 

[lxsirprize]

Thanks again everyone! I checked the oil...still looks good; not milky or "weird" in any way. I put a new radiator cap and flushed the system and refilled....so far so good. It is about 30F here, so I don't know if that is keeping the temp down or not. I'll check it again in a few days. I only run her on short 5 minutes trips for now until I can trust taking it to work and back. Other than some of the other signs noted about BHG, is there any other way to know if thats going out?

 

[IJ.]

Go to Napa buy a test combustion gases kit read the destructions and use it.

Don't "guess" don't listen to opinions do the test and find out for sure.

 

[Devin LeBlanc]

X2 ^^^ Don't do guess work because you'll just do more damage if you wait and keep driving it. Gotta diagnose the problem to fix it

 

[mkIIIman089]

Go to Napa buy a test combustion gases kit read the destructions and use it.

Don't "guess" don't listen to opinions do the test and find out for sure.

These aren't always as definitive as many would have you believe. In my case it didn't do anything but place more doubt whether or not the head gasket was beginning to fail. A collection of extremely mild symptoms were the only indication, and it was in fact failing.

 

[IJ.]

These aren't always as definitive as many would have you believe. In my case it didn't do anything but place more doubt whether or not the head gasket was beginning to fail. A collection of extremely mild symptoms were the only indication, and it was in fact failing.

They're better than asking forum people for opinions....

 

[mkIIIman089]

Sure I agree, I'm just saying it may not be a decisive "pass/fail".

 

[hvyman]

You need the car to be hot and run the car for little while with the cap off so you get smoke for it to be effective. They work especially the 2 chambered ones. Compression leak down and pressure checks also work.