My radiator leaks saga continues
02-14-2014, 11:44 PM
#16
Chronic Tool Dropper
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Hi again,
Well I got the car up on ramps and pulled the fan shrouds and belly pan. I pumped the cooling system tester up gradually. When I got to 9-10 psi I began to detect wetness at the PS tank seal at the bottom. I cannot see any particular place on the seam where it is originating. The drain plug, trans cooler, and hoses are completely dry. At 10 psi I get about one drop of coolant every 5-10 minutes.
The radiator has a one year warranty, so I plan to contact 928 Int'l with pictures to see what they are willing to do. Any further suggestions? BTW my OEM coolant cap says "100" on it which I assume is one bar or 14.5 psi. I am tempted to order Carl's 7 psi coolant cap, and see what that does.
Thanks for all,
Dave
Well I got the car up on ramps and pulled the fan shrouds and belly pan. I pumped the cooling system tester up gradually. When I got to 9-10 psi I began to detect wetness at the PS tank seal at the bottom. I cannot see any particular place on the seam where it is originating. The drain plug, trans cooler, and hoses are completely dry. At 10 psi I get about one drop of coolant every 5-10 minutes.
The radiator has a one year warranty, so I plan to contact 928 Int'l with pictures to see what they are willing to do. Any further suggestions? BTW my OEM coolant cap says "100" on it which I assume is one bar or 14.5 psi. I am tempted to order Carl's 7 psi coolant cap, and see what that does.
Thanks for all,
Dave
On the lower-pressure cap: The system really does need to be able to hold more pressure to keep the coolant liquid. Consider that there are hotter and cooler areas in the engine. Heads and tops of cylinders pass more heat than the bottoms of those same cylinders. Passages in the head on the exhaust side pass more heat then the intake side. When low-pressure coolant hits the hot spots, it may boil to vapor just in that area. The local heat is shared with the rest of the coolant as it circulates, so you may not notice the effect. Nonetless, the boiling means less heat is carried away since the bubbles prevent liquid contact with the hot surface. The creation and collapse of the bubbles cause mechanical erosion damage, like little bombs going off in the coolant as it flows. The lower-pressure cap masks weaknesses in the rest of the system, but in my limited experience it's just a band-aid to let you get home and fix the problem. Another thought is that the factory built the car to survive all kinds of thermal abuse hot and cold weather, all with relatively new engines without the protective scale in the water jackets. With a 1bar cap.
02-15-2014, 12:00 AM
#17
Rennlist Member
If you are still having trouble finding the leak, try uv dye in the coolant and then use the uv light to find the leak. I have used this on many cars and it is foolproof. Many brands available, just make sure you get a quality unit.
02-15-2014, 12:14 AM
#18
Rennlist Member
Thread Starter
Thanks Bob,
I kind of think that since I have ruled out installation related leaks from drain plug, hoses or trans cooler, a radiator leak will be a warranty claim. I am getting pretty good at r & r'ing the rad, but even if I narrow down the leak to a particular point on the seam, the rad still goes back to the vendor. I think I have taken it as far as I want to go right now. I have sent pictures to Tom and will wait to see what he wants to do. The reason I bought a used radiator was my original had a PS tank seal leak,(repair attempted unsuccessfully), and this radiator has the same, but to a lesser degree.
Thanks,
Dave
I kind of think that since I have ruled out installation related leaks from drain plug, hoses or trans cooler, a radiator leak will be a warranty claim. I am getting pretty good at r & r'ing the rad, but even if I narrow down the leak to a particular point on the seam, the rad still goes back to the vendor. I think I have taken it as far as I want to go right now. I have sent pictures to Tom and will wait to see what he wants to do. The reason I bought a used radiator was my original had a PS tank seal leak,(repair attempted unsuccessfully), and this radiator has the same, but to a lesser degree.
Thanks,
Dave