My $25 Fuel Pump Check Valve Fix

I got the valve off ebay for $16. 18" of fuel inj. hose for $8 at the parts store. The clamps I had. I installed this just after the filter. Ignition on, engine off, pressure went to 55 psi. Ignition off pressure dropped to 50 psi after about 10 min. After 30 min the pressure still reads 50 psi. I couldn't resist waiting any longer so I took the gage off and the truck started right up with no problems. It's been a few days since I did this mod. and it starts up like it used to. So there you have it. Cheap and simple.
http://i28.photobucket.com/albums/c201/camaro396/Other/CheckValveInline.jpg
http://i28.photobucket.com/albums/c201/camaro396/Other/CheckValve-1.jpg

your relay must be bad-- FP is running off the oil pressure switch only---- why not just fix what is broke?

I disagree, I think his relay is just fine. My fuel pump runs for a min with the engine offwhen I turn on the key. OP, thank you for posting this as I just replaced my fp because of the check valve issue. Next time I will fix it myself like you said.
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your relay must be bad-- FP is running off the oil pressure switch only---- why not just fix what is broke?

Huh? How can the oil pressure switch turn on the pump before the engine starts?

If the relay is bad the pump would not work at all. Ignition on gives the signal to the timer, timer to the relay, the relay then gives the signal to the pump. Timer times out, relay opens, pump stops. What ever pressure builds in that time frame the check valve holds it untill engine starts and then the pump runs constant. BINGO

Huh? How can the oil pressure switch turn on the pump before the engine starts?

If the relay is bad the pump would not work at all. Ignition on gives the signal to the timer, timer to the relay, the relay then gives the signal to the pump. Timer times out, relay opens, pump stops. What ever pressure builds in that time frame the check valve holds it untill engine starts and then the pump runs constant. BINGO

But if the check valve was a good fix the pressure should be over 60 psi key one engine off, a weak fuel pressure regulator could allow a little pressure to escape.

The oil pressure switch can't turn the pump on before the engine is turned over, it can while the starter is running, it doesn't take much oil pressure for the oil pressure switch to power the fuel pump.

If the relay is bad the oil pressure switch can power the fuel pump, but it would not run for the usual two seconds after the ignition is turned on

But if the check valve was a good fix the pressure should be over 60 psi key one engine off

In the perfect world it would be. That is assuming the pump can put out 60 + psi the pressure and the regulator is accurate.

My truck runs fine at 55 psi.

My Astro van was starting hard- took 4 to 8 seconds of cranking for it to start- then I jumpered the FP primer lead once and it started on first crank-- so I checked the relay- and it had a melted spot in the relay connector-- where it had been arcing- and wasn't always energizing the FP. The fuel pump can be switched on by only 4 psi oil pressure-- the starter will generate that after about 4 or 5 seconds of cranking---so it can be a bad relay or relay socket-- I replace both the relay and the relay socket and never have long crank times again.

The fuel pump can be switched on by only 4 psi oil pressure-- the starter will generate that after about 4 or 5 seconds of cranking---so it can be a bad relay or relay socket-- I replace both the relay and the relay socket and never have long crank times again.

Maybe you should reread my original post. I'm talking about holding fuel pressure before the starter hits a lick and before oil pressure builds and closes it's contacts. My situation is before that.

I got the valve off ebay for $16. 18" of fuel inj. hose for $8 at the parts store. The clamps I had. I installed this just after the filter. Ignition on, engine off, pressure went to 55 psi. Ignition off pressure dropped to 50 psi after about 10 min. After 30 min the pressure still reads 50 psi. I couldn't resist waiting any longer so I took the gage off and the truck started right up with no problems. It's been a few days since I did this mod. and it starts up like it used to. So there you have it. Cheap and simple.
http://i28.photobucket.com/albums/c201/camaro396/Other/CheckValveInline.jpg
http://i28.photobucket.com/albums/c201/camaro396/Other/CheckValve-1.jpg

Do you have the link to the ad or the seller ID. I'd like to try this out for my Blazer.

Here is the seller id jbass195

►►UPDATE◄◄ After 1 1/2 months the valve has failed to hold pressure. Well actually it will hold 10 psi but not nearly enough for a quick start up. I did some research and bought one from McMaster Carr.

does this connect to the fuel filter fittings/fuel line to engine with out adapters? it looks like a better design ..

I would hook this check valve up to the input of the fuel filter. that way the fuel filter having a larger supply of fuel held at the 53-60 psi pump pressue.....

I went with 1/4 NPT and barb fittings. So far so good.
They have other sizes also..
Female x Female
1/8" X 1 3/8" OAL
1/4" X 1 51/64" OAL
3/8" X 2 1/4" OAL
1/2" X 2 35/64" OAL

I went with 1/4 NPT and barb fittings. So far so good.
They have other sizes also..
Female x Female
1/8" X 1 3/8" OAL
1/4" X 1 51/64" OAL
3/8" X 2 1/4" OAL
1/2" X 2 35/64" OAL

did you measure pressures ? try upstream [input] of fuel filter ?

The oem regulator is in the fuel rail. Its a $30 part and takes less than five minutes to replace. The modifcation serves the same purpose, but the OEM regulator is also very easy to replace and inexpensive.

http://www.saltedwound.com/wp-content/uploads/2008/08/dscn5173.jpg

the fuel pump has a check valve. his pressure dropped off rapidly..rather than replacing the fuel pump he installed an external check valve. this then kept the pressure from droping at the fuel rail test valve..

the fuel regulator on the driver side fuel rail is modulated by the vacuum ..with no vacuum maximum pressure, with high vacuum lower pressure...pressure range is 53psi to 62psi...this regulator is no check valve. however if this regulator diaphram has a hole in it it will cause rapid fuel pressure drop off as well as engine runing issues[fuel sucked into the intake]

low vacuum would be WOT acceleration, obviously you want the high fuel pressures...at idle [high vacuum] this would the produce lower fuel pressures..

I was hoping he responded with more about the check valve he used..this could help out some with this issue with a quick fix until the fuel pump could be replaced..