PDA

View Full Version : Schrader valve adapter



JeepsAndGuns
08-02-2015, 03:07 PM
I am looking for a schrader valve adapter and not having much luck finding one. What I am looking for is a small adapter that one end will thread onto the schrader valve on a fuel rail and the other end be female 1/8npt threads. I have found a couple on google, but they require you remove the valve core and then wrap the threads with tape to make it seal. What I am wanting to find is one that will depress the valve core and also self seal (with a o-ring or something) just like a regular aftermarket fuel injection pressure test gauge.
This would not be for a permanent install, so that's why I am wanting one that will self seal and depress the valve core.

Does anyone know if there is such a thing? I figured if anyone would know, someone here would.
Thanks.

fastacton
08-02-2015, 08:12 PM
Maybe you could modify a fuel pressure test gauge adapter to work for you?

JeepsAndGuns
08-03-2015, 01:55 AM
The one I have, has about a 12 inch piece of hose between the part that threads onto the schrader valve and the gauge. Its all once piece and doesn't come apart. So I would have to sacrifice it or one like it to make something, and they are not cheap. I was hoping to find a premade adapter for a reasonable price and not have to cut one up from a working test gauge.

Xnke
08-03-2015, 03:35 AM
It's a 1/4" flare fitting. You can buy them at air conditioning and refrigeration service places.

1project2many
08-03-2015, 07:47 PM
Yep. What he said. You can still find plenty of old R12 hose sets around to take ends from. I'm not sure what you're doing but you could use this hose, cut off one end, and get an auto parts store barbed fitting with 1/8" pipe to install and clamp.
http://i.ebayimg.com/images/i/281294446803-0-1/s-l1000.jpg

http://www.ebay.com/itm/R12-R22-CAN-TAP-TAPPER-FREON-REFRIGERANT-RECHARGE-HOSE-KIT-/281294446803?hash=item417e74a0d3&vxp=mtr

JeepsAndGuns
08-04-2015, 02:39 AM
Interesting, I had no idea AC lines had the same connections. I might check the local parts store to see if there is something similar. However, I think I have found what I am looking for, after lots of searching.
http://performancefuelsystems.com/products.htm
About halfway down the page.

As for what I am doing? I am planning on making a fuel system diagnostic gauge. Many times I have wanted or needed to check fuel pressure on a vehicle when its being driven. Pressure might be ok at idle, but doing a WOT run down the road the pressure might drop. I tried long ago to add a piece of hose to a "T" and have it stuck under my windshield wiper so I could see pressure driving down the road. But it failed to work.
Now if I get a quality gauge (such as this one http://www.speedhut.com/gauge/GL-FUEL-01/7/Fuel-Pressure-Gauge-0-100psi ) that comes with a quality electronic sender, I could find a adapter to hook to the schrader valve, then just run the wire inside the vehicle, then hook a cig lighter adapter plug onto the power wires for the gauge and I now have accurate real time fuel pressure reading when running/driving. Having the sender on a adapter that just goes on the schrader valve, and powered by vehicles power outlet, makes it super quick and easy to hook up and transfer from vehicle to vehicle.

Six_Shooter
08-04-2015, 03:46 AM
You may still want to use a bit of hose between the adapter and the sender. Some engine bays or engine configurations are sometimes tight around that schrader valve and could cause easy fitment issues. Alternatively you could set it up with quick connects like many test gauges have to make it quickly and easily adaptable to any vehicle.

I like the idea, I may have to make one myself.

1project2many
08-04-2015, 10:08 AM
Electronic is safest.

http://www.ebay.com/itm/52mm-GlowShift-Tinted-Electronic-100-PSI-Fuel-Pressure-Gauge-Meter-Kit-w-Sensor-/351087007487?hash=item51be6a96ff&vxp=mtr
http://www.ebay.com/itm/52mm-Smoked-Blue-Digital-Electronic-Fuel-Pressure-PSI-Gauge-w-Sensor-/371374458574?hash=item5677a486ce&vxp=mtr
http://www.ebay.com/itm/2-52mm-Black-Universal-DIGITAL-BLUE-LED-OIL-PRESS-PRESSURE-GAUGE-Meter-PSI-CAR-/221709349872?hash=item339ee833f0&vxp=mtr

If you don't mind one that says oil instead of fuel there are a bunch to choose from:
http://www.ebay.com/itm/Pressure-transducer-or-sender-100-psi-stainless-steel-for-oil-fuel-air-water-/271576977896?hash=item3f3b3fd1e8&vxp=mtr
http://www.ebay.com/itm/Pressure-transducer-or-sender-100-psi-stainless-steel-for-oil-fuel-air-water-/271576977896?hash=item3f3b3fd1e8&vxp=mtr

IIRC the thread in the rail for installing the Shraeder valve is a standard bolt size. I drilled out the Toyota rail for one but now I can't remember the size. Anyway, it might be possible to put both the Shraeder and the pressure transducer on the engine using a Tee. With that pressure transducer above you could include fuel pressure as an input to your pcm.

JeepsAndGuns
08-04-2015, 02:18 PM
You may still want to use a bit of hose between the adapter and the sender. Some engine bays or engine configurations are sometimes tight around that schrader valve and could cause easy fitment issues.

Didn't think about that, but that is probably a good idea. I have not ordered the adapter I linked to above. Gonna check the local parts store for one of those hoses first. If I have no luck, I may get the hose linked to above.

1project, I have not decided on a gauge just yet, I just linked to the one above as a example. I don't want to buy the most expensive top of the line gauge cause I wont be using it every day. But I do not want to go too cheap because I worry about its quality and accuracy. A happy medium would be fine.

JeepsAndGuns
08-06-2015, 02:11 AM
I looked at the parts store today on lunch for a ac hose like pictured above, but no luck. I did find one of the yellow hoses from a broken ac manifold gauge set at work. I tested it on my fuel rail and it does not fit. The ac hose threads are too big.
However I got thinking, once I make this test gauge, my old one that has a mechanical gauge and a short hose on it becomes obsolete. I saw the exact same one at the parts store and realized it was not as expensive as I thought it was (bought it years ago). So I might just go ahead and sacrifice it to make my new one. The place I linked to above wanted $13 to ship a $17 part that would fit in the smallest padded envelope and ship for a buck or two. :mad1:

JeepsAndGuns
03-08-2016, 03:28 AM
So I finally got around to making this. I ended up sacrificing my old mechanical gauge. I removed the gauge and replaced it with the sensor. I then shortened the hose a bit. I still have plenty of hose left if I need to make it longer. I bought a electric gauge off amazon that had pretty decent reviews. I like it because it has both a pointer and a digital readout. It also came with the sensor. I picked up a power pigtail at napa and wired it to the gauge. Now I can test most any vehicle with a cigarette lighter.
Tested it out on my YJ and my WJ. It works great. Next thing I need to do is figure out a simple suction cup mount to be able to put it on the windshield.

http://img.photobucket.com/albums/v606/JeepsAndGuns/20160302_173304_zpsaz161wuw.jpg