240sx "REALLY STRANGE COOLANT PROBLEM"

[(Q)240]

Car: 1992 240sx Ka24de

PROBLEM:My car is losing coolant and alot of if is going nowhere.what i did was fill my radiator to the top and my resorvior tank half way. (Just as it should be). I drove somewhere and when i got back home i check my radiator and find out its no longer filled to the top. but then i see my resorvior tank and notice its above the max it should have. Im guesing the coolant went from my radiator to the resorvior tank. but its leaving my radiator empty and overloading my resorvior tank & might make my car heat up since the radiator is empty.

anyone know what this could be? let me know please

Thanks!
Modified by (Q)240 at 4:52 PM 8/29/2008

[Lost_In_Translation]

There is no way that all the water from the radiator could fit in the reservoir but it seems your car is overheating and pushing water out to the reservoir... did the car had any overheating problems recently? or have you flushed the radiator or something?

[480sx]

Check your radiator cap, might be bad. Easiest thing to swap out to try for an easy fix.

If your car isnt overheating theres a good possibility its just your cap.

[redtop240]

Um...Tell me if I am wrong, dose'nt the coolant expand and rise from the heat? Creating the level to fluxuate in the resivor tank. That is why there is a maxium and minium line!

[(Q)240]

There is no way that all the water from the radiator could fit in the reservoir but it seems your car is overheating and pushing water out to the reservoir... did the car had any overheating problems recently? or have you flushed the radiator or something?

not all but most of it.. had no over heating problems.. and yes i did a radiator flush id say about 2 months agohow can i check if the cap is bad? just change it?
Modified by (Q)240 at 2:47 PM 8/16/2008

[carkook]

Um...Tell me if I am wrong, dose'nt the coolant expand and rise from the heat? Creating the level to fluxuate in the resivor tank. That is why there is a maxium and minium line!

Nice pointless post buddy, but anyway, yes the resevior tank amount should fluctaute but not enough to drain your radiator and make your car run hot. Its probably your cap which was said already. Its not holding to enough pressure and its letting coolant out instead of being pushed through your motor.

[Sentientbydesign]

You guys are all so nice to each other

Sounds like a pressure problem (already stated, I know). If it's not the cap, which you should replace for the hell of it, it might be that the resevoir isn't holding pressure either (some resevoirs do, others don't). Not sure which the 240 has.

[(Q)240]

i changed my radioator cap today... havent droven it yet. but ill check asap.

Thanks!

[DINO THE WHEEL GUY]

did you bleed the system ?its up near the temp sensor plug

[(Q)240]

did you bleed the system ?its up near the temp sensor plug

nope i havent. where exactly is that?

[DINO THE WHEEL GUY]

look at the autozone web site and look up coolant bleeding for your car and it will give you pics and how to go about it.and it will only take you about ten minutes to do

[(Q)240]

so its been a week without looking at the coolant.. and today i was driving somewhere and when i almost got to the place the temp needle went up passed the middle... so i turned the car off then turned it back on. and it was still kinda marking alot hotter than usual... so i get the place and let it cool down.. get back like 30 mins later.. open the Radiator and it was empty. the resorvior tank had enough coolant. so i refilled the radiator up to the top. and turned the car on and drove fine.. no overheating... SO.. i know now that its the coolant disappearing. I dont think i saw any leaks so i guess its getting burnned. SO WHAT COULD THIS BE?i doubt the HG is bad. cause my oil is fine and its not smoking white or anything.ANYBODY?

[Sentientbydesign]

Do you smell the radiator coolant?

It is sweet like maple syrup.

I'd wash the engine out when it's cool and that should help you determine where the coolant is leaking (if it is).

You can also just leave the car on with the a/c running (assuming it works) and that should heat up your car enough to see where the coolant is going.

Did you replace the cap like we told you?

[(Q)240]

i smell hot coolant around my radiator... nothing sweet though... and yea i changed the cap and still nothing.. but im check today if i see any leaks

[Sentientbydesign]

You might be using a coolant only and it doesn't have the alcohol portion used for anti-freeze. I think the alcohol is what smells sweet.

You can also buy a UV tracer to add to the coolant to help find the leak.

[(Q)240]

but what are things that could cause a leak besides a hose?

[emo_tactical9]

Well, it's either leaking or getting burned in the cylinder. Does it have steam coming out of the exhaust? No?Then it has to be leaking somewhere. Are you running the heater when filling it up?

[(Q)240]

Well, it's either leaking or getting burned in the cylinder. Does it have steam coming out of the exhaust? No?Then it has to be leaking somewhere. Are you running the heater when filling it up?

no smoke or steam coming from the exhaust. and no leaks anywhere at all.. and what do you mean by RUNNING the heater while filling it up? its not overheating with coolant in it... its just loosing coolant and thats what makes it overheat. but cant find where the coolant is going. BTW IT TAKES ABOUT 5 DAYS AFTER I FILL UP THE RADIATOR FOR THE RADIATOR TO GET BACK TO EMPTY AND CAUSE THE CAR TO OVERHEAT.

[Sentientbydesign]

This is what concerns me.

The radiator and resevoir are supposed to work in unison. If the radiator gets too hot, it spill some coolant into the resevoir, if it "burns" off some coolant or it's colder, it pulls from the resevoir.

If the radiator just dumps coolant into the....I just thought of something.

Does the resevoir overflow excess coolant? Maybe there is a flow restriction in your radiator that is causing pressure and pushing coolant into the resevoir. The resevoir gets to it's max capacity, then starts dumping coolant.

That stuff doesn't just magically dissappear. It's either being burned (HG), leaking, evaporating (really not likely), or escaping somewhere else (resevoir).

[(Q)240]

your right yes the resevior has more coolant than i remember putting but if it was dumping the coolant wouldnt that be noticable? I just finished checking for any leaks. had the car on for about 10 minutes drove it for like 3 minutes.. then left it on for 10 minutes more and found no leaks or drips what so ever. No white smoke coming from the exhaust & my oil looks fine.

[psmith]

not all but most of it.. had no over heating problems.. and yes i did a radiator flush id say about 2 months agohow can i check if the cap is bad? just change it?

Modified by (Q)240 at 2:47 PM 8/16/2008

Did you have any problems like this before you did the flush?

[low91240sx]

Sounds like a problem that I had with my first 240 and it turned out to be the Head Gasket try running your car until it gets hot and the when you shut it off see if you can hear the coolant bubbling in the resevor that's what mine did and I could see oil coming from the right side of the engine so do that and check to see if you can see any oil I know you said that it seems fine but it doesn't hurt to check

[(Q)240]

Did you have any problems like this before you did the flush?

nope only time it overheated before was cause it was leaking coolant through the water pump but i replaced the water pump with a new one and everything was fine...that was id say about 4 months ago this is the only time i see my coolant going no where...

[(Q)240]

Sounds like a problem that I had with my first 240 and it turned out to be the Head Gasket try running your car until it gets hot and the when you shut it off see if you can hear the coolant bubbling in the resevor that's what mine did and I could see oil coming from the right side of the engine so do that and check to see if you can see any oil I know you said that it seems fine but it doesn't hurt to check

nothing.. ive left it on to warm up.. no white smoke.. no milky oil. everythings the same except its losing coolant

[cleopp3]

did u replace all the components? when u do a flush especially with flush fluid it eats away all grime sometimes exposing a pinsized hole or what ever. check that water pump, as well as the themostat. you may just have an extreme air bubble locked in there. coolants getting sucked up into the bubbles.how much exactly are u losing? like a whole jug or can u still see the fluid from the top?

[(Q)240]

im sure the water pump is ok... but it takes id say about 5 days after i fill it up to get back to empty and make it overheat..

[(Q)240]

anybody have any other ideas of whats causing this?

[TuRbOS13]

I've had the same problem. Mine was because my overflow tank wasn't the right one for my car. When my car would get hot and the coolant ran into the overflow and since my tank was not made for my car it sat low in the engine bay and should have been higher so that the coolant would flow back into the radiator by the hoses. Since it sat too low it would just stay in the overflow. Just check ur overflow tank and make sure the hoses going to ur radiator are going from a higher angle than ur radiator sets.

[Ignacius_Rebenga]

Maybe you need a new RADIATOR!!!! and rad to motor hoses and rad to resorvoir hose

[Cone Junky]

PRESSURE TEST, PRESSURE TEST, PRESSURE TEST!

Did I mention you should do a pressure test? It will reveal any external leaks or you can leave it pressurized and pull the spark plugs. If you keep it under pressure and let it cool down all the way, the cylinders will get coolant in them if you have a head gasket leak.