Coolant Temp Hitting and Sitting at 225f

[Ahsai]

Congrats. Glad you found the culprit.

[bigmsm]

 

OK - Found the "leak"! - Only its not a leak.  Its not coolant, its pure water coming from A/C out a drain duct between two black plastic pipes about under the passenger seat - duh! Used the new Stant 12270 and pressure sat at 19 psi for 3 minutes or so (dropped a teeny bit over 3 minutes --> one quarter of the width of the 9 font in 19 psi label.)  Does that count as holding sufficient pressure? I got the VW adapter for the Stant, but I think I need something else to test the cap, but if I just replaced it with new OEM part 4 months ago I am doubting that is worth testing? Does that sound right or should I still get the part and test the new cap? I have pretty much dismissed lack of pressure as my issue. Reputable dealer did the coolant flush so I assume got the air out, but now kind of wish I got a vacuum tool.  So next I went to rule out dirty radiators as the issue.  I had already vacuumed the a/c condensers and the edges of the radiator through the bumper ducts and they looked good, but based on advice from this forum I removed the bumper to get behind the A?C condensers and HOLY MOSES there was a lot of dirt, former shrubbery, seeds and sand.  Bought a air compressor from Harbor Freight to blow crap from back to front. Then decided I needed to blast from behind the radiator (covered condenser) and removed the radiator brackets and fans, and removed a small beach of sand from the radiators ( I drive along the coast everyday). It might be a little better but coming to work today I was at 100c-103c the last 30 min of the drive and it was only 70 f ambient so I don't think I have solved my problem.  Low fans are late to kick in at over 100 without AC on. High fans kick in at 102-4c and they do drop the temp back to 100c-102c.    So next step sounds like going after the water pump and thermostat?  Do you agree this is worth chasing down? I am afraid that if I can hit 107c in 80f ambient, then 90f with AC has gotta get me to even higher levels. Many thanks for the input.  

 

Normally, we let pressure tests sit for at least 15 to 30 min. to see if they hold pressure.  From your test description, you are probably fine.

 

Not surprised you found enough stuff in the radiators for your own National Geographic special; that is a common thing with these cars.

 

I don't remember how many miles are on the car, but the water pumps in these vehicles should be considered a maintenance item that needs to be periodically replaced.

 

 

I'm installing my 3rd pump and 2nd tank in a bit over 4 years. How often should "periodic" be?

[JFP in PA]

Water pumps are maintence items at around 40K miles unless they start to leak or make noise earlier.   Surge tanks are less mileage dependent, some actually going the life of the car.  By far, the biggest reason we see for early failures of either, and in particular the tanks, is the use of aftermarket parts.  We have seen third party water pumps not make it 3K miles, and aftermarket tanks so poorly made that they would fail right out of the box, which is why we only use the factory units.

[bigmsm]

Thanks JFP.  Had pump, thermo and tank replaced (all OEM) and car is running hotter than normal.  Averaging gauge, probably around 210 when it used to run 190-195.  Mechanic said to monitor it but "they have noticed new water pumps and thermostats running a bit hotter".

 

Anyone else notice that?

[JFP in PA]

Thanks JFP.  Had pump, thermo and tank replaced (all OEM) and car is running hotter than normal.  Averaging gauge, probably around 210 when it used to run 190-195.  Mechanic said to monitor it but "they have noticed new water pumps and thermostats running a bit hotter".

 

Anyone else notice that?

 

Not really.  The new thermostat may be a bit hotter than the old one, unless you used the LN low temp unit.  I would also hook the car up to a Porsche diagnostic tool and check the coolant temp with that, the dash gauges in these cars are not known for their accuracy.