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Did my 1st carb rebuild about a month back, was stoked(and a lil surprised) I got it running better than ever. After more than 1000 miles, gas began leaking from right carb at the joint fuel pipe. Did not use Honda factory O-rings on fuel pipe, so I assumed that was the issue. Took apart the carbs to check it out, but O-rings appeared to look the same. Why is one leaking and the other just fine? Float needle seems good. There might have been a little oil too. Please help! 馃檹
 

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1981 CX500C
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So I actually just came to post a very similar problem. I cleaned the carbs and put the tank back on and everything was fine for a week, left the petcock on the whole time. I'm getting ready to sync the carbs so I took the tank off and made a temporary tank. Once I hooked up the temp tank gas started pouring out at the same spot as you described.

Maybe make sure yours is still attached on both ends.

What I found was that the leak stopped when plugged the vacuum port coming off that right carb. It wasn't hooked up to anything while using the temp tank. I don't really understand why this would cause the leak there but it definitely seems the source of my problem.
 

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1982 CX500C
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Did my 1st carb rebuild about a month back, was stoked(and a lil surprised) I got it running better than ever. After more than 1000 miles, gas began leaking from right carb at the joint fuel pipe. Did not use Honda factory O-rings on fuel pipe, so I assumed that was the issue. Took apart the carbs to check it out, but O-rings appeared to look the same. Why is one leaking and the other just fine? Float needle seems good. There might have been a little oil too. Please help! 馃檹
Did you use lubricant when installing the tube into the carbs? If not it鈥檚 possible the o-ring rolled/twisted while being installed.

Err on the safe side - replace both o-rings again and use lube to install the tube into the carbs. Something greasy (petroleum jelly is what I use) works best but regular oil will do.
 

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'84 CX650E that is evolving into a GL500
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Silicone grease is recommended. Also make sure to clean & polish the pipes and the openings they go into because debris or burrs in them can cause leaks.
I would make sure the new o-rings are the correct size too.

Charles: If your petcock has a vacuum line it is a vacuum petcock, which means it has a vacuum operated valve as well as the manually operated one and fuel can't flow unless the engine is turning fast enough to provide enough vacuum to open the vacuum valve. I have no idea why the leak would stop when you plugged the vacuum line but it would be pointless to balance the carbs with the vacuum line open because it would allow air to be drawn into the engine after the carb.

CXchick:
Welcome to the forum. Please add your location and your bike's model and model year to your profile so that you don't have to remember to tell us every time and we don't have to keep asking when you forget (see Forum Settings link in my signature).

And welcome to the world of antique vehicle ownership (they own us, not the other way around). Your bike is about 4 decades old and the Previous Owners may or may not have done the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual for your model (available through the CX Wiki - link in my signature) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.
I also recommend looking on all rubber parts with suspicion because rubber does not age gracefully. Check the date codes on your tires and replace them if they are over 5 years old no matter how good they look & feel (old rubber simply cannot flow around the irregularities in the asphalt well enough to grip, especially if it is cool or wet). If your bike still has the original rubber brake line(s) (should be replaced every 2 or 3 fluid changes = 5 or 6 years) I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid). And don't forget things like the rad hoses and the boot between the engine and swingarm (they can crack on the bottom where you don't see it).
 
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