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Discussion Starter #1
So I had a gas cap from a gas container fall in the tank awhile ago, so I finally got around to removing the tank and dangling the tank upside down till the cap popped out. I did a paint swirl remover before I sat it back on the bike for reassembly, so I took the gas cap off the tank that is held with two screws.

after connecting the hoses back At petcock and The two at bottom rear base of the tank, I filled the tank with gas and started the bike. She turned on as normal, but when riding I noticed the revs would stick after warming up. Eventually when at idle, shed sound like she was starving for gas and if I let idle long enough she’d die on me. I turned back home and had to ride the clutch a lot to get through the ride. When I got home I noticed gas leaking on the bottom of the left carb.

I’m wondering if the gas cap on top of the tank is not sealing right?

Or if I am pinching a hose line when I put the tank back on?


worse case I’m wondering if there is a crack anywhere letting gas seep through.

before I took the tank off, everything was fine. The only repair I did was swap the cam tensioners for manual ones. Other than that, not sure what could be causing

I thought I may have swapped the petcock fuel lines in reverse by accident so I tried swapping them... but I’ve read it doesn’t really matter, so long as the vac line is correct, hehe.

any advice would be great. I’m new to the forum and looking forward to coming here for help or eventually to give a hand. Thanks ya’ll!
 

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You can try carefully tapping on the side of the carb, or look up "the blowback method", a pinned thread in the carb section.

Did you have the fuel lines removed at the carbs? Make sure it's not just a hose leaking.
 

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Discussion Starter #5
You can try carefully tapping on the side of the carb, or look up "the blowback method", a pinned thread in the carb section.

Did you have the fuel lines removed at the carbs? Make sure it's not just a hose leaking.
Where exactly would I be tapping on the carb? The hoses were only removed at the petcock
 

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Where exactly would I be tapping on the carb? The hoses were only removed at the petcock
On the lower half, just hard enough to create vibration that can shake the float loose.

The back blow method creates pressure in the carb that can dislodge a stuck float.

 

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Discussion Starter #7 (Edited)
I took off the tank first and am working on making sure connections were made correctly. Which carb fuel line goes to first left nipple on the petcock?

once I have it connected correctly I’ll try carb cleaner inside to try and clean any gunk that may or may not be causing a stuck float on the front carb... Then I’ll do the Back Blow cleaning. I just find it strange the leak from the front carb started after I reassembled the tank. Could be a freak coincidence, but I think it has to do with that...

UPDATE::
I figured out the factory setting for fuel lines, and the fuel hoses look good. No kinks. I’m wondering if my tank vents are blocked somewhere along the lines... in the tank or possibly all the way to air box. Can this create a gas leak at front carb?
Any test or cleaning method stickies? Thanks for the help gents!
 

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It won't be a clogged vent, that usually stops fuel from flowing.

If the carbs dried out while you had the tank off, that can lead to the float sticking.
 

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Discussion Starter #9
It won't be a clogged vent, that usually stops fuel from flowing.

If the carbs dried out while you had the tank off, that can lead to the float sticking.
Well, in any event I found a kink in the tanks right air vent that goes to a circular black joining contraption. Two hoses coming out the top, with labels on the side for “from tank” and from carbs. I pulled tight on that when I was putting things back together, that’s when it got kinked. I’ll continue with finger pointed to the stuck float. If anyone has anything else to add?... meanwhile I’ll be finishing up with the advice given so far.
 

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Discussion Starter #10 (Edited)
On the lower half, just hard enough to create vibration that can shake the float loose.

The back blow method creates pressure in the carb that can dislodge a stuck float.

Thanks for your help Spockster. One last question.... how does the carb drain outlet look like, so I know I am putting a hose and blowing in the correct spot. First time working with carbs, but I'm learning. A picture would really seal the deal. Is it the same part that the hose to the petcock is connected to? I keep seeing everywhere saying it is at the very bottom... underneath? I'm going to go look again for this spot. Wish there was a quick 10 second vid out there... If I can learn where it is I can make a quick video and add it to the sticky thread, so everyone can have a word and visual explanation.
 

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Yes, it's a small hose nipple under the bottom of each carb. There's a screw at the bottom pointing out to the side that opens the drain.

I think there should be pics in the manual. Link to download the manual in my signature.
 

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Discussion Starter #13
Awesome, so I did the front carb and didn't notice any change when running the bike. It started to leak again and bogging down when lurking and moving at slow speed... but I looked on the other side and noticed I could be looking at the rear carb and not the front carb, which would point the leak area to the rear carb. So I'll try the rear carb in the morning with the blow back method.

I noticed the sticky instructions say I need to remove the carb intake boot as well? Is that really necessary, will it not work if I leave it on and follow the rest of the instructions? It looks pretty hard to reach in there and unscrew the clamping bracket around the boot. is it the bottom boot that connects from the engine to the carb underside? Or is it the boot at the top that is much bigger?

I feel like I'm getting somewhere closer to figuring this out. I'd like to do everything I can without opening up carbs, FIRST. Part of owning a bike, get yer hands dirty and do the work correctly.
 

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Removing the boot is probably in case fuel gurgles into the intake. Just be aware it might be flooded when you start it the first time, might need to open the throttle.

Removing the boot probably isn't necessary, there should only be a small amount of gas.

Where exactly are you seeing the gas coming out?
 

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Discussion Starter #15 (Edited)
Removing the boot is probably in case fuel gurgles into the intake. Just be aware it might be flooded when you start it the first time, might need to open the throttle.

Removing the boot probably isn't necessary, there should only be a small amount of gas.

Where exactly are you seeing the gas coming out?
I drained the carb before blowing anyway... but glad to know I don’t have to remove any boots. I’m seeing gas buildup/trickle on the bottom spring mechanism that sits at the bottom and in between both carbs. The visible spring has some yellow paint on it, and looks like a pulling arm is connected to it. Also seeing it trickle and collect at the front carb, collecting at the bottom corner of the casing, the corner under the plastic circle that houses the rubber circle valve. I believe it’s collecting there because the bike is tilted in that direction due to being on the kickstand.
Here is a photo of someone else’s bike, with a circle around the first area of gas leaking.
52942
 

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Discussion Starter #16
Removing the boot is probably in case fuel gurgles into the intake. Just be aware it might be flooded when you start it the first time, might need to open the throttle.

Removing the boot probably isn't necessary, there should only be a small amount of gas.

Where exactly are you seeing the gas coming out?
Random thought, I have a roommate who hates me because of my views and beliefs... he knows a little about bikes... something got me thinking he may have turned the air/fuel mixture screw just to mess with me, he always sees me doing work on the bike, and he goes out late at night to "hang in his car"

Could a bad setting on either carb cause the symptoms I'm having?

When I let the bike idle it goes between almost dying to revving up to 2k rpm, sticks there for a minute then goes back to almost dying... all while leaking in said area.

Just thought I'd ask.
 

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Interesting living situation.... regardless, the A/F mixture screws are covered on these carbs unless you took the time to remove the lead plugs to get to them. If they’re uncovered already and you think that’s a possible cause, lightly tighten them all the way in and then back them out 2 full turns. Only the idle screw with the little black plastic knob is exposed normally.
Also, the spot you have circled is the throttle assembly, that’s strictly a mechanical point on the carbs and there is no fuel in that specific spot. Try to dry everything off and then start trying to pinpoint where the fuel is dripping out from.
 

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Stuck float. Carb is overfilling and the gas is leaking from the shaft on the butterfly, the throttle plate shaft.

I would try the blowback with gas in the carb. That way, the float can float back up when it moves. Without gas it's just hanging in the stuck open position.

Wouldn't be surprised to find there's gas in the oil now. So if it's over full, it needs an oil change.

Also a chance there's an air leak, but get the flooding stopped and see how it goes.
 

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Discussion Starter #19 (Edited)
Stuck float. Carb is overfilling and the gas is leaking from the shaft on the butterfly, the throttle plate shaft.

I would try the blowback with gas in the carb. That way, the float can float back up when it moves. Without gas it's just hanging in the stuck open position.

Wouldn't be surprised to find there's gas in the oil now. So if it's over full, it needs an oil change.

Also a chance there's an air leak, but get the flooding stopped and see how it goes.
If I leave the drain closed, wouldn't blowing through the bottom nipple do nothing? And when if I try with the drain open on a full carb, wouldn't gas come gushing through the nipple I need to blow from? How would I accomplish the blowback with gas still in the carb? I'm not afraid of getting gas in my mouth, just clarifying lol.

Also, I have fresh oil on standby and don't plan on driving her till its fixed.
 

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You need to put the hose on the carb, apply some pressure in the hose while opening the drain.

With just air in the carb the float won't float, just hang there.

Just to clarify... There's no adjustment anyone could do to cause this problem, they would have to take the carbs apart first.
 
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