Major Overheating Issues w/ P5. Time to Cut Ties?

[carter1551]

My car overheated on the freeway a few days ago. It went from operating normally on my work commute to huge plumes of smoke within a second. I pulled over as quickly as I could. My radiator had a major crack and it all gave way at once on my commute. Had mechanic replace it and the hoses and it's still overheats. I managed to get it home using the hot air vent trick.

I swapped the thermostat on my own and it still overheats but the radiator is somehow cool to the touch. After the thermo install I now get no hot air from the vents. The top hose gets hot and the bottom hose doesn't even feel warm. Lastly, the coolant does not seem to cycle at all. I dumped about half capacity in the radiator after the thermo install and filled up the reservoir. It NEVER pulled from the reservoir and the level never seemed to change in the radiator either. I checked the levels after the test drive and then let it idle in the driveway with the rad cap off for 5 minutes and neither affected the coolant level.

Three Possibilities in my Book:

1. I somehow messed up installing the Thermostat and it's stuck closed.
2. The water pump suffered damage from running low or dry when my radiator burst.
3. Head Gasket/Warped Head

HELP ME SORT THIS OUT WITH YOUR THOUGHTS PLEASE!

 

[MrGiggles]

Borrow a block tester from O'Reillys or Autozone. You'll need to buy the 10.00 fluid for it. If it fails this test and the fluid turns yellow, the head gasket is leaking.

There's not much to fail in a water pump, but in rare cases the impeller can rust away or fall off.

Have you tried running it without the thermostat to check for coolant flow?

 

[00protegees]

Could be an air bubble. Wonder if they didn't burp the system completely. Leave the cap off and let the car idle. When it comes up to temp, the water will circulate, letting all the air work its way out

 

[carter1551]

Borrow a block tester from O'Reillys or Autozone. You'll need to buy the 10.00 fluid for it. If it fails this test and the fluid turns yellow, the head gasket is leaking.

There's not much to fail in a water pump, but in rare cases the impeller can rust away or fall off.

Have you tried running it without the thermostat to check for coolant flow?

I was debating removing the thermo altogether. I'll try this tomorrow and see if it makes any immediate difference.

Did not realize I could rent a block tester so that'll be a good next step if the thermostat removal makes no difference.

 

[carter1551]

Could be an air bubble. Wonder if they didn't burp the system completely. Leave the cap off and let the car idle. When it comes up to temp, the water will circulate, letting all the air work its way out

I tried that for about 5 minutes. With cap off I idled at 1.5k for 2 minutes and then 2k for 2-3 minutes. Didn't alter the level of coolant. Maybe I need to do it longer?

 

[MrGiggles]

I was debating removing the thermo altogether. I'll try this tomorrow and see if it makes any immediate difference.

Did not realize I could rent a block tester so that'll be a good next step if the thermostat removal makes no difference.

You don't want to run without the thermostat for long. Coolant cannot absorb heat from the engine efficiently if it's constantly flowing. By removing the thermostat, you just mask the problem. The coolant never gets hot, but that's because it is not actually transferring any heat from the engine.

There is also the issue of oil sludge and never reaching closed loop operation. I only recommended thermostat removal to check for water pump function.

 

[00protegees]

Dont take offense to this question....but did you possibly install the thermostat upside down? That wouldnt really explain why it overheated from the mechanic but its still a possibility. I dont think these cars had problems with shredding water pump impellers, so I would only look at the water pump as a last resort.

As far as burping the system, 5 minutes may or may not have been long enough. The car should come up to operating temperature, where the thermostat would open. That'll start to circulate coolant, and you should feel the upper hose get warm. If your car overheats with the cap off, and the upper hose doesnt get warm, its either the thermostat or water pump.

Im assuming your radiator is completely topped off right? It should be absolutely full right to the top, then fill the overflow up a bit.

Also, pull the oil cap off and look for milky residue, that'll give indication of head gasket failure

 

[Maroon]

All signs point to a bad thermostat or an improperly installed one. I don't know if you can install the thermostat for this car backwards, but on other vehicles, you can't. It just won't fit.

 

[pcb]

I think she's just got a big bubble and needs a good belch...

As do I ..





On a semi-sober note... You can put the rad cap on while it's warming up and pump the upper rad hose... That can help to breakup an airlock...

Don't forget to turn everything to full heat to open the heater core... (especially if an airlock happens to be in the heater core)

 

[carter1551]

UPDATE: I went out yesterday to to some more investigating and I noticed that my coolant reservoir was now empty. So I filled it back up and it hasn't shown signs of overheating since. Wondering if since I parked on an incline that somehow an air bubble worked itself out overnight.