I have a recently purchased 1996 Honda ST1100 (standard) with only 45,000 miles.
After a long hard test ride tonight that included a mixture of high & low speed, I shut of the engine & inspected the bike with a flash light.
I then noticed a small stream of bubbles within the coolant in the overflow tank.
Also, the level of coolant in the reserve tank does not increase & decrease with thermal cycling of the engine like it should.
Also, there is a mysterious loss of coolant (only about 2 cups) over 3 days of riding. There are no visible coolant leaks anywhere.
Is this ALWAYS an indicator of a leaking head gasket, or is there a less expensive & simpler solution?
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I discovered a pin hole leak in the radiator today (5/31/16). This explains the bubbles and mysterious loss of coolant!
The system couldn't drink from the overflow tank because it was sucking in air through the pin hole. The pin hole was near the TOP of the rad so the leak was hard to notice. It was an intermittent leak. Live & learn!
Thank GOD no head gasket leaks!!
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I thought about solder, but there was SO MUCH internal corrosion (due to neglect from the PO), I didn't think solder would work.
I tried epoxy (which would adhere to the uncorroded outside surface of the tank). This didn't work. As soon as the cooling system developed pressure during initial engine warm up, the hot pressurized coolant spewed right past THREE LAYERS of cured epoxy.
To avoid buying a new radiator (at $425) I bought a used one on eBay for $75. I will see how this works.
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Update: I just installed the used radiator (6/7/16). Good news - The rad is LEAK FREE! I warmed up the engine (electric fan turn on), the coolant level in the reserve tank increased (by like 1/2") , the engine warmed up fast, there are no visible leaks anywhere. NOW this engine can run at normal operating temperature & cooling system pressure!
After a long hard test ride tonight that included a mixture of high & low speed, I shut of the engine & inspected the bike with a flash light.
I then noticed a small stream of bubbles within the coolant in the overflow tank.
Also, the level of coolant in the reserve tank does not increase & decrease with thermal cycling of the engine like it should.
Also, there is a mysterious loss of coolant (only about 2 cups) over 3 days of riding. There are no visible coolant leaks anywhere.
Is this ALWAYS an indicator of a leaking head gasket, or is there a less expensive & simpler solution?
-------------
I discovered a pin hole leak in the radiator today (5/31/16). This explains the bubbles and mysterious loss of coolant!
The system couldn't drink from the overflow tank because it was sucking in air through the pin hole. The pin hole was near the TOP of the rad so the leak was hard to notice. It was an intermittent leak. Live & learn!
Thank GOD no head gasket leaks!!
-------------
I thought about solder, but there was SO MUCH internal corrosion (due to neglect from the PO), I didn't think solder would work.
I tried epoxy (which would adhere to the uncorroded outside surface of the tank). This didn't work. As soon as the cooling system developed pressure during initial engine warm up, the hot pressurized coolant spewed right past THREE LAYERS of cured epoxy.
To avoid buying a new radiator (at $425) I bought a used one on eBay for $75. I will see how this works.
------------
Update: I just installed the used radiator (6/7/16). Good news - The rad is LEAK FREE! I warmed up the engine (electric fan turn on), the coolant level in the reserve tank increased (by like 1/2") , the engine warmed up fast, there are no visible leaks anywhere. NOW this engine can run at normal operating temperature & cooling system pressure!
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