How To Test A Vacuum Operated Fuel Valve

Vacuum operated fuel valves can contribute to MANY different problems that you may face with your carbureted Honda motorcycle. In this video I go over 3 different possible outcomes with how your fuel valve has failed and exactly how to check it. It doesn't get much simpler than this!

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[matblackgraviton]

Dude- people like you are making the internet great again! Thanks for sharing your knowledge out to us plebes.

[clivecarrington]

After I split and cleaned my carburator s on my GL 500 Honda. Rebuilt the carbs, and took me 6 months of fustration rebuilding so many times.
I finally saw your video. Taken it off and cleaned it throughly.
Assembled it and fitted to the bike.
Guess what. Urrika moment.
Thank you so much. Even after 5 years of you making this vid, people profit from you valuable knowledge.
Thank you very much.

[antoniomoreno]

WOW my friend, you explained SEVERAL issues happening now on my 2000 dyna twin cam 88.
Knowledge is power and you are a powerful person!
Thank you for sharing it, with us all, and helping save us all time, headache. And money. People like you my friend this world needs more of. God bless you...

[NorthJorgie]

I'm currently trying to get an 02 kz1000 running that sat for like 2 1/2 years, pulled carbs out, completely nastiness, floats stuck, the works! your videos have helped a lot for sure, thank you.

[scoutydoggers]

Cody you are the man I've had Honda's my whole life and I'm old! I understand the vacuum system on these fuel valves and the one on my 1500 is working good so far but now I understand after you gave that wonderful explanation of what's all involved with that and what to expect! Thank you so much for the videos you are extremely helpful!

[cars]

Hey bro.. let me just say.. not only are you a beast when it comes to this but no one else explains and shows things to the level of detail that you do and straight to the points..

I appreciate you. I had a scooter for work sit for 3 months and went crazy trying to clean the carb... ended up that my fuel pump/peacock valve wasnt working correctly.. i would get gas sometimes and sometimes i wouldnt get any.. i would get enough to fill the lil plastic filter before the carb but not enough to rum the scooter... took me 3 days to find out i wasnt getting enough gas cuz it looked like i was and the bike ran sometimes for a day and then not turn on... lol $6 fixes my issue... any store wouldve charged me the 40 for carb cleaning and goddknows whta else

[isaacaskey]

Great video! I have a go kart that is leaking fuel out of the exhaust, and you have further reaffirmed me that it is this device along with the carb floats. I noticed when trying to start it up, fuel leaks through the vacuum hose. I also noticed that when the go kart isn’t even running, it is leaking fuel out of the exhaust, indicating the carb floats are also a culprit. Thank you so much for this! Very informative!

[brentmcgillis]

I finally have a use for my Vacuum pump that I purchased in order to bleed the brakes on my 4x4 Silverado, and my Yoda Avalon. I did learn how the fuel petcock works, I did not know before watching your video. You did a perfect explanation of how the unit works, and better yet you provided examples of hard to find vacuum leaks and other defective component within the Fuel petcock itself.
I now have the confidence to rip into my Katana 600F, this bike has had quirky fuel issues since the day I bought it online used. The bike did not even run when I bought it, me and my friend Mike bomb started the thing for 1/2hr just so I could ride it home, because I did not have a ramp at that moment. I found your explanation very concise on how the unit "should work." And I really enjoyed the part about hard to find leaks in the system, and what to keep a lookout for in defective parts. Thank you for sharing your knowledge. The Katana has had 3 carb tear-downs and a ultrasonic carb cleaning, and untold # of cans of Seafoam. I unloaded the parts Canon at the bike with brand new aftermarket Coils that come with the plug wires, 2nd set of NGK plugs, a salvaged CDI Ignition box. It ran fine for a couple of years, took it to the car wash and this bike has now turned into the money pit.
Honestly, I really had no idea how problematic these petcocks were, now since I understand how they work after watching this YouTube video, I hope to solve the mystery that has stumped bike shops for 5 years now.

[guitarforlife]

Dude you saved me I doubt you’ll see this since the video is so old but my bike was running ok had some backfiring so I changed plugs started her up again then went back changed oil coolant gear oil air filter sub air filter fuel filter put it all back together haven’t been able to get it to start didn’t even know my petcock pulled a vacuum the manual says something has to be clogged so I’ve been blowing everything out thought maybe the fuel line was air locked pumped fuel into the line by hand was about to give up and take it in and just found this video you sir are a god damn hero

[michaelanderson]

So helpful Cody - I did not know this vacuum valve could cause so many issues.
Great video Sir.

[Hendrix.]

Awesome man..Mine just started running out of gas when the tank got down to about 1/3 filled. I took it apart and stretched the spring and it seems to be working. More testing needed though. It's a 2002 Honda Nighthawk 750.

[Springercycles]

Dude, I appreciate thus video so much, I just rebuild an 500vt and got it back together and the petcock leaking bad. Tried to clean and repair it but everything looks good. Now I know I just need to replace it.

[fatboyfollies]

Man! I wish you were my next door neighbor. I love how you teach this stuff. I’ve done several kinds of fixes successfully from your vids. Well, I guess you are my next door neighbor in that way. Thanks for the great content.

[dannysmits]

Thanks very much for the tip.
I paid €78 for the part with the broken membrane.
The valve was located on the right side of my super Magna, half way cylinder 3.
It was easier to suck it without the tube, since the other end was difficult to reach.
Thanks again.

[wtimber]

I suspect this may be my problem on a Suzuki, I wanted to see how the inside of them worked, not a lot out there, the factory diagrams are not great. From the moment I got this bike I was confused why it had on, pri and res but not a off position. Started leaking gas the first time I filled the gas tank. I noticed the second tube when taking the carb out to send it off to be rebuilt and saw gas flowing from both tubes. Thought nothing of it until I saw the factory manual did say it was a vacuum hose only so that was my first clue. Great video. Still helping people 4 years later.

[Snake]

thank you man iv'e been fighting with card setup issues for 4 days just to find out my fuel tap is ''broken'' and i'm seeing the same symptoms you have described runs fuel out for a bit then stops, i'm going to replace it tomorrow for one that works.

thanks again for the help

[Turbofab]

I see this video is 5 years old, and after taking apart Mt bike and carbs 8 times I was close to scrapping the bike, until I had a funny feeling it was the fuel tap and after watching this I am pretty certain it is,
I've ordered the parts so time will tell,
Thanks alot for the video

[jasonburks]

Great job explaining how everything works, what properly working vs failure looks like, and how to test each case. My vacuum port was somehow completely clogged. Thanks!

[NickellBag]

I'm having this problem with my 96 F3. The vacuum has been changed to a standard flow. So right at the end if your video you said it! Gas getting into my valves n into crank case. So I've done everything else... ECT. My wife said clean the damn carbs. The bike was sitting for over a year. I was trying not to go through all this cause I just wanna scream the BIKE! So looking like carbs are coming off! Thanks so MUCH! I've been working on n racing over half my life. I'm 36 so... I'LL let you know brother! Thanks again

[billleskeep]

Great relevance for this. I attempt to ride nearly everyday and all year long but am always vigilant about this little bugger. I replacement for my 97 1500 Valk is about 50 bucks, an easy amount to spend in light of the havoc it can create if it fails. Well done video, right pace, good framing, spot on.