Kawasaki Vulcan Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter #1 (Edited)
2000 Kawasaki Vulcan VN800a
33,000 miles.

I have a gas leak on the front side of the carb. Not sure where it is actually coming from. It's not in the air filter nor is it leaking from the gas line. I did notice the petcock does still run out when I take the line off. Reserve runs as well as on. Both lower cylinder areas and top of crankcase gets wet from gas. I changed the oil and filter and when I drained the oil it seemed a lot more than just 3.2 quarts. Could this be a faulty petcock and not a diaphragm gone bad? I did see a couple drips where the small diaphragm is installed tho but not actually sure where it is coming from. I had to take a short piece of fuel line and screw a bolt in it and put it on the petcock to keep it from running out.

I wonder if it is the petcock? On PR it flows. On ,Reserve and On, it drips. About 3 drips per second. That's 180 drips per minute or 10,800 drips per hour. 24 hours equals 259,200 drips! That could cause a pile up of gas and cause a leak to show on the outside.

Thanks to all who help with this situation.
 

Attachments

·
Registered
Joined
·
10 Posts
You have a wonky petcock. There is some very thin gaskets in there as well as an o-ring that degrades over time, so you may as well replace it. I think I read somewhere that you can use a Raptor petcock if you want to go the manual route. If not, use the OEM one - #51023 - 1260, about $100. If you are frugal like me, you can very carefully take it apart and just replace the o-ring. I took it out, went to NAPA and matched it up to a vitron one. Works great. I can't stress enough how careful you need to be. If you rip any of the gasket material, it's toast. Also, you should replace the float needle as well as the motor oil that it probably compromised with gasoline - not good for bearings. Good luck
 

·
Registered
Joined
·
1,160 Posts
with the dial on the petcock set on PRI the gas is free-flow (bike running or not running), with dial on RES the gas uses the last remaining 3 litres at the bottom of the tank (only when bike is running, with bike not running there should be no gas flowing), with dial on ON, the gas flows only when bike is running, with bike not running there should be no gas flowing and no drips, it looks like the little spring inside the petcock is weak and is not fully closing the rubber plug to stop any flow of gas or drips when bike is not running, you can remove the petcock and open up the petcock to get at the spring and gently stretch it a bit to be a little firmer to close the rubber plug, dont stretch it too much, just a little bit to be a little stiffer, otherwise buy a petcock repair kit with all the parts, i think the kit includes a new spring, but check first a spring is included in the kit before buying
 

·
Registered
Joined
·
14 Posts
Discussion Starter #5
I took the petcock off and dismantled it. Stretched the spring out some and reassembled it back together. Installed it back on the tank and put gas back in the tank. It poured out the petcock in all positions. I think I know why tho. As I was dismantling it, I noticed I had to pull a bit to get the stopper on the diaphragm to get it loose from the petcock outlet(?). When reassembling it, I think I should have oiled the O-ring a little and pushed the metal plate to seat it back in place before putting in the screws. I will try this and post how it went latter. This may be why others had issues after rebuilding theirs with a new kit . (Anything is worth a shot!) I am certain I did not tear the diaphragm and I got got it in place with the small posts going thru the small holes in the diaphragm. If possible, I will take pictures and attach them in my next post IF it works.
 

·
Registered
Joined
·
1,160 Posts
as long as the diaphragm is not torn, take the petcock apart and try again
 

·
Registered
Joined
·
14 Posts
Discussion Starter #7
I did tear it apart again and check with a bright light behind the diaphragm and see no tears or extra holes that light shown thru. I put it back together and it slowed down at least but that ain't good enough for me. I am considering ordering the rebuild kit. Any extra instructions for when I receive it before rebuilding?
 

·
Registered
Joined
·
10 Posts
Stretching the spring idea is a good one. I also like to use pure silicon grease on any o-rings, or any other rubber parts when reassembling.
 

·
Registered
Joined
·
14 Posts
Discussion Starter #9
It looks like it may be something else causing the gas leak now. I bought an aftermarket petcock and installed it. (Had to cut the selector down due to it hitting on the bottom of the tank edge to make it work.) With the fuel line off, I put a funnel in a gas container, set it under the petcock to catch any fuel that may leak and poured gas in the tank while the petcock was in the ON position. No leak! I then hooked up all the hoses and rode it to the gas station. Filled the tank up and went inside to pay. When I came out I noticed a hose under the bike was pouring out gas! I pushed it forward and went to crank it but at first would not start. It finally started and I took it back to the house. I placed a container under the hose and watched. No more gas coming out. I put the bike in the shed and still placed the container under it to be on the safe side. I let it set for a couple days and checked it again. There is a wet area around the base of each cylinder. Smelled it and sure nuff, it is gas! Opened the tank and looked in with a flashlight and it is about a gallon lower. I checked the petcock for leakage again and there is no leak in the area or from the outlet. Where is this gas leaking from?? I drained the tank and removed the seat and tank to inspect the hoses and still can find no issues there. The gas is NOT going into the oil either. Could this leak be coming from the accelerator pump chamber? Or could this be a tank that was recalled before? I searched but can not seem to find anything on a 2000 Vulcan VN800A recall on the tank.
 

·
Registered
Joined
·
14 Posts
Discussion Starter #11 (Edited)
I am not sure how sticky floats on a Vulcan like mine would let gas leak when it is sitting for a few days not running. I mean, I can understand it doing so when running but not just sitting. The petcock is supposed to stop fuel flow when not running due to them using a diaphragm that only works to let fuel flow when it is running.

I took the breather section loose and looked behind it and found a hose that the clamp was not on in back of the breather section. It runs to the accelerator pump chamber. I put the clamp back on the hose. Could that have been what was causing this? when the bike runs it seems like there is no issue but I can not look under it for leaks while riding. ;)

The tank has no leaks. I turned the petcock to the ON position and put gas in it. No leak from the petcock. I had the other outlet plugged off. Tomorrow I will take the plug out and see if fuel comes out there. If I am correct, that is from the overfill tube inside. If that is where it is leaking from then I would say I have an unsafe tank that should have been recalled!

I did find a complaint for a 2001 model as stated below.

(Problem with Fuel System Gasoline
Sep 13, 2004 - Olathe, KS - Gasoline, Carburetor System
ON 2 OCCASIONS MY 2001 KAWASAKI VULCAN 800 WAS LEAKING FUEL IN MY GARAGE. HIS MOTORCYCLE USES A KEIHN CVK-36 CARBURATOR. REPLACED GASKET BETWEEN FUEL BOWL AND CARBURATOR BODY AS WELL AS NEW FLOAT, AND NEEDLE. PROBLEM CONTINUED, WHEN MOTORCYCLE SEEPED FUEL ON A NEAR CONTINUOUS BASIS. IDENTIFIED THAT THE ACCELERATOR PUMP DIAGPHRAGM IN THE CARBURATOR HAS FAILED WITH CRACKS AND RUBBER TO MATERIAL SEPARATION. THE PART # KA43028-0002 ITEM 43028A IN KAWASAKI'S PART MANUAL IS $50.99. PARTIAL ROOT CAUSE BEING THAT DESIGN OF THE FUEL TAP. THIS ITEM HAS THREE POSITIONS, ON, RESERVE AND PRIME. THERE IS NOT AN OFF POSITION WHICH I FEEL INCREASES THE FIRE RISK FOR PEOPLE STORING THESE IN THEIR HOME GARAGES. ON MY 2001 VULCAN 800 , THE FUEL TAP VALVE GASKET INTERNAL TO THE FUEL COCK, FAILED DUE TO A PIECE OF OF THE RUBBER GASKET TEARING OFF UNDER NORMAL OPERATION. THIS ALLOWS FUEL TO LEAK OUT WHEN THE MOTOR IS NOT RUNNING. THE FUEL TAP IS DESIGNED TO ALLOW FUEL FLOW WHEN VACUUM IS APPLIED TO THE FUEL COCK. THIS FUEL TAP GASKET IS APPROXIMATELY $6.00 EACH. ADDITIONALLY I HAVE EXPERIENCED 3 PROBLEMS AND HEARD OF NUMEROUS PROBLEMS WITH THE NEEDLE AND SEAT STICKING ON THE VULCANS. GIVEN THE FAILURE OF THE FUEL TAP VALVE GASKET ON MY OWN MOTORCYCLE AND THE FACT THAT THE NEXT COMPONENT IN THE FUEL FLOW IS THE NEEDLE AND SEAT, I THINK THAT THAT MAY BE A ROOT CAUSE. WHEN I DISASSEMBLED MY CARBURATOR I IDENTIFIED SMALL BLACK ITEMS IN THE FUEL BOWL WHICH I BELIEVED TO BE PART OF THE FAILED FUEL TAP GASKET. IT IS UNDERSTANDABLE WHY I AM HEARING COMPLAINTS. THIS FUEL TAP FAILURE IS BETWEEN THE FUEL FILTER AND THE CARBURATOR. HAVING HEARD ABOUT THE REACLL 04V008 FOR 2003 AND 2004 MOTORCYCLES I BELIEVE THE PROBLEM WITH THE ACCELERATOR DIAGPHRAGM STARTED EARLIER THAN IDENTIFIED, AND THERE IS AN ADDITIONAL PROBLEM WITH THE FUEL TAP DESIGN AND MATERIALS.)

Maybe??
 

·
Registered
Joined
·
10 Posts
If it is leaking, then it is a sticking float or something is swimming around in the float bowl and lodging itself between the float needle and the seat. You should probably take the carb off the bike at this point and rebuild or at least take a look see and clean out the bowl area. If the needle is indented, it should be replaced. Something is in there floating around. Kudos to you for replacing the petcock, I never liked the vacuum operated ones, the manual petcocks work better and are easier to rebuild when necessary.
 

·
Registered
Joined
·
14 Posts
Discussion Starter #13
Thank you for your reply Mr. T.

What I do not understand is, how does it make the gas leak past the diaphragm due to a sticky float? I am sure there is a logical explanation to this. The one with the diaphragm worked just fine for 18-19 years.
I thought I was getting a manual petcock but it turned out to be an after market diaphragm type that also let it leak! Today I found one that was brand new and manufactured by Kawasaki for $60.00 (tax included) Ordered it and should be here by weeks end or earlier. Not only did I order the new one but the guy I bought the other one from is sending me my money back so I am only out $44.00 to get this new one. If it leaks after this one then it will be the carb cleaning time. PLUS! An inline fuel filter as close as I can get it to the carb!
 

·
Registered
Joined
·
10 Posts
There is a filter in the tank, but another one probably would not hurt if you can find the room for it. If the petcock is leaking, the float needle/float can't always hold back the pressure. It should, but not always. either way, if it is leaking at the carb, then there is sticky floats(unlikely), something from keeping the float needle from seating, a bad seat, or a worn out needle.
 

·
Registered
Joined
·
14 Posts
Discussion Starter #15
Consider this posting closed!

I now have the issue fixed once n for all. It turned out to be the petcock.
I ordered one that turned out to do the same thing even tho it was brand new. I let the seller know and he refunded my money.
I ordered another that was like the original one except this one was made by Kawasaki. It looks and performs like the original one that was on it.
I installed it,(did not hook up the fuel lines to it) put fuel in tank. No leak in the on position. No leak in the reserve position. The prime position flowed. Used a rag to catch the fuel.
Hooked up the lines, turned it to prime and it cranked right up. Turned it to On and it still ran. Took it for a 5 mile ride. No issue of a leak. Let it set over night and no leak this morning.
I was lucky to not have the gas go into the crankcase. There was no difference in the oil level. I had just changed it and filter before this issue. I am going to change it again just to be on the safe side tho.

IT'S FIXED!! Time for ridin again!

To all that have helped, I would like to leave this issue behind with this to say.

Every solution and idea mentioned is a lesson to be remembered. All are possible solutions to a given situation and should be remembered if anyone else has this issue like I did.
 
1 - 15 of 15 Posts
Top