All C4 Schrader valves the same?
Thread Starter
Drifting
Joined: May 2002
Posts: 1,509
Likes: 3
From: Hazel Park MI
All C4 Schrader valves the same?
I bought an Accell rail-mounted FP gauge from Jeg's. They had 2 diff. part #'s, one for 85-89 TPI, the other for 90-96. I get the part and the box says 86-96 :confused: Trusting Accell and Jeg's, I install it and it leaks where the fitting meets the stem toward the gauge, just above the Schrader valve :mad
I'm sending the part back, but I don't want the jokers to send me the same part and have the same thing happen.
So maybe some of us can compare Schrader valve measurements to see if there is a big diff. in dimensions between the years.
The measurements of my 85 4+3 are:
distance across top of valve - 6mm
distance from top of valve to end of threads - 15mm
distance from top of valve to fuel rail - 20mm
I called Accell, and they had no part listed for the 85 - just 86-96. They gave me the Accell tech line #, but that Mike joker hasn't returned either of my calls.
TIA to those, if any, that take the time to do this. :seeya :steering:
I'm sending the part back, but I don't want the jokers to send me the same part and have the same thing happen.
So maybe some of us can compare Schrader valve measurements to see if there is a big diff. in dimensions between the years.
The measurements of my 85 4+3 are:
distance across top of valve - 6mm
distance from top of valve to end of threads - 15mm
distance from top of valve to fuel rail - 20mm
I called Accell, and they had no part listed for the 85 - just 86-96. They gave me the Accell tech line #, but that Mike joker hasn't returned either of my calls.
TIA to those, if any, that take the time to do this. :seeya :steering:
Le Mans Master
Joined: Jan 2002
Posts: 5,320
Likes: 4
From: Kyle TX (Because Mojo Made me fill it in)
Re: All C4 Schrader valves the same? (jmrl98)
I went through the search of looking for the correct filling for a FP gauge not too long ago. The schrader valve is a male AN-4. Whatever goes on it will need to be a female AN-4. Your FP gauge fitting is most likely a 1/4" pipe connector so you will need to convert it from an AN-4 to 1/4" pipe. I went with something like this because it was cheaper than the $30 jobs from Summit.
Burning Brakes
Joined: Feb 2000
Posts: 871
Likes: 1
From: Westland MI.
Re: All C4 Schrader valves the same? (VetteNoob)
VetteNoob,
Is that your FP gauge right there, or is that an isolator to run your gauge in the cockpit? The only isolators that I can find right now are for carburated applications. AutoMeter was working on one for FI, but I'm not sure if it's out yet. If you have a part number, let me know.
The schrader is a #4 AN. The back of my indicator is also pipe thread, but it came with a pipe to AN union. I just used a short flexible aircraft line to mount my gauge on the firewall. You can also get some #4 B nuts and ferrules and make your own line out of aluminum or steel. The aircraft flare on AN hardware is 37*, but an automotive flare of 35* will work and not leak.
Is that your FP gauge right there, or is that an isolator to run your gauge in the cockpit? The only isolators that I can find right now are for carburated applications. AutoMeter was working on one for FI, but I'm not sure if it's out yet. If you have a part number, let me know.
The schrader is a #4 AN. The back of my indicator is also pipe thread, but it came with a pipe to AN union. I just used a short flexible aircraft line to mount my gauge on the firewall. You can also get some #4 B nuts and ferrules and make your own line out of aluminum or steel. The aircraft flare on AN hardware is 37*, but an automotive flare of 35* will work and not leak.
Le Mans Master
Joined: Mar 2001
Posts: 9,464
Likes: 1
From: Modesto CA
Re: All C4 Schrader valves the same? (VetteNoob)
Vettenoob,
Didn't I send the fittings with the guage? I paid $15 from a local speed shop for the fittings, and they looked exactly like the one you have now, except they were blue...
Nice fuel pressure guage though :D
Didn't I send the fittings with the guage? I paid $15 from a local speed shop for the fittings, and they looked exactly like the one you have now, except they were blue...
Nice fuel pressure guage though :D
Le Mans Master
Joined: Jan 2002
Posts: 5,320
Likes: 4
From: Kyle TX (Because Mojo Made me fill it in)
Re: All C4 Schrader valves the same? (TIMSPEED)
Tim, you did, but the ones you sent swiveled and developed a leak at the o-ring. I priced a fitting like the one you sent and they wanted $30 for one (shipped) so I decided to get one from a fitting shop in Houston. That thing you see cost like $11. I have an Aeroquip catalog for all my fitting needs. :D
Yeah, Id say that's one of the best $100 I spent. I should find more like the one I bought from you and get them exchanged by Autometer and sell them :lol: .
[Modified by VetteNoob, 11:46 AM 3/14/2003]
Yeah, Id say that's one of the best $100 I spent. I should find more like the one I bought from you and get them exchanged by Autometer and sell them :lol: .
[Modified by VetteNoob, 11:46 AM 3/14/2003]
Thread Starter
Drifting
Joined: May 2002
Posts: 1,509
Likes: 3
From: Hazel Park MI
Re: All C4 Schrader valves the same? (VetteNoob)
vettenoob, thanks for the response and pictures, but I can't open the pics here at work (filter). But let me see if I got this straight. I have to convert the fitting on the gauge, not attach a fitting on the valve? The fitting on the gauge won't come off the assembly, so I buy something to attach to it, then to the valve? :confused: Sorry for not following if I have it wrong! :seeya
Le Mans Master
Joined: Jan 2002
Posts: 5,320
Likes: 4
From: Kyle TX (Because Mojo Made me fill it in)
Re: All C4 Schrader valves the same? (jmrl98)
The fitting on the fuel rail does come off, but I found that the plenum gets in the way of anything I try to put there is I dont 90* it away from the rail. Im not certain what the fitting size is for the rail itself.
The fitting on the back of most FP gauges I have found were 1/4" pipe fittings and the schrader valve fitting is #4. This leaves you with having to find converters to turn your male 1/4" pipe into a female #4.
Essentially I think what you will need is:
female 1/4" pipe to female AN #4
Then all you have to do is determine if you need to angle it out away from the fuel rail to clear the plenum.
In my particular situation, I asked for a:
female 1/4" pipe to female AN #4 with a 90* elbow
Here are the part #s and where I got them:
GHX Inc
4360 Gessner
Houston TX 77041
713-939-7423
Part#s
2242-2-4S
2071-4-4S
The fitting on the back of most FP gauges I have found were 1/4" pipe fittings and the schrader valve fitting is #4. This leaves you with having to find converters to turn your male 1/4" pipe into a female #4.
Essentially I think what you will need is:
female 1/4" pipe to female AN #4
Then all you have to do is determine if you need to angle it out away from the fuel rail to clear the plenum.
In my particular situation, I asked for a:
female 1/4" pipe to female AN #4 with a 90* elbow
Here are the part #s and where I got them:
GHX Inc
4360 Gessner
Houston TX 77041
713-939-7423
Part#s
2242-2-4S
2071-4-4S
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