Radiator flush problems

[mgcorreia]

I got a 1997 4runner with 207k miles, 4cyl. I've only had the car for a few months and its my first toyota.

Last weekend I did a radiator flush. A few days later after the flush there was a couple of times my car was about to overheat, which prompted me to pop the hood and see what was going on. I found the coolant level was low, so I added some more to the radiator and brought the expansion tank to the full mark again. I then drove it to the store and when I got there I found steam coming out of the expansion tank and the coolant bubbling inside of it. You could also feel the coolant bubbling around in the radiator hose. When I drove back the car was fine however. What went wrong? The car drove fine before I did the flush. Also when I drove the car back I found my expansion tank empty once again. Should my expansion tank always be at the full mark? thanks

 

[jeff88]

Can you clarify what exactly you did? Did you drain and fill? Did you run straight water in it after draining it? Did you run a flush cleaner after draining it?

I don't want to rush to conclusions, but there is a chance that you found a leak. It can happen after doing a flush, but as crappy as it is, it's better to find it now, rather than on a road trip. Go to the auto store and rent a radiator pressure test kit (it's a bike pump connected to a hose with a radiator cap and a gauge). If there is a leak, you will probably not even get to full rated PSI before the water started escaping wherever the hole is. (It might be a slow leak, it might come out something close to steam.) I've diagnosed/fixed 2 cars in the last year using this method; cheapest, easiest, fastest way to figure out exactly what's going on.

 

[mgcorreia]

Here is what I did...first I unscrewed the plastic thing on the radiator and drained it. Then I turned the heater up and ran the car to open the thermostat while pouring hose water through the radiator until it came out clear and clean. I screwed the plastic piece back on, filled the radiator and expansion tank up, turned the car on with the heater again until the coolant flowed out of the radiator to bleed the system and that was it. Immediately after I drove it first time after doing this you could hear the coolant sloshing in the radiator hose.

 

[hoe_nah]

park it on a hill nose up. run the truck n let the system burp. probably got air trapped in the system

 

[kball]

Make sure the rad cap is on all the way. Sounds like you're not building pressure if it's boiling that easily.

 

[Mr.4runner]

I had a similar issue a few months back. And in my case it ended up being the radiator was clogged and didn't let a ought coolant though. Once I replaced the radiator it took care of it.

If you put your hand over the radiator once the engine gets up to operating temp and it's not hot then u have the same issue I did.