Can Overheating Be Linked To Overflow Res
 

My overflow reservoir has a leak. I attempted to fix it on the weekend but it started to rain and I realized there was more than one bolt holding it on like I thought, so I figured it could wait till this weekend. I usually had to add coolant every two days but I ran out and for the past two days have been running with the overflow dry. Toyota wants 105 US dollars for this stupid little item and I'll be damned if I pay that for what amounts to a plastic soda bottle. Anyways, today I overheated after a short run (maybe two miles). I let it cool down and drove it back home slowly with the hood popped and the heater blowing. So I got home and sure enough I was low on coolant in the radiator (which has never happend before) but I saw no leaks. I filled the radiator and the res and ran the car a little and everything seemed to work fine and still I saw no leaks under the car. Can this little reservoir cause such a headache? I left the car in the driveway and took the bus, but I plan on taking it off and using some kind of epoxy on it. What I'd like to know is, should I be looking some where else for leaks, or can the reservoir be the totality of my problem? I love this car and it usually runs like new but I'm having some little thing drive me nuts every other week lately.

Thanks

James in NJ

the res is supposed to overflow if it has too much in it. are you sure it has a leak/hole in it? mine did this also but it was only because of a bad thermostat

Re: Overflow
 

Yeah, it leaks. I fill to the halfway point like it says, put cap on nice and secure so no evap, and in two days its drained. As its winter here, I cant just use water, and its getting expensive using all this coolant. What would happen if I pinched off the hose, would it fool the sensor?

James in NJ

i'd say your engine is using the water instead of it's leaking out of the bottle .
unless you actually see water coming out of the bottle it's not the bottle it's the cooling system .

It sounds like your engine is sucking it into a cylinder and burning it off. Do you smell antifreeze at the tailpipe?? How's the oil? Milky brown?? Over full??

Re: Coolant Leak
 

Yeah, I'm leaking coolant. It's not overflow res. Problem is, I leave for work, its dark, I come home, its dark and damn hard to see where problem is. Went for short drive this morning (3 Mi.) and definitely was burning off coolant, which I topped off last night. Parked under streetlamp near work, popped hood and a little mist coming from engine compartment. Nothing on top though, upper hose good, but thought I saw moisture on lower hoses. Question, if I have pressure test done to check system could it do more harm then good? I didn't even think to check tailpipe, but I checked oil level in dark, not over full, but could not tell color. Should I bring it to a shop? How will I know they ain't jerkin me around if they tell me its something serious and its only a hose?

Thanks,

Scruffboy

one time many years ago i took my supra to a toyota dealership and they insisted my head gasket was fine and they replaced the radiator .
they were wrong the car did have a seeping h gasket leak .

a compression check will give you some good data and it's cheap to get a gauge and do it yourself maybe 40 bucks for a gauge

sometimes the oil just doesn't show any signs of trouble

mine has a turbo and i've found that it's very easy to pull the oxygen sensor and check it for signs of a BHG .. it's just after the turbo elbow you want grey or black anything but white .

how about in the morning when you first start it up .. give it a little rev and see if you hear the water rushing sound from the middle of the dash

Re: Leak
 

I just replaced O2 sensor, do you think it would give me any indications seeing as it is so new? Also, If they perform compression test on coolant system, could that pressure blow the HG? That's what I'm worried about, them pumping up the system and creating more leaks. I made an appointment for this afternoon with a shop my friend used to work at. I plan to hang around and check what they do. Could valve cover gaskets go without blowing HG? I noticed the valve cover gasket looks a little ratty.

James

The coolant pressure test will show you where you have coolant leaks, it won't create new ones, unless they where just about to leak. The valve cover has nothing to do with cooling. If it looks bad replace it, that way it doesn't leak oil.

they pump up the pressure to just above were the pressure would be when your car was runing normaly so it wont create any leaks unless they did it when the engine was super cold.