Need fuel pressure regulator brand advice - 87 4.0

[87MJJeep]

I changed out my fuel pressure regulator this weekend with a Standard Ignition brand PR21.  It is what O Reilly’s and Amazon sell.  There were a few bad reviews on Amazon, but so many more were positive that I tried it.  One reviewer posted a video showing a fine line of fuel spraying out of the side of the body.  Ultimately, I had a similar occurrence, but only saw it three times out of well over 2 dozen Key ON primes.  And my spray line was so fine, it looked as thin as a strand of hair.  What was consistent is a leak at the connection to the fuel rail.  Within seconds of priming, it's dripping.  

 

What is perplexing is the fact that upon installation, it seemed to be OK for a little while.  I drove it quite a bit Saturday and all was well, but Sunday I could smell some fumes in my garage, so I Keyed ON and from that point on, I got a leak every time.  Thankfully, it didn’t leak when I had last driven it.

 

I put the original regulator back on, but first I compared the two.  The diameter of the groove that the O-ring rests in was 8.48 to 8.51 mm on the original, and it was as low as 8.41 on the Standard PR21.  Also, the width of the groove on the OEM part was just wide enough for one O-ring to fit in the groove.  The Standard PR21 groove width is wide enough to fit maybe another 1/3 of the O-ring’s thickness.  So, I am curious what contributed to the leak at the fuel rail.  Is it the slightly smaller diameter mating to the inside diameter of the O-ring, or once pushed into the fuel rail, is the O-ring cocked at a slight angle due to the width of that groove? 

 

The Standard is made in China.  It was ~$50 on Amazon, and sells for ~$84 at O’Reilly’s.  (not to be confused with Standard “economy” model, PR21T.  It’s $37 on Amazon.) 

 

There is a Wells brand at Advance Auto, limited lifetime warranty.  The one photo doesn’t let me see how wide the O-ring groove is, but the shape of the casting where the vacuum fitting sticks out tells me it is not the same part as Standard.  Similarly, there is a GP Sorensen model at Autozone (3 yr warranty) for $85 that is different in appearance from both the Standard and the Wells.  I can even see “MADE IN USA” on the GP Sorensen.  It’s also hard to tell the groove width in its photos. 

 

I know most people shy away from Autozone parts, but the Made in USA has me considering it.  I’m curious if anyone has any experience with the GP Sorensen or Wells parts.  If not, my next step is to go to each store with calipers in hand and ask if I can look and measure the parts before purchase. 

 

I know NAPA is popular here.  NAPA carries Echlin, but the body/casing and stamped # on the part in their photos looks exactly like the Standard PR21.  Even the photo NAPA includes for instructions is exactly the same as what came with the Standard part. 

 

The second photo is of the Standard PR21 that I grabbed off Rock Auto.  You can see the how much the O-ring can move in the groove in that photo.

[87MJJeep]

I ended up getting the GP Sorensen FPR at Autozone for $86.  3 yr warranty and 2 miles from home. 

 

I would have gotten the Wells (lifetime warranty) at Advance with the 15% off code, but the closest one to me turned out to not exist.  They cancelled my online order after I got the "your order is ready" email.  The 2nd closest was 30 minutes away.  When I told the guy I was ordering it and would come get it, he pulled it from inventory (in their computer).  My shopping cart *instantly* went red where that part was now unavailable.  I asked if he just "pulled it" and he confirmed he had.  I told him I couldn't order it.  He put it back into the system.  I waited two hours, and it still was not available.  I wasn't driving an hour round trip to pay full price (he said they couldnt honor the online discount for walk-in customers).  And today, nearly 24 hrs later it's not appearing as available.   

 

It's always a drama working on cars...  

[DirtyComanche]

The o-ring groove probably is spec'd wrong enough to not work part of the time.  If they put a plastic/teflon backup ring in there as well then it would be fine, I bet.

 

You might have got away with it by just swelling the o-ring in some diesel/kerosene/naptha first, then installing it with vaseline.

[87MJJeep]

12 hours ago, DirtyComanche said:

The o-ring groove probably is spec'd wrong enough to not work part of the time.  If they put a plastic/teflon backup ring in there as well then it would be fine, I bet.

 

You might have got away with it by just swelling the o-ring in some diesel/kerosene/naptha first, then installing it with vaseline.

The GP Sorensen part's groove width was slightly narrower than the Standard part.  It definitely kept the O-ring more perpendicular to the axis.  I did use silicone lube on each O-ring.  Never would of thought of trying to swell an O-ring.  Good to know!  

[Htchevyii]

I used a Delphi FP10504 because it was the only one that I could find that wasn't made in China. I think it was made in Mexico.

[87MJJeep]

16 hours ago, Htchevyii said:

I used a Delphi FP10504 because it was the only one that I could find that wasn't made in China. I think it was made in Mexico.

 

That's a nice cross-reference!  I wouldn't expect a part on a RENIX system to be the same as a GM unit.  But I am not surprised.  

[DirtyComanche]

2 hours ago, 87MJJeep said:

 

That's a nice cross-reference!  I wouldn't expect a part on a RENIX system to be the same as a GM unit.  But I am not surprised.  

Lots of the Renix stuff is GM, some of it has been slightly modified (pins swapped, slightly different size, different threads, etc).