This morning I started my truck and I am sitting a very nice 18psi at idle and 15.5psi at WOT, nothing wrong here just normal everyday stuff. Temp outside is 68*F around 2pm

 

Just now I went to the corner store and I started my truck, mind you there is not hard start, and I noticed the fuel pressure is sitting at 12psi at idle and 10.5psi at WOT(for a very short run). Now the only conditions that have changed is the weather. It is currently 9:15pm outside and the temp is 30*F. Now I am hoping this is just because the temp difference is such a drastic change that the fuel is thicker? I also have a little less than a 1/4 tank in the truck. 

 

Is my fuel pressure this low because of the drop in temp outside or do I need to look into something else?

Well I don't mind where the needle valve goes. I just need to know how to adapt it to what I have now. So I either remove the hose from the main fuel supply or I remove it from the isolator. Either one poses an issue on just "sticking" the needle valve there. I would honestly like to tap the line where it meets the isolator so what way I don't have to buy more tubing for cutting and splicing. 

So you need a barb fitting on one side of the needle valve and a compression fitting on the other side. Somthing like this:

 

http://www.sustainablesupply.com/Weatherhead-A660-Needle-Valve-Straightway-1-8-In-p/w191459.htm

 

And:

 

http://www.oreillyauto.com/site/c/detail/EDE0/744620.oap?partType=N1166&parentPartType=C0075

 

Then you would just need a 1/8" union to tie them together. I think the number for that would be:

 

http://www.oreillyauto.com/site/c/detail/EDE0/203200/N1165.oap?ck=Search_N1165_1106176_-1&pt=N1165&ppt=C0248

Since we are on this topic, I have a problem as well. I am experiencing the exact same symptoms as Kotta is actually. The only difference is the ambient air temp this morning for me was about -12* F. I know for a fact that I my fuel is blended for -30* so I dont think it could be gelling. After letting the truck warm for about 5 minutes this morning I took off for work with about 20psi at idle. By the time I got to work it was idling at about 4 psi It didnt fluctuate at all it just very slowly dropped over time. I didnt try opening the needle valve more or anything like I should have. This is with my  raptor 100. Could the pump just be too cold or something?

The oreilly links didn't work. I am assuming you are suggesting that use the current hose that is tapped from the main supply line?

Yes. Google these part numbers:

 

Edelmann 744620

Edelmann 203200

Just so I get this straight. The second part will be the union for the fuel hose coming out of the main supply to connect to the needle valve? The first part will screw into the other side of the needle valve leaving just a push on hose fitting? Sorry for the questions, just trying to understand.

 

Oh and just so there is no confusion. I am not trying to remove the hose at all that is coming from the main fuel supply line, just trying to adapt from there to the gauge. 

Edited December 30, 201311 yr by Kotta390

NAPA - WH6820 approximately $8 to $10 bucks for the needle valve. The tubing is Air Brake line rated for 600-800 PSI burst strength I doubt it will burst and leak in the cab.

 

Question why is it that every panics about a fuel pressure gauge be isolated but doesn't think anything about running engine oil pressure into the cab with over 80 PSI in the tube?

 

 

Just so I get this straight. The second part will be the union for the fuel hose coming out of the main supply to connect to the needle valve? The first part will screw into the other side of the needle valve leaving just a push on hose fitting? Sorry for the questions, just trying to understand.Oh and just so there is no confusion. I am not trying to remove the hose at all that is coming from the main fuel supply line, just trying to adapt from there to the gauge.

Yep. With those three part numbers I have you, you will be able to just pull out the isolator and adapt the rubber hose to the plastic fuel line with the needle valve in the middle.

NAPA - WH6820 approximately $8 to $10 bucks for the needle valve. The tubing is Air Brake line rated for 600-800 PSI burst strength I doubt it will burst and leak in the cab.

Question why is it that every panics about a fuel pressure gauge be isolated but doesn't think anything about running engine oil pressure into the cab with over 80 PSI in the tube?

Haha as soon as I learned about using a needle valve on the FP gauge I put one in for my mechanical oil pressure gauge. Like you said its very funny how most people don't even bother with it.

Well I am finding it hard to find a 1/8" compression fitting on one side of a needle valve and maybe a 5/16" inlet side. Anyone come up with this style of needle valve I need? I really don't want to rip apart the a-pillar again cause I have done it 5-6x already and the damn thing is getting harder and harder to put back together.

What about this to replace the isolator?

 

http://www.vulcanperformance.com/Fuel-Pressure-Snubber-p/snbr.htm

Or I could take the fittings out of the isolator and put this inline with it since it will adapt to the hose and the compression fitting at the same time.

 

 

http://www.ebay.com/itm/1-4-NPT-Brass-Needle-Valve-NEW-/390656308334

What about this to replace the isolator?

 

http://www.vulcanperformance.com/Fuel-Pressure-Snubber-p/snbr.htm

 

I'm not sure. I've heard mixed reports of snubbers some work and some don't. If you do opt fo the snubber I would still highly suggest you add a needle before the whole system so to turn it off in case of a problem.

I'm not sure. I've heard mixed reports of snubbers some work and some don't. If you do opt fo the snubber I would still highly suggest you add a needle before the whole system so to turn it off in case of a problem.

 

 

I do like the idea of the valve to shut off the supply. I think I will skip snubber all together. Now I need to just buy a 1/4 npt needle valve straight through. I completely forgot that the fittings on the isolator are 1/4 npt and I can just remove those and put them in the new needle valve.

 

This is basically what I need but there has to be a cheaper solution to this than $60!

http://www.sustainablesupply.com/Parker-4F-V6LN-B-GR-Needle-Valve-1-4-In-Brass-F-p/w171164.htm

Edited January 2, 201411 yr by Kotta390

Vulcan has the needle valve you need.http://www.vulcanperformance.com/Brass-Needle-Valve-p/bnv.htm. Some folks get them at NAPA, but I got mine form Vulcan with some other things.

Vulcan has the needle valve you need.http://www.vulcanperformance.com/Brass-Needle-Valve-p/bnv.htm. Some folks get them at NAPA, but I got mine form Vulcan with some other things.

 

I actually need a double 1/4 NPT female Needle valve

Go to an ACE's Hardware. I got a needle valve out of their plumbing section for mine. I'm sure other hardware stores will have it if you don't have an ACE's in your area...

Go to an ACE's Hardware. I got a needle valve out of their plumbing section for mine. I'm sure other hardware stores will have it if you don't have an ACE's in your area...

 

 

That's where I was thinking about going. I have one a half mile from the house. It's either that or Lowes. Someone has to have it lol.

I actually need a double 1/4 NPT female Needle valve

 

I guess I should have read the previous post a little better. The 1/4" are easier to find locally.

I do like the idea of the valve to shut off the supply. I think I will skip snubber all together. Now I need to just buy a 1/4 npt needle valve straight through. I completely forgot that the fittings on the isolator are 1/4 npt and I can just remove those and put them in the new needle valve.

 

This is basically what I need but there has to be a cheaper solution to this than $60!

http://www.sustainablesupply.com/Parker-4F-V6LN-B-GR-Needle-Valve-1-4-In-Brass-F-p/w171164.htm