GL1500 carb question

[C5Performance]

So GLWrench and I were fixing a really bad carb leak today. We pulled the carbs, cleaned them off, and gave it a nice baby powder treatment.
We found BOTH carb bowls leaked at the mating surface o-ring. After replacing them and checking for leaks again we found the problem fixed.

Our question to each other was "why did both start leaking at once"? Has anyone seen this? GLWrench has been a Goldwing exclusive repair shop since they started making them, but these carbs were leaking so bad it was a steady drip. All bowl screws were tight.

Ideas??

 

[joedrum]

hmmmm

 

[dan filipi]

I know nothing about the 1500 carbs but what if let's say the carbs got overheated?
Or some cleaner ran through them or got sprayed on the seal?
Could that damage both seals?
Were the seals hard?
Any other oddities with this carb set?
With the engine they came from?

 

[C5Performance]

There is a large rubber mat over the engine which reduces engine heat in the carb area. This mat had been removed previously.

The o-rings didnt look bad, no tears, and the bike had been worked on by GLWrench but not recently.

We thought maybe excessive heat caused o-ring hardening or even shrinkage from the heat shield being removed, but we are in Wisconsin so it never gets much over 90 degrees even in the summer. Like I mentioned, the bowl screws were all tight.

I would love to blame corrosive fuel, but the accelerator pump was not leaking and fuel lines all looked good. These carbs lie in the bike horizontally so when you look down from the top you see the slides and needles. The bowl surface is at a 45 degree angle. Odd setup but they work good.

GL1500 uses twin carbs, and the Valkyrie (see GLWrenches album) uses six carbs. I pulled them out with direction from GLWrench and we troubleshot the leaks together. It just seems odd they both started leaking at the same time.

 

[mcgovern61]

My opinion (for what it is worth) is that it seem the o-rings may have been crushed from over tightening?

 

[brianinpa]

Is it possible the wrong diameter o ring was used in the past?

 

[C5Performance]

The o-ring matches Honda, with a groove on just one side. Over tightening perhaps, but the carbs haven't been out for at least a year. GLWrench is the only one who works on this bike.
The bowls fit so tight against the carb body you can't really see the o-ring. They are down in a groove. Maybe the o-rings dried out from our long Winter storage due to snow.
Once they started to leak, it could have taken all summer for it to show up as fuel dripping on the garage floor?

So far they are holding fine, and tomorrow morning we put them back in. Hopefully with no additional leaks in the future!