The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: jgp1854 on August 08, 2012, 07:10:32 AM

Title: 82 LS carb leak
Post by: jgp1854 on August 08, 2012, 07:10:32 AM

Right hand side, minor drip pools at the return spring bracket, and then onto my garage floor!

The carbs were just rebuild by BING a few months ago......I've replaced the bowl gasket with a new gasket, sadly still leaking.  I've check the float needle to no drips and the floats appear to be adjusted properly.  

I'm looking for some insight from this illustrious group, before I remove the right carb and ship back to BING.

thanks as always

Jim

Title: Re: 82 LS carb leak
Post by: donbmw on August 08, 2012, 08:04:07 AM

I  have had a carb bowl develope a pin hole leak. I though it was all of the other items also until i found that.

Don

Title: Re: 82 LS carb leak
Post by: Session101 on August 08, 2012, 08:50:15 AM

pull the bowl and check the floats and float needle, is everything clear? make sure the float height is correct, ive set float heights that were good for about a week then took a ride when the bike was warm and stopped to take a break and started leaking, so i just adjusted the float and all is well, your carb is designed to leak if it has too much fuel in the bowls

Title: Re: 82 LS carb leak
Post by: Bob_Roller on August 08, 2012, 08:54:27 AM

By chance, is the fuel line leaking where it goes onto the fitting at the carb ?

Title: Re: 82 LS carb leak
Post by: jgp1854 on August 08, 2012, 04:55:48 PM

Bob

No, its not I'm using the line recommended by BING, not the OEM fabric wrap.  The BING line is VERY snug fitting.  I have also checked the overflow for "hairline" cracking, using a paper towel, no sign of any issue there.

Any chance the bowl itself could be the problem?  Prior to rebuilding by BING, the LEFT carb leaked, and the right was fine, after the rebuild the right is leaking and the left is good????

I have a set of "rubber" bowl gasket from some outfit in Tennessee/Kentucky, has anyone tried them?  

thanks

Jim

Title: Re: 82 LS carb leak
Post by: jgp1854 on August 08, 2012, 04:58:36 PM

Okay, it just hit me...............what is the proper way to mount the carbs, angled inward a bit to lessen any stress on the cabling, or perfectly parallel to the ground using the base of the carb bowl as the leveling spot????

Jim

Title: Re: 82 LS carb leak
Post by: Bob_Roller on August 08, 2012, 05:33:52 PM

Either way will work, it's up to you .

Title: Re: 82 LS carb leak
Post by: Mike V on August 08, 2012, 06:18:49 PM

JP,

A couple thoughts...

If you're sure the float setting is correct, float needle seating correctly and the leak is not originating from above and running down the fuel line;

1.) Do a quick light hand mill of the bowl cover, just enought to see if the bowl is warped.
2.) Make sure your bowl gasket is not pinched or rolled in the recessed area of the carb body. And make sure the recessed gasket groove is clean of debris and burrs.
3.) Check to make sure the pressed fuel intake nipple (where you slide the fuel line on the carb) is not loose in the carb body or the nipple is not split/cracked.

My personal preference for bowl gaskets are the OEM cork.

Title: Re: 82 LS carb leak
Post by: Bengt_Phorqs on August 08, 2012, 06:40:54 PM

Did Bing supply new floats?  Are they the ethanol resistant type?  During Tom Cutter's seminar at the national rally I learned that the Bing Agency in Kansas is not the Bing Germany.  Some parts are the same and some are not.  I'm not bashing them, have never used either one, and don't have an opinion.  I bought my carb spares from MotoBins and have been very happy.

As for the floats level or not, it just depends on who you listen to.  My airhead guru, Boxers By Bruce, tells me that the BMW factory teaches that the carbs should be vertical, not tilted.