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robdelorenzo · 09-02-2017, 10:18 PM

This just in.....

I changed the oil and filter and the car does run well.

But (there's always a catch here) I think the mechanic is right in that there is a circulation problem. I jacked the rear of the car and got under it while it's running.
There is a steady stream of drips of coolant constantly coming out. When the car is moving they vaporize so quickly that I don't see them. When I get the car hot enough or when the heat soak occurs, it really starts dumping coolant.

From what I can gather it seems like it's more than just an air bubble. Tonight after the oil change when I took it out for a very brief drive (I am getting wiser here) the temp gauge almost immediately went up to 180 before I even got out of the driveway. (It's never done that before it used to take a while to get up to temp)

So now my questions are centered around why there is a constant dumping of fluid.
The mechanic told me that the cap is designed to vent at 15 psi or thereabouts. So what is causing this to happen?

So far my hypotheses as to why this is happening after the meltdown are:

1. The impeller blades melted or broke off and are clogging the radiator, the thermostat or worst of all a coolant channel in the engine.

2. The thermostat was destroyed in the melt down and is permanently closed and not allowing coolant to circulate.

3. The water pump is bad and/or the impeller does not create enough coolant flow.

4. The radiator(s) are damaged or clogged from the melt down.

5. The bleeder valve is permanently open and is allowing air into the system. Should the little part that rises when you lift the wire go back down to being flush with the top of the valve when it's closed? The rubber in it is of really poor quality and the wire keeps coming out of the holes and is ripping the side of the piece that it lifts up and down. If this were the case, would the coolant or steam be coming out from under the valve where I wouldn't see anything?

6. It's still possible that there's air in the system, but would it constantly be leaking coolant (which it is as I have now confirmed) if this were the case or would it just dump occasionally as I had thought it was doing?

7. A pressure test was suggested, but I know that the coolant overflow hose is where the leak is coming from. If it's the thermostat or internal problems in the engine that's not going to help diagnose anything, is it?

8. The coolant tank has gone bad. I kind of doubt this one, as it's even dumping coolant on start up from stone cold and it's bone dry in the trunk. The ONLY place where it leaks is the overflow hose.

9. I can't think of anything else!

The strange thing is that tonight, as soon as I started the engine, there were drips of coolant coming out of the tube. From a stone cold start and it only started to flow more as the engine heated up. I had not noticed that happen before in the last few days since the mechanic fixed the pulley and belt.

This is very frustrating, but also kind of a fun (albeit expensive) challenge and a good learning experience. I plan on owning a Boxster of some sort until they pry it out of my old feeble hands many years down the road. So this knowledge is invaluable.

The question is where is the most logical and cheapest place to start given these symptoms? The temp gauge does not go into the red or even above 190 which is higher than it used to be prior to the meltdown. This is as it's spewing fluid out of the overflow.

I realize that I still may have an engine that's going to have a cracked head or cylinder looming in the future as a result of my idiotic decision to keep driving during the melt down last weekend. This line of thinking leads to me not putting too much more money into what's going on and walking away after inspecting the water pump and replacing the thermostat and/or the bleeder valve if they are indeed bad.

But, I also have faith that once I can figure out why it's leaking coolant I may have a chance to have many more miles of "Happy Boxstering" ahead. The challenge is to get to that point without going broke first!

Please keep up the flow of good advice. I feel like we are zeroing in on where the culprit may be.

I love this car and want to keep it alive if at all possible.

Thank you!

09-02-2017, 10:18 PM	#72
robdelorenzo Registered User Join Date: Mar 2017 Location: Los Angeles Posts: 356	This just in..... I changed the oil and filter and the car does run well. But (there's always a catch here) I think the mechanic is right in that there is a circulation problem. I jacked the rear of the car and got under it while it's running. There is a steady stream of drips of coolant constantly coming out. When the car is moving they vaporize so quickly that I don't see them. When I get the car hot enough or when the heat soak occurs, it really starts dumping coolant. From what I can gather it seems like it's more than just an air bubble. Tonight after the oil change when I took it out for a very brief drive (I am getting wiser here) the temp gauge almost immediately went up to 180 before I even got out of the driveway. (It's never done that before it used to take a while to get up to temp) So now my questions are centered around why there is a constant dumping of fluid. The mechanic told me that the cap is designed to vent at 15 psi or thereabouts. So what is causing this to happen? So far my hypotheses as to why this is happening after the meltdown are: 1. The impeller blades melted or broke off and are clogging the radiator, the thermostat or worst of all a coolant channel in the engine. 2. The thermostat was destroyed in the melt down and is permanently closed and not allowing coolant to circulate. 3. The water pump is bad and/or the impeller does not create enough coolant flow. 4. The radiator(s) are damaged or clogged from the melt down. 5. The bleeder valve is permanently open and is allowing air into the system. Should the little part that rises when you lift the wire go back down to being flush with the top of the valve when it's closed? The rubber in it is of really poor quality and the wire keeps coming out of the holes and is ripping the side of the piece that it lifts up and down. If this were the case, would the coolant or steam be coming out from under the valve where I wouldn't see anything? 6. It's still possible that there's air in the system, but would it constantly be leaking coolant (which it is as I have now confirmed) if this were the case or would it just dump occasionally as I had thought it was doing? 7. A pressure test was suggested, but I know that the coolant overflow hose is where the leak is coming from. If it's the thermostat or internal problems in the engine that's not going to help diagnose anything, is it? 8. The coolant tank has gone bad. I kind of doubt this one, as it's even dumping coolant on start up from stone cold and it's bone dry in the trunk. The ONLY place where it leaks is the overflow hose. 9. I can't think of anything else! The strange thing is that tonight, as soon as I started the engine, there were drips of coolant coming out of the tube. From a stone cold start and it only started to flow more as the engine heated up. I had not noticed that happen before in the last few days since the mechanic fixed the pulley and belt. This is very frustrating, but also kind of a fun (albeit expensive) challenge and a good learning experience. I plan on owning a Boxster of some sort until they pry it out of my old feeble hands many years down the road. So this knowledge is invaluable. The question is where is the most logical and cheapest place to start given these symptoms? The temp gauge does not go into the red or even above 190 which is higher than it used to be prior to the meltdown. This is as it's spewing fluid out of the overflow. I realize that I still may have an engine that's going to have a cracked head or cylinder looming in the future as a result of my idiotic decision to keep driving during the melt down last weekend. This line of thinking leads to me not putting too much more money into what's going on and walking away after inspecting the water pump and replacing the thermostat and/or the bleeder valve if they are indeed bad. But, I also have faith that once I can figure out why it's leaking coolant I may have a chance to have many more miles of "Happy Boxstering" ahead. The challenge is to get to that point without going broke first! Please keep up the flow of good advice. I feel like we are zeroing in on where the culprit may be. I love this car and want to keep it alive if at all possible. Thank you! Last edited by robdelorenzo; 09-02-2017 at 10:43 PM.