Zoomspeed

ok, I elminated my AST on friday, but since then I've been having a problem.

Now every time I let the car sit for more then a few hours. When I start it up I get the low coolant warning, then I have to add coolant. I have to put in enough to fill up the t-stat housing plus a little more. After I fill it up I can drive just liek normal to where ever w/o any problems.

I've had to fill it up it up in this manner every morning before I goto school, and every night before I leave work, ever since friday.

I've looked under the car after its been sitting a while, and I dont' see any coolant on the floor, I've poked around the engine bay at allt he stuff I messed with and I dont' see any leakin coolant, and by looking at my exahsut I'm not burning any.

I'm running evans NPG+ w/ a 0 PSI pressure cap if that means anything.

Wheres all my coolant going?

THanks for any help.

tfhuth

If it's not showing up on the ground, and it's not going out the exhaust, then you may want to check your oil level. Good luck, Tom

ronarndt

You may not be able to detect a small coolant leak into the combustion chamber by looking at the exhaust. When my coolant o-rings went bad, there was no exhaust smoke and the car ran fine- it just lost about a pint of coolant per hour when I drove it. You need to have a competent radiator repair shop do a pressure hold test to check for leaks AND a test to detect exhaust in the coolant. You can do both of these yourself, if you have the equipment, but for about $30-40, you can have it checked for you. Or- you may have an internal leak which allows the coolant to go somewhere else- like into the oil. Does the oil look milky or like pudding? Were you losing coolant before you did the AST removal? Hope you find some simple fix, otherwise if it is your coolant o-rings, you will need to go the engine replacement route, like many of us have done already. Ron A.

Zoomspeed

Iw an't loosing any before the AST elmination.

u guys are making me scared I was hoping its just air in the system working its way to the top.

How woudl I do the testing myself? I wrok at autozone so I ahve access to some equipment.

Zoomspeed

oh another thing, I can drive for a while, and the low coolant light wont come on or anything. Just yesterday I filled up the coolant some, and I drove about 40 miles with no problems. Then after work (about 5 hours later) I start it up and get the low coolant warning.

Zoomspeed

Now that I think of it, on monday, I filled it before I went to work. Work is only a 1 minute drive away from home. AFter I got out of work (about 6 hours later) I had to fill it again becasue the low coolant light went on again. If I was burning coolant then I wouldn't have gone through that much, otherwise I wouldn't ahve been able to make that 40 mile trip on tuesday. Am I making sense?

Mahjik

iTrader: (1)

Zoomspeed,

Is the coolant actually low when you fill it or are you just filling it because of the coolant buzzer?

When my coolant seals were gone, the coolant buzzer would only go off when the car first started and if the car sat and idled for a few minutes (like sitting in traffic, or in a drive-thru for fast food).

afterburner

Hope you just need to burp the coolant system.

RCCAZ 1

iTrader: (10)

I agree with you afterburner. I also purchased the AST elimination kit 2 years ago and had erratic coolant level readings (although my buzzer never went off) until someone at SevenStock 4 explained the proper filling and burping procedure for Gen 3s. There are a lot of guys driving around with air in their systems who are unaware of the proper filling technique. I also made a decision to remove my AST elimination kit and reinstalled a Tripoint aluminum AST. I figured that the car was designed with the AST for a reason, plus the extra quart of coolant that the aluminum AST provides is a plus in the Arizona heat!

ronarndt

Zoomspeed- Have you burped all the air out of the system? You may have to fill, let cool, fill, let cool, fill, let cool several cycles to get all the air out. Also- if there is even a slight pinhole or air leak in any of your coolant hoses or connections, you will suck air back into the system as the engine cools. A small pinhole may not allow any coolant to leak out under pressure, but as the engine cools and tries to suck the coolant back from the coolant overflow tank near the passenger fenderwell, it draws air into the system instead and leaves the "expanded" coolant in the overflow tank. Does the level in your overflow reservoir keep going up? Check all your hoses and connections, tighten all the hose clamps. If you work at Autozone, get decent hose clamps and replace those POS things that came from the factory. See if your store has the fluorescent dye and the blacklight that is used to check for leaks. If you use the dye, it will fluoresce and detect even small leaks when you shine the blacklight on it.
Ron A.

Zoomspeed

I did bleed the system some. probably not as thoroughly as I should have. I just carried an extra gallon of coolant in my car incase it got low, but now I've gone through most of that gallon.

I notcied today the coolant is being pushed out to the over flow somehow. Its actully overflowing out of the overflow.

tfhuth

Good call Ronardt. Now all you have to do is find out where you are losing vaccum ( as in the kind created in your cooling system as your motor cools ). Mine was a dent in the ast filler neck. I kept pushing coolant into the overflow, and it was not returning. Took me a week to find it. Obviously you should look at the last things you changed. Good luck, Tom

tox

Hey Zoom, did you ever check your oil? My coolant seals are bad and I am going to need a rebuild. My oil was milky looking. I hope that isn't the case for you.
I have been putting "block sealer" in the coolant system to help stop the leak. So far it has worked...when I changed my oil, there was no more coolant.

I have a 93' rex. My fans don't come on when the car is not running. I believe this was a factory recall and I would assume that the excess heat in the engine compartment probably caused my seals to go before their time...dunno.

Zoomspeed

I jsut did an oil cahnge, it all looked good.

Mahjik

iTrader: (1)

Zoomspeed,

It sounds like you just need to burp the coolant system. The coolant spilling out just sounds like you are overfilling (because you are adding coolant in when you don't really need to).

There was a thread a while ago about how to go about burping the system, which basically consisted of doing some hose squeezing and such. You might do a search and see if that technique will help you out.

Mahjik

iTrader: (1)

Here ya go, try this:

https://www.rx7club.com/forum/showth...hlight=squeeze

TYSON

Did you measure the coolant you took out VS the coolant you put in when you did the swap? It took me an entire weekend of checking every hour or so before my level stopped going down.

duboisr

garfinkle took my tank off and it took a long time to burp the system . After several days of putting in a cup at a time it quit .Now after a long time I have not added any water at all .The car cools fine .

series6bat

Im getting the very same probelm
But i have been driving my car and every mornin i will fill up a little more at a time.I also get a lot of rushing around in the overflow.I just need to keep burping the system.
I think u will to
The rushing is gettin less though