Help: Steam from RHS Vent/wheel well - 986 Forum - The Community for Porsche Boxster & Cayman Owners

dsisco · 12-01-2010, 01:46 PM

hey guys,

Was driving my car today, and had noticed i had steam coming out from the rhs vent or wheel well?

the car did was not over heating or anything,

does anyone know what could cause this?

Note: it was raining also

thanks in advance

Steve Tinker · 12-01-2010, 01:55 PM

Check your coolant level after the engine has cooled off completely.
You may have a split / leaking coolant tank. Lift the carpet and check if its wet in the rear boot (err, trunk in US parlance). If its still dry there, you may have blown some coolant out of the coolant tank overflow - it vents out just in front of the rear wheel on the right hand side (drivers side in Australia).
Use the search function for the reasons why it overflows.....

JFP in PA · 12-01-2010, 02:22 PM

As the right hand side vent is for engine compartment air (out), has a temperature controlled fan in it, and it was raining, I would not be worrying about it unless the car is losing coolant.......

dsisco · 12-02-2010, 12:15 AM

just checked the coolant and it was low, looks like it leaking more towards the center of under the car,

topped it up and drove home, didnt overheat or anything, but coolant still leaking,

checked the boot, not wet, leaks must be coming from the engine side

extanker · 12-02-2010, 02:58 AM

check the water pump

harryrcb · 12-02-2010, 05:50 AM

The tanks are prone to crack check everything thoroughly and don't drive it before you fix it. Also I don't know what year yours is but the tank cap has been updated due to this reason make sure you have an 04 cap.

dsisco · 12-02-2010, 05:10 PM

Water Pump has gone bye bye!!

lucky i ordered one the other day! as i was gonna replace it anyway

Jake Raby · 12-03-2010, 04:11 AM

Inspect the old pump for missing impeller blade pieces.. If it has any you MUST flush the entire cooling system until they are found, else a cracked head is in your future.

The engine could have overheated, it had to be hot for steam to be emitted from the overflow..

The coolant temp sensor is located centrally on the engine, if the pump takes a crap and the coolant isn't being circulated due to that, the sensor will never sample the hot coolant. Meanwhile the coolant in the heads is boiling hot!

Just because the gauge didn't show you a temp elevation doesn't mean the temperatures in the heads and cylinder didn't elevate. I'd go ahead and do a leakdown and compression test to ensure the cylinders didn't lose their integrity, just to be safe.

clickman · 12-03-2010, 07:49 AM

Quote:

Originally Posted by Jake Raby

The coolant temp sensor is located centrally on the engine, if the pump takes a crap and the coolant isn't being circulated due to that, the sensor will never sample the hot coolant.

Great.

So much for an important reason for the temperature gauge.

Jake Raby · 12-03-2010, 09:07 AM

There is no substitute for paying attention to the engine...

If the sender isn't getting hotter coolant moved across it, because the pump has completely failed, it can't take an accurate temp reading.

extanker · 12-03-2010, 09:20 AM

its the lack of coolant that causes cracks etc not the temp of the coolant. for better than 50 years most coolant sensors stop working when they dont have coolant around....they are after all coolant temp sensors not metal temp sensors,a coolant level sensor is a big leap foward

dsisco · 12-03-2010, 01:33 PM

Quote:

Originally Posted by Jake Raby

Inspect the old pump for missing impeller blade pieces.. If it has any you MUST flush the entire cooling system until they are found, else a cracked head is in your future.

The engine could have overheated, it had to be hot for steam to be emitted from the overflow..

The coolant temp sensor is located centrally on the engine, if the pump takes a crap and the coolant isn't being circulated due to that, the sensor will never sample the hot coolant. Meanwhile the coolant in the heads is boiling hot!

Just because the gauge didn't show you a temp elevation doesn't mean the temperatures in the heads and cylinder didn't elevate. I'd go ahead and do a leakdown and compression test to ensure the cylinders didn't lose their integrity, just to be safe.

thanks Jake i rate your input very highly,
once i remove everything i will take a look, was gonna fluch the whole coolant system anyway, as we have just got into summer here in australia,

i think i actually jinxed my self, i actually ordered waterpump kit with low temp thermo, 3 days before this happened,

extanker · 12-03-2010, 02:06 PM

it has to be reverse flushed

dsisco · 12-04-2010, 06:29 PM

Quote:

Originally Posted by extanker

it has to be reverse flushed

how do you reverse flush?

extanker · 12-05-2010, 05:57 AM

what ever hose the waterpump uses for out put you want to run water [flush] inward. any blockage cant go foward so you reverse it

Steve Tinker · 12-05-2010, 03:10 PM

And wouldn't you have to remove the thermostat from its housing to get flow - when I reversed flushed my MV Agusta cooling system I got no flow untill the 'stat was removed......

extanker · 12-05-2010, 03:26 PM

Quote:

Originally Posted by Steve Tinker

And wouldn't you have to remove the thermostat from its housing to get flow - when I reversed flushed my MV Agusta cooling system I got no flow untill the 'stat was removed......

i dont know but you sound right.....mine is a new car and i aint keeping it long enuf for the pump to go bad