Have been gradually losing fuel  pressure, adjustment screw didn't help, so figured maybe filters needed changed. No difference! Tried to call pure flow, left some messages but no one called me back. I finally got ahold of someone yesterday, (no call back cause they were getting ready for big diesel event) anyway, he told me to check inlet screen and get serial #. I was a little concerned as I thought warranty was 1 year. Screen was clean so called back today. Dummy me, never sent in warranty card! They said "no problem"! Used serial # to find date of manufacture, and fortunately pump has 2 year warranty. They're sending me a new pump today! YeHa!

Hope this isn't a yearly occurrence!!

 

Raptor's with adjustable regulators have never been stable. The older design with the spring and check ball have always worked good. So yes it might be a yearly problem being the adjustable regulator design has always had an issue with holding good fuel pressure numbers. Also, the Raptor pumps have no return fuel line so they are more prone to cavitation issues and puts a lot a stress on the pump. Again like the full AirDog 100/150 pumps have the return line that keeps fuel flowing and reduces stress on the pump.  

I just installed a new RP150 with a fuel pressure fluctuation problem. I took out the screen during installation cause I wanted a pre lift pump filter. That way when clogs occur it can be changed.

 

I called the tech down there at PureFlow about the fluctuation problems and they were very nice, are sending a new pump. They want me to send back this one for testing and why it also squeeked at first starter bump.

 

My 02 has the RP 100 for a lot of years and pressure has to be adjusted up about every two years or so so no going below 14 psi problems.

 

Is it  a possible  better situation running all the return thru the VP for cooling? I wouldn't even pretend to know anything more than the site owner... just a question.

Edited April 21, 20178 yr by JAG1

My AD II has the pressure regulator. I have never had to mess with it after initial set up. The first one went 6 years with no adjustment and the second one I have never adjusted. It has lost about 1 psi but still sits at 15 and 18. Wonder if there is a difference between the two?

Just another series of issues with AD stuff. It's been a long time since they had a good reputation. 

 

 

Got new pump. No difference! Should have checked fuel pressure with a separate gauge to begin with. I thought I had 2 pounds but had 30 pounds. 

The isspro gauge I have came with an elbow that goes on the gauge, because of this I had a kink in the high quality plastic line that also comes with the gauge. Installed a straight compression fitting, re bled line, and backed pressure waaay down.

All is good again, hopefully. 

If vp44 seal leaks because of excessive fuel pressure, how will I tell?

Glad you got it figured out, chaulk another one up for the longevity of the old raptor 100. As far as damage to the vp, I've heard even though they don't need or like it, they can handle the high psi. as long as it wasn't for to long . 

Many companies are blamed for installer error. Glad you got it figured out.