Coolant System Problems

[fiery_cayenne]

I have a 95 SC 400, had her for 3 years and had timing belt, water pump and 90,000 mile checkup and replacements done. She now has 134,000 miles and a problem. She's leaking coolant somewhere. When I start the car everything is fine, about the time the temp gauge reaches midway the heat comes on if there is enough antifreeze in the system. That's when white smoke starts coming out from under the hood. The car never overheats or even gets past the midpoint in the temp gauge. I have replaced the upper and lower radiator hoses hoping that it was a dry rot problem.......it wasn't. I took it to a mechanic that usually works on her and was told it was the radiator and $500 to fix it. After reading some posts here I'm not quite convinced. The mechanic has in the past charged me $50 for a $2 piece of plastic. Feel like I need a second opinion, any help?

[DaveMcKenz]

I have a 95 SC 400, had her for 3 years and had timing belt, water pump and 90,000 mile checkup and replacements done. She now has 134,000 miles and a problem. She's leaking coolant somewhere. When I start the car everything is fine, about the time the temp gauge reaches midway the heat comes on if there is enough antifreeze in the system. That's when white smoke starts coming out from under the hood. The car never overheats or even gets past the midpoint in the temp gauge. I have replaced the upper and lower radiator hoses hoping that it was a dry rot problem.......it wasn't. I took it to a mechanic that usually works on her and was told it was the radiator and $500 to fix it. After reading some posts here I'm not quite convinced. The mechanic has in the past charged me $50 for a $2 piece of plastic. Feel like I need a second opinion, any help?

I assume you can't see the leak. You might check the plastic coolant reservoir in the front of engine compartment. There is a level sensor which screws into it and sometimes cases a crack in the reservoir. Put a little soapy water on it and look for bubbles.

Just an idea.

[Tomj8]

I have a 95 SC 400, had her for 3 years and had timing belt, water pump and 90,000 mile checkup and replacements done. She now has 134,000 miles and a problem. She's leaking coolant somewhere. When I start the car everything is fine, about the time the temp gauge reaches midway the heat comes on if there is enough antifreeze in the system. That's when white smoke starts coming out from under the hood. The car never overheats or even gets past the midpoint in the temp gauge. I have replaced the upper and lower radiator hoses hoping that it was a dry rot problem.......it wasn't. I took it to a mechanic that usually works on her and was told it was the radiator and $500 to fix it. After reading some posts here I'm not quite convinced. The mechanic has in the past charged me $50 for a $2 piece of plastic. Feel like I need a second opinion, any help?

I assume you can't see the leak. You might check the plastic coolant reservoir in the front of engine compartment. There is a level sensor which screws into it and sometimes cases a crack in the reservoir. Put a little soapy water on it and look for bubbles.

Just an idea.

Ditto, I assume you see coolant on the ground but can't pinpoint the source...if so, consider checking the radiator cap. As the engine warms up and pressure builds a bad cap seal or a weak cap spring can allow coolant to get past and out the radiator overflow tube. And I'm thinking the "smoke" you refer to is actually steam since the engine isn't running hot. It is possible for a headgasket to blow through the waterjacket and to the outside of the engine - a situation that can cause coolant in the waterjacket to be blown out onto the exhaust manifold causing steam. Need to find the actual point source for the steam.

[fiery_cayenne]

I assume you can't see the leak. You might check the plastic coolant reservoir in the front of engine compartment. There is a level sensor which screws into it and sometimes cases a crack in the reservoir. Put a little soapy water on it and look for bubbles.

Just an idea.

I'll have to try that. The mechanic said it was definitely the radiator based on where it was wet. Personally I couldn't feel anything.

Ditto, I assume you see coolant on the ground but can't pinpoint the source...if so, consider checking the radiator cap. As the engine warms up and pressure builds a bad cap seal or a weak cap spring can allow coolant to get past and out the radiator overflow tube. And I'm thinking the "smoke" you refer to is actually steam since the engine isn't running hot. It is possible for a headgasket to blow through the waterjacket and to the outside of the engine - a situation that can cause coolant in the waterjacket to be blown out onto the exhaust manifold causing steam. Need to find the actual point source for the steam.

I believe it to be smoke due to the fact that when it started doing smoking it was fairly warm 50's outside and I had never seen it before at that temp from under the hood and seems to disapate more like smoke. Forgive my ignorance here, do you mean the reservoir cap or the bolt where the upper radiator hose connects?

[UCF3]

Wait, how much coolant is leaking? take a look at your main hoses from the radiator to the engine. if you feel moisture then troubleshoot from the radiator back.

[krazykorean35]

first, dont ever take your car to that mechanic again, hes a scam artist

try retracing all of the lines related to the cooling system. one of the hoses might have slipped off a little bit, just enough to leak.

[eatingupblacktop]

Doesn't take much to create steam. A small pin sized hole in a hose squirting coolant onto a hot engine or exhaust manifold can look like a major leak. In addition to the good advice already given, check the ends of your hoses at the clamps. Hoses tend to crack in that area, and coolant can sneak by the clamp. Also check your rad for bent fins from road debris or traces of coolant. Water pump could be leaking as well. Head gasket is unlikely unless you've had some serious overheating issues.

[PatrickB]

I have a 95 SC 400, had her for 3 years and had timing belt, water pump and 90,000 mile checkup and replacements done. She now has 134,000 miles and a problem. She's leaking coolant somewhere. When I start the car everything is fine, about the time the temp gauge reaches midway the heat comes on if there is enough antifreeze in the system. That's when white smoke starts coming out from under the hood. The car never overheats or even gets past the midpoint in the temp gauge. I have replaced the upper and lower radiator hoses hoping that it was a dry rot problem.......it wasn't. I took it to a mechanic that usually works on her and was told it was the radiator and $500 to fix it. After reading some posts here I'm not quite convinced. The mechanic has in the past charged me $50 for a $2 piece of plastic. Feel like I need a second opinion, any help?

I assume you can't see the leak. You might check the plastic coolant reservoir in the front of engine compartment. There is a level sensor which screws into it and sometimes cases a crack in the reservoir. Put a little soapy water on it and look for bubbles.

Just an idea.

My exact problem! Where does one buy a new plastic coolant reservoir, as I can't seem to find this part online? Is the rip off dealer parts department the only place to get one? :(

[DaveMcKenz]

I have a 95 SC 400, had her for 3 years and had timing belt, water pump and 90,000 mile checkup and replacements done. She now has 134,000 miles and a problem. She's leaking coolant somewhere. When I start the car everything is fine, about the time the temp gauge reaches midway the heat comes on if there is enough antifreeze in the system. That's when white smoke starts coming out from under the hood. The car never overheats or even gets past the midpoint in the temp gauge. I have replaced the upper and lower radiator hoses hoping that it was a dry rot problem.......it wasn't. I took it to a mechanic that usually works on her and was told it was the radiator and $500 to fix it. After reading some posts here I'm not quite convinced. The mechanic has in the past charged me $50 for a $2 piece of plastic. Feel like I need a second opinion, any help?

I assume you can't see the leak. You might check the plastic coolant reservoir in the front of engine compartment. There is a level sensor which screws into it and sometimes cases a crack in the reservoir. Put a little soapy water on it and look for bubbles.

Just an idea.

My exact problem! Where does one buy a new plastic coolant reservoir, as I can't seem to find this part online? Is the rip off dealer parts department the only place to get one? :(

I got mine from a member. Search "Aliga". He has supplied me with several very nice used parts. Also search "K & J Distributors". No personal experience but have heard they are good.