johnsc400

Ok ive been having some odd coolant problems. Usually I check the coolant levels on my driveway and when I check about 3weeks ago it was low so I filled it up and then a few days later it was low again. Then I realized I was parked on an upward slope so when I got the car level the coolant was normal. About every 4days I need to add about a 1/2quart of coolant. Im sure there is a leak I just cant locate it. Today im driving on the freeway and my low coolant warning pops up. My temp gauge is right where its supposed to be. Sometimes it is even lower than its supposed to be. Im thinking maybe the guy who sold me the car knew about the leak and maybe switched to a colder thermostat but I dont know. So anyway I pop the hood and the resovior is fine. Its not completely full but its more than halfway. I dont understand why the light popped on now and it never did before when there was hardly any coolant in the resovior.

Lexgendboi

iTrader: (1)

yah...recently i just got the same problem. I checked and filled the coolant 3-4 times already, but the coolant warning light kept pop up sometime(most of the time when it's hot out). The temp gauge is at the right operating temp. I was thinking about checking and changing the thermostat and also the coolant cap(probably to 1.0 bar instead of 0.9 OEM). I'll post up message once i got my hand on it.

pcmw

Does the engine bay smell like coolant after you shut the car down?

Maybe the radiator cap is failing to hold the pre-set pressure it was designed for. If this is the case, then the cap is bad and you need a $5 part. What is happening is that the car is heating up, the coolant is actually becoming gas (steam), thus leaking out thru the TOP and then when cooling down...may appear to be at the same level.

I would do a complete coolant flush, change the thermostat and radiator cap.

MW

Neal Rikal

The problem you are having is most likely hairline cracks in the plastic tank in your radiator. these cracks allow coolant to slowly leak out. i just replaced mine myself last week. my problem started out just like yours, but it only gets worse. you can get a radiator shipped for 5$ overnight for 146 dollars total i believe. the nice parts are that it is all steel (not plastic) with a lifetime warranty that bolts up just like the stock one. You use the same bolts and hoses. I have had no problems what so ever with mine and all you need to do is jack your car up and get under there, its pretty basic stuff. you can find the radiators at: http://www.auto-car-radiators.com

VQT

Definitely there is a leak in the system if you have to refill the resevoir every 3/4 days. I drove my 93 SC400 with 130K+ miles from Philadelphia to LA the long way (more than 4500 miles) and no drop in the resevoir.

What year is your SC400? How many miles? When was the last time you flush the radiator?
Do you have different size tires on the car? stiffer suppension?

Radiator with plastic cover will crack after many miles of usage and the vibration it subject to. You need to check the radiator carefully to see where the leaks at. It could also be your hoses have small hole in it. Look for abnormal color around the engine bay (the water that spill out from the radiator; either from the hoses or the radiator will leave evident). If it is the radiator, you need to pull it out and have it pressure test and fix or buy new radiator to replace.

Good Luck and keep us up dated
VQT

SharpLS-96

Have your radiator pressure tested or just have them put a dye material in to see where the leak is occuring. Then come back a few days later and they will check with a blue light for the leak.

Good Luck

johnsc400

Thanks for the input. Its a 92sc400 with 125k. I think the leak may be coming from the resovior itself. Im just going to get it checked when I get some time. I don't really mind adding water every 3days but I dont want to have a major spill one day and be stranded. thanks again