Coolant Leaking out of cap


Information and questions on GL1100 Goldwings (1980-1983)
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lgsparks1
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Motorcycle: 1980 Goldwing GL1100I

Coolant Leaking out of cap

Postby lgsparks1 » Sat Mar 28, 2015 6:45 pm



Over the past couple of months I have done many projects on my bike. One being, remove radiator and take to local shop, replace thermostat and replace coolant with new. I am learning that sometimes you should just leave well enough alone! Bike never lost coolant or over heated before, but now crap!
Bike gets no were near overheating but everytime I ride 20 plus miles I leak coolant out of a brand new cap. I have checked 2 year water pump_ GOOD!!! I filled and ran with cap off to get air out of system. Fan comes on when it should but seems to run longer than it should. Old cap never leak but replaced with another identical aftermarket stant cap , just like what has been on it for 4 years.


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lgsparks1
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Re: Coolant Leaking out of cap

Postby lgsparks1 » Sat Mar 28, 2015 6:47 pm

More info the thermostat is not Honda but a Napa 101. 180 degree aftermarket and no I have not tore it back down to check it.
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Aussie81Interstate
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Re: Coolant Leaking out of cap

Postby Aussie81Interstate » Sat Mar 28, 2015 7:35 pm

May not be the cap - but the overflow pipe feeding to it

how is the level in the overflow tank?

might be worth taking the tank shelter off to have a look?

or the cap not on securely ??

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lgsparks1
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Re: Coolant Leaking out of cap

Postby lgsparks1 » Sat Mar 28, 2015 7:59 pm

Overlfow hise is brand new, tube inside of overflow tank is brand new, both are free and clear. Cap is on securely.
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Dave N
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Re: Coolant Leaking out of cap

Postby Dave N » Sun Mar 29, 2015 10:10 am

Take a look at the old cap gasket, I tried putting new cap on and it leaked. I found out that the new cap gasket was just a little smaller then old cap. Put old cap on and no leak.

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lgsparks1
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Re: Coolant Leaking out of cap

Postby lgsparks1 » Sun Mar 29, 2015 11:56 am

Unfortunately old cap was aftermarket as well and new cap is exact replacement for the cap that was already on the bike.
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WingAdmin
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Re: Coolant Leaking out of cap

Postby WingAdmin » Mon Mar 30, 2015 9:33 am

The coolant system is supposed to be pressurized - that's why it can be at more than the boiling point would be at atmospheric pressure, without boiling. It's also why people get badly scalded/burned when they remove a hot radiator cap: the superheated coolant sprays out and instantly boils upon encountering the lower (atmospheric) pressure.

It's the job of the radiator cap to regulate this pressure, allowing coolant into the overflow tank when the pressure gets too high. It's the job of the gasket in the cap to seal the radiator. It sounds like this gasket is leaking on your bike. Being aftermarket, you may have to improvise to fix it. Check the neck of the radiator filler to make sure it is flat and even and makes good contact with the gasket. If it isn't, you might have to find a thicker gasket to put in place in the cap.

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lgsparks1
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Re: Coolant Leaking out of cap

Postby lgsparks1 » Mon Mar 30, 2015 9:52 am

Thanks wingadmin. I think on this one I am going to just cough up the extra cash and order the Honda OEM cap.


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