Post by wayne on Mar 29, 2020 18:28:22 GMT -5
The original post by AP951 and all comments can be viewed here: re5rotary.proboards.com/thread/1118/petcock-fuel-tap-fix
This post can also be found under "Restoration"
There are certain components of the RE5 petcock which are no longer available. Even replacing all the rubber components will not necessarily fix a leaky petcock as the seat for the O ring sealed vacuum line may itself have deteriorated and be near impossible to clean up. Fuel slowly leaking into the carby is often a major contributor to the hard starting experienced between rides, particularly if the layup has been weeks or months. You can replace the petcock with an alternative (see below for "Solution 2"), try this solution for repairing the original (see below for "Solution 3") or you can modify the original:
Solution 1:
The following fix is by board member AP951. This fix works and several members have used it.
I want to share a fix that I came up with last spring. After many attempts I could not repair the vacuum leak internal to my petcock & when parked it would always weep gas into the carb. I decided that I no longer wanted the vacuum-open/spring-closed action of the stock unit. I really wanted it to work like the petcocks on my other old bikes. The stock Re5 petcock has 3 settings: Prime-Open-Reserve. I came up with a fix that converts this to: Closed-Open-Reserve.
I removed the plate in the back & used it as a template to fabricate a brass plate that I used to replace the sock plastic unit. For this I purchased a piece of .062" thick brass plate from my local hobby store. You can use other materials/thicknesses however I chose this because I'm partial to brass & it was easy for me to work with. I used a sharpening stone to lap all of the surfaces flat. I also purchased some good quality gasket material & fabricated two gaskets. (again using the stock plate as a template)
I used a small wire brush on my Dremel to thoroughly clean out the cavities on the backside of the control knob. I used JB weld (a little lean on the hardener to keep it more fluid and resist air bubbles) to fill the cavity that is shaped as the radius. Again I used a sharp file to remove the access and then lapped the surface to a smooth flat finish. I replaced the seal behind the knob with a new one and put a very light coating of anti-seize compound on all of it's surfaces. This will make the knob turn smooth & easy.
I reassembled the unit leaving out the stock plastic plate with it's diaphragms & spring. The petcock now works like a conventional unit: Closed-On-Reserve. I still run my vacuum line so the bike looks completely original. An added bonus is that the fuel flows much better as the stock diaphragm internals are restricting to the fuel flow & as many here know Re5's are thirsty. After a year I took it apart to inspect & the JB weld has not changed at all. When this is turned to the closed position it does not leak one bit.
Solution 2:
From member Rotorious:
Here is a petcock that will fit and work and is still available. Suzuki Part Number 44300-45011. You'll need to file the opening in the tank just a little bit to widen it or remove the screen filter. You'll also need to cap the priming outlet on the tank as this one is integral to the petcock.
Solution 3 :
The problems with the leaking petcock have in the past boiled down to the unavailability of the critical "O" ring. The clover leaf gasket is still available. Even when a similar O ring can be found, the problem often lies with the poor condition of the seat that the O ring works in. Read on.
From FB member Colin Packer, March 2020:
A few weeks ago I was working on resolving the age old petcock dripping issue. Suzuki doesn't sell the o ring that attaches to the diaphragm and shuts off the flow. But Kawasaki does. The part number is 92055-044. (The diaphragms are different, sorry).
I've looked at using other o rings such as ones from small Suzuki carburetors or Harbor Freight assortments. They may work but the dimensions are not right. My diaphragm was intact so I installed the o ring, honed the seat using 2000 grit sandpaper attached to a pencil shaped to match the angle of the seat. I also assumed the spring had compressed over the years so I stretched it from 14mm to 17mm in length for some extra force on the o ring. I'm happy to report not one drop leaks from my RE5 or my GT500. I'll probably still clamp the fuel line when towing but it seems to fix the leaking/flooding/smoking issue on start up.
This post can also be found under "Restoration"
There are certain components of the RE5 petcock which are no longer available. Even replacing all the rubber components will not necessarily fix a leaky petcock as the seat for the O ring sealed vacuum line may itself have deteriorated and be near impossible to clean up. Fuel slowly leaking into the carby is often a major contributor to the hard starting experienced between rides, particularly if the layup has been weeks or months. You can replace the petcock with an alternative (see below for "Solution 2"), try this solution for repairing the original (see below for "Solution 3") or you can modify the original:
Solution 1:
The following fix is by board member AP951. This fix works and several members have used it.
I want to share a fix that I came up with last spring. After many attempts I could not repair the vacuum leak internal to my petcock & when parked it would always weep gas into the carb. I decided that I no longer wanted the vacuum-open/spring-closed action of the stock unit. I really wanted it to work like the petcocks on my other old bikes. The stock Re5 petcock has 3 settings: Prime-Open-Reserve. I came up with a fix that converts this to: Closed-Open-Reserve.
I removed the plate in the back & used it as a template to fabricate a brass plate that I used to replace the sock plastic unit. For this I purchased a piece of .062" thick brass plate from my local hobby store. You can use other materials/thicknesses however I chose this because I'm partial to brass & it was easy for me to work with. I used a sharpening stone to lap all of the surfaces flat. I also purchased some good quality gasket material & fabricated two gaskets. (again using the stock plate as a template)
I used a small wire brush on my Dremel to thoroughly clean out the cavities on the backside of the control knob. I used JB weld (a little lean on the hardener to keep it more fluid and resist air bubbles) to fill the cavity that is shaped as the radius. Again I used a sharp file to remove the access and then lapped the surface to a smooth flat finish. I replaced the seal behind the knob with a new one and put a very light coating of anti-seize compound on all of it's surfaces. This will make the knob turn smooth & easy.
I reassembled the unit leaving out the stock plastic plate with it's diaphragms & spring. The petcock now works like a conventional unit: Closed-On-Reserve. I still run my vacuum line so the bike looks completely original. An added bonus is that the fuel flows much better as the stock diaphragm internals are restricting to the fuel flow & as many here know Re5's are thirsty. After a year I took it apart to inspect & the JB weld has not changed at all. When this is turned to the closed position it does not leak one bit.
Solution 2:
From member Rotorious:
Here is a petcock that will fit and work and is still available. Suzuki Part Number 44300-45011. You'll need to file the opening in the tank just a little bit to widen it or remove the screen filter. You'll also need to cap the priming outlet on the tank as this one is integral to the petcock.
Solution 3 :
The problems with the leaking petcock have in the past boiled down to the unavailability of the critical "O" ring. The clover leaf gasket is still available. Even when a similar O ring can be found, the problem often lies with the poor condition of the seat that the O ring works in. Read on.
From FB member Colin Packer, March 2020:
A few weeks ago I was working on resolving the age old petcock dripping issue. Suzuki doesn't sell the o ring that attaches to the diaphragm and shuts off the flow. But Kawasaki does. The part number is 92055-044. (The diaphragms are different, sorry).
I've looked at using other o rings such as ones from small Suzuki carburetors or Harbor Freight assortments. They may work but the dimensions are not right. My diaphragm was intact so I installed the o ring, honed the seat using 2000 grit sandpaper attached to a pencil shaped to match the angle of the seat. I also assumed the spring had compressed over the years so I stretched it from 14mm to 17mm in length for some extra force on the o ring. I'm happy to report not one drop leaks from my RE5 or my GT500. I'll probably still clamp the fuel line when towing but it seems to fix the leaking/flooding/smoking issue on start up.