Diagnose my 987.2 coolant leak!
07-23-2024, 12:26 AM
#1
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Diagnose my 987.2 coolant leak!
The leak is on the extreme passenger side behind the wheel. Seems under the reservoir.
Just installed new water pump/thermostat. Used a vacuum fill. It held vacuum well enough to fully fill the system. I test drove it twice in town then parked for a week with the rear jacked up. Went to change oil, checked coolant and it was way down. Engine off I Poured in coolant and could hear drips and then see a puddle. So it seems unlikely to be the water pump.
The original leak that led me to replace the pump happened similarly. Leak while parked.
the old pump did have a bit of bearing play so I thought I’d solved it. Guess I wasted a lot of time, but at least now I know how to do that job.
So. The system holds a a vacuum with slight, slow loss. Is this likely the reservoir or a hose from the filler tube or reservoir to engine?
How does it work fine with no loss during operation and then drain down while parked?
very confused.
Just installed new water pump/thermostat. Used a vacuum fill. It held vacuum well enough to fully fill the system. I test drove it twice in town then parked for a week with the rear jacked up. Went to change oil, checked coolant and it was way down. Engine off I Poured in coolant and could hear drips and then see a puddle. So it seems unlikely to be the water pump.
The original leak that led me to replace the pump happened similarly. Leak while parked.
the old pump did have a bit of bearing play so I thought I’d solved it. Guess I wasted a lot of time, but at least now I know how to do that job.
So. The system holds a a vacuum with slight, slow loss. Is this likely the reservoir or a hose from the filler tube or reservoir to engine?
How does it work fine with no loss during operation and then drain down while parked?
very confused.
Yesterday, 12:03 AM
#2
Well, on the upside, at least it's easier to look for a leak when the car is parked 😬
The behavior is odd though. I had something similar where it would dump some coolant when parked also. I replaced the coolant tank and the pressure vent but I think the vent was actually the culprit. The tank is annoying and fiddly to remove and a lot more expensive than the pressure valve so I'd start with the cap/valve. I think my mistake was not using a proper lubricant on the o-rings during installation the first time I replaced it. The second time I used silicone and it went together much more smoothly and I didn't need the tighteningn of the bolts to fully seat it. I was able to twist it while pushing and seat it fully. Then I installed the bolts.
The behavior is odd though. I had something similar where it would dump some coolant when parked also. I replaced the coolant tank and the pressure vent but I think the vent was actually the culprit. The tank is annoying and fiddly to remove and a lot more expensive than the pressure valve so I'd start with the cap/valve. I think my mistake was not using a proper lubricant on the o-rings during installation the first time I replaced it. The second time I used silicone and it went together much more smoothly and I didn't need the tighteningn of the bolts to fully seat it. I was able to twist it while pushing and seat it fully. Then I installed the bolts.