Fuel Pressure Regulator malfunction and repair

Over time I've been having problems with what I thought was a fuel pump issue, subsequent to removing, overhauling and reinstalling the fuel pump on my '98 Riv. I had bought a new CarQuest closeout pump (an Airtex) and was going to install it after overhauling the OE fuel pump and noticing that the car was having a problem with long starts and minor problems on very hard acceleration.

Ha!

Problem was, 'long starts.'  Workaround was to turn the key on and wait until the FP stopped, then start the car.

I figured the pump was failing,  BUT I pulled the fuel pressure regulator first. It's a Standard, I had it on hand and put it on a couple years ago when I overhauled the throttle body.  

Good thing.

It was full of trapped fuel.  It weighed several times the replacement. I was all set to replace the fuel pump. Very glad I swapped the FPR out first.  Didn't have to touch the fuel pump.  Which I should have figured out.  If the FP was the problem, I would have had more issues than long starts.  


With the FPR replaced, the long starts are fixed.  

What I think I learned was if I have long starts, get a cheapie FPR (junkyard OE pull will do) then remove the one on the car, drain the gas out of it then compare weight of the new one to the old one.  If the old one is still a lot heavier, replace it with the cheapie.  At my leisure then I can replace the cheapie with a new Delco, Delphi or Bosch.

I'm about to replace my FPR with an ACDelco unit from Rockauto. For a few days it has struggled to start, but after a couple tries it does. Also I pulled the vacuum line to it and it leaked out fuel, so I know it's bad.
But how do you change it? Do you just pull it off? Any tips are appreciated.

intosilence1 wrote:

I'm about to replace my FPR with an ACDelco unit from Rockauto. For a few days it has struggled to start, but after a couple tries it does. Also I pulled the vacuum line to it and it leaked out fuel, so I know it's bad.
But how do you change it? Do you just pull it off? Any tips are appreciated.

According to my FSM, the FPR sits inside a housing.  There is a snap ring that needs to be removed and a screen.  Looks pretty simple once you remove the snap ring.

Probably similar,

https://www.youtube.com/watch?v=VmYsUjk0KDY&ab_channel=KingQuadRules

LARRY70GS wrote:

intosilence1 wrote:

I'm about to replace my FPR with an ACDelco unit from Rockauto. For a few days it has struggled to start, but after a couple tries it does. Also I pulled the vacuum line to it and it leaked out fuel, so I know it's bad.
But how do you change it? Do you just pull it off? Any tips are appreciated.

According to my FSM, the FPR sits inside a housing.  There is a snap ring that needs to be removed and a screen.  Looks pretty simple once you remove the snap ring.

Probably similar,

https://www.youtube.com/watch?v=VmYsUjk0KDY&ab_channel=KingQuadRules

This is correct.  If you look very closely at the FPR you'll se the snap ring, and the little holes where the pins of the snap ring pliers fit.  If you don't have a set of snap ring pliers, go get one.  For a DIY-er the $6.00 "Shopworks" set from your local NAPA will work fine.  I got mine from Sears I forget how long ago.  I have not had to use them even once a year but they are definitely worth it.  


Before you remove it, get a (fairly large) rag and use it to cover the Schrader valve while you relieve the fuel rail pressure.  If you have a better way, do that instead of the rag-and-drift thing.  After pressure is relieved, then check the direction of the nipple (so you install the new one same orientation) then remove the snap ring.  Once you have removed the snap ring, the unit simply pulls out of the mount.  You do have to pull kinda hard.  Be sure none of the o-ring is left in the mount on the fuel rail.

Installation simply presses into place. You will have to press pretty hard to get the FPR seated such that the snap ring can be reinstalled.

If you're going to continue DIYing stuff like this, great, but Get The Fine Factory Service Manual - you will very much need it and you can usually get a set for $50 or less, used, via eBay or other listing sites.

Identify and locate the fuel pressure regulator within the fuel system of propeller airplanes. I'd also oversee the paplication of fuel tank sealants such as pr1440b2. Needless to say, it's a long but imperative process.