Chasing a coolant leak on my 2000 GL1500SE 55,000miles. Coolant pooling on top of cylinder block left front. Likely from the large coolant pipe connecting the head to the thermostat housing.
Question number one. The old o-rings were flat due to age. New ones appear to have a stepped sealing surface and appear to be directional. See picture. I did not find the answer in my repair manual. Is this the correct direction for installation?
Question number two. Are there any other common or likely sources for a leak in this area?
1. I've not seen the new stepped o-rings. Are they from Honda? I would think that is the correct install direction.
2. Have you checked the coolant lines into and out of the carbs?
How about the coolant reservoir tube and right angle elbow?
There is also a short connector hose between the 2 radiators to check.
The leak I had in the same place was from the O rings that you are replacing. I have not seen that type of O ring either. I would install it like you are doing. It is a Honda one? If not, remember, everything is metric on these bikes. A standard O ring is a different size and will not seal up right.
The orings I am installing are OEM Honda. The old ones appear to have been stepped at the beginning of their life. I have ordered every small coolant hose excluding the main radiator hoses. This is a nasty job. The worst I have encountered on any bike. Lots of tupperware removed, Carbs and intake manifolds also. With 22 years of age I am trying to avoid having to go back in for a repeat performance.
