Hi all,
I bought my '79 GS750(N) back in April and have been plugging away at all the maintenance items recommended by this lovely forum, BikeCliff's references, and in the manual, and have come across my first problem that I couldn't find a definitive answer to on the forum!
The problem:
There is a slow weep of fuel past the float bowl gaskets on at least three of my four carbs. I can tell it is coming from here and not the fuel tee / nipples above because all surfaces of the carb body above this are dry, but a shiny, almost condensation-like film of fuel originates at the top of the bowls, and the gaskets are darkened showing saturation.
Details:
I am not the first owner, and do not know the maintenance history of the bike. That being said, it was with the original owner for most of its life, it mostly sat since at least 1994, and the trunk that was attached contained a variety of empty Suzuki OEM part bags, none of which relate to the carbs (this and the fact that the dealer tag was still on the keys gives me at least a little hope that it's mostly original). I have completely disassembled my carbs, and methodically cleaned each one individually utilizing the Harbor Freight ultrasonic cleaner w/ distilled water & a splash of Simple Green Pro HD, and carb cleaner to verify flow through all passages & orifices. I utilized the flat edge & the dull point of a dental pick to clean the body gasket mating surfaces, and chased either side of the raised sealing groove to remove any debris built up on either side, respectively. I followed Paul Musser's 2005 VM rebuild guide, replacing all o-rings and gaskets (Thanks Nessism for the o-ring kit), except for the cover gaskets as they're in pretty good shape and came off cleanly. The float bowl gaskets are OEM Suzuki, purchased off of Ebay (unsure of age, the bag looks un-yellowed, but the gaskets are fairly stiff, wish the bag had a date code). All o-rings were installed with a touch of oil to ease installation, but the gaskets were installed dry. The floats were set to the manual's recommended 25-27mm, with most of them being between 25-26mm (which I assume would mean on the lower end of the fuel level). The bowls were attached using the original Philips screws, tightening each bowl in an x-pattern, repeated passes, tightening pretty hard (until it felt the Phillips heads might deform). After reassembly I placed the carbs, level, on a block in a container, to check for leaks. Everything looked good, except the float bowl gaskets.
Did I tighten the bowls too much, possibly warping the carb bodies? Are the OEM gaskets not what they used to be, possibly due to age if NOS? I understand the argument of checking float levels (I plan to) to ensure the fuel level is below the mating surface, but surely the gaskets aren't meant to wick or leak fuel if it's not perfectly level & still (i.e. riding or on kick stand)? Also, I am not getting any fuel coming out of my overflow tubes (which are not clogged).
Any suggestions or assistance is highly appreciated!!
Thanks,
Danny
I bought my '79 GS750(N) back in April and have been plugging away at all the maintenance items recommended by this lovely forum, BikeCliff's references, and in the manual, and have come across my first problem that I couldn't find a definitive answer to on the forum!
The problem:
There is a slow weep of fuel past the float bowl gaskets on at least three of my four carbs. I can tell it is coming from here and not the fuel tee / nipples above because all surfaces of the carb body above this are dry, but a shiny, almost condensation-like film of fuel originates at the top of the bowls, and the gaskets are darkened showing saturation.
Details:
I am not the first owner, and do not know the maintenance history of the bike. That being said, it was with the original owner for most of its life, it mostly sat since at least 1994, and the trunk that was attached contained a variety of empty Suzuki OEM part bags, none of which relate to the carbs (this and the fact that the dealer tag was still on the keys gives me at least a little hope that it's mostly original). I have completely disassembled my carbs, and methodically cleaned each one individually utilizing the Harbor Freight ultrasonic cleaner w/ distilled water & a splash of Simple Green Pro HD, and carb cleaner to verify flow through all passages & orifices. I utilized the flat edge & the dull point of a dental pick to clean the body gasket mating surfaces, and chased either side of the raised sealing groove to remove any debris built up on either side, respectively. I followed Paul Musser's 2005 VM rebuild guide, replacing all o-rings and gaskets (Thanks Nessism for the o-ring kit), except for the cover gaskets as they're in pretty good shape and came off cleanly. The float bowl gaskets are OEM Suzuki, purchased off of Ebay (unsure of age, the bag looks un-yellowed, but the gaskets are fairly stiff, wish the bag had a date code). All o-rings were installed with a touch of oil to ease installation, but the gaskets were installed dry. The floats were set to the manual's recommended 25-27mm, with most of them being between 25-26mm (which I assume would mean on the lower end of the fuel level). The bowls were attached using the original Philips screws, tightening each bowl in an x-pattern, repeated passes, tightening pretty hard (until it felt the Phillips heads might deform). After reassembly I placed the carbs, level, on a block in a container, to check for leaks. Everything looked good, except the float bowl gaskets.
Did I tighten the bowls too much, possibly warping the carb bodies? Are the OEM gaskets not what they used to be, possibly due to age if NOS? I understand the argument of checking float levels (I plan to) to ensure the fuel level is below the mating surface, but surely the gaskets aren't meant to wick or leak fuel if it's not perfectly level & still (i.e. riding or on kick stand)? Also, I am not getting any fuel coming out of my overflow tubes (which are not clogged).
Any suggestions or assistance is highly appreciated!!
Thanks,
Danny
