How To : Installing A Manual Fuel Petcock

[90GTVert]

Installing A Manual Fuel Petcock

Remove the fuel and vacuum hoses. Make sure you have a catch pan handy when you remove the fuel line.


Unscrew this nut, keeping a large catch pan under the area. If you completely remove the unit, fuel will flow out pretty fast. Of course you should wear hand and eye protection, no open flames, etc...


Here's the whole assembly. You pull the fuel filter to remove it and push to reinstall. Just be sure it is seated properly. There is a rubber sealing ring in the nut as well (which I never took a pic of), make sure you don't lose it.


Here's the outlet of the fuel tank.


The way you install a manual petcock will vary depending on your application. What I've shown is what worked on my Triton. There are thread on replacements for some scooters that will install just like your original vacuum unit. Some folks are using 3/8" NPT fittings to thread onto their gas tanks and remove the vacuum petcock, yet I couldn't find anything to work in the local hardware store that was the same thread as mine. I decided to pick up some 3/8" NPT fittings anyway.

Here is what I grabbed to try.


I bought two of these fittings with an alternative solution in mind, and it seemed to work out. I used a piece of 1/2" fuel hose and 2 hose clamps to attach the tank's outlet to a 3/8" NPT male to female 90 degree elbow. Then I used a 3/8" NPT to 1.4" hose barb. I used 1/4" Tygon hose, a manual petcock, the same Spectre fuel filter I was using, and some hose clamps to complete the fuel line. If you do this, you'll also need to put a vacuum cap on the vacuum port of the carburetor.

This is very ugly. I hate the way it looks, but at least it's not a vacuum petcock anymore. Maybe I'll do something better later, dunno.




It's a pleasant change to simply open the manual fuel petcock and watch fuel instantly fill the line and filter.

[dr1445]

the gas tank on my triton had a 14mm fitting, i was able to run a 1/4 pipe die down the fitting. now i can use common 1/4 pipe fittings.

[rupert]

Re : 2005 Yamaha Zuma : The stock vacuum petcock is replaceable with a manual one from a Yamaha Raptor.

[90GTVert]

Fuel hose and petcock replacement (TaoTao ATM50-A1) :

www.youtube.com/watch?v=QCskx5LO33c

[2TDave]

Here's a pic of the fuel tap I used. I tapped the inside this time to 1/8 npt and found a 1/8 npt 1/4" hose barb 90* at Ace Hardware. Ace was my last stop after gathering a collection of brass and bronze and some 5/8" fuel line. $55 worth of crap I returned but wanted to make sure I had what I needed and I had 3 different mouse traps in mind. Here's what I ended up with after deciding to try Ace when I wasn't happy with 2 lbs of fittings on my tank.

[90GTVert]

Another option is to remove the stock threaded on petcock. Then measure the inside diameter of the nut on the shutoff and outside diameter of the fitting on the tank to figure out the thread diameter. Measure the distance between threads, the thread pitch/spacing. If you have a thread file, you may be able to use that to match up the thread pitch. Then use that info when searching sites like eBay, amazon, PFS, etc... to find something that matches what you found. The new petcock should install just like the old one, minus the vacuum line that will need to be removed and capped off.