jlb586

OK ok ok....So I picked up a fuel rail and old stock injectors from the JY.

I scored some new O-rings from AZ (FelPro ES70599).

Now upon looking closely, I THINK these are two different o-rings.

--FULL VIEW--



--STOCK BROWN ONES--


These look IDENTICAL...

--STOCK BLACK ONES--


These DO NOT appear to be the SAME??

These aren't upgrades, just simply some freshly cleaned stock injectors (#53030778)

Where do I get the fatter stock black ones?? Or do I not need to replace them? The fat black ones are the rail side.

thanks
-jb

Radi

Same o-ring on the rail side as on the intake side. The rail side looks a bit fatter and flatter after a while since they're fit in there tighter. The rail side has to hold back 50-60# fuel pressure all the time, while the intake side is just sealing vacuum.

DFlintstone

Yep. They can look flat, worn. Just be careful to work them in even without pinching one. (like I did once on the engine side. I'm pretty strong and found it a bit tough getting them in the head with them in the rail. Awkward leverage. Then another time it was easy. Anyway ATF is what I had handy, I'm not sure what might be better.

CrawdadSlim

The haynes repair manual states that the o rings on the intake side and the rail side are not interchangable. I usually **** can what the manual says. I trust quality aftermarket over oem. I used new 10w30 to lube my o rings. No leaks.

salad

All that effort for stock injectors?

Anyways yes they look different because the old ones have been mashed in place for a decade.

CrawdadSlim

Anyways yes they look different because the old ones have been mashed in place for a decade.[/QUOTE]
Just in case someone bought an oem set of o rings here is a quote from the haynes repair manual:" An o-ring kit is available from a dealer parts department. This kit consists of 6 brown and 7 black seals. The brown seals fit on the injector tips; the black seals fit on the rail end of the injectors. Do not switch the brown and black o-rings-they're different in design and composition. The extra black seal is for the fuel pressure regulator." Hope this helps.

salad

Interesting. My Ford injectors had blue and green rings, rebuild NAPA Echelin kits for both the Ford and Jeep specs had two identical black O-rings.

CrawdadSlim

yeah, it is an interesting subject. The o rings I pulled from my 2000 looked identical. Maybe its a pre 99 thing.

DFlintstone

I confess..It's a bit of bumpy gravel for me to even get to asfault, then a ways to town from there. If I don't see cracks under high magnification, I'm using them. I'm not suggesting anyone else does that, but I do, on my own Jeep.

Under good light with high magnification, If I can bend it and see no cracks, I might just run that.

Kalali

Mine (2000 XJ) looked the same on both ends when I replaced them last year. The replacement parts from NAPA were also identical. I can understand why they could be different since their applications are different - exposure to heat, pressure, etc., but it looks like they made them the same for 2000+ MY.

salad

With the NAPA ones I assumed that they made both to the higher spec. Easier to stock, less user error, etc.

CrawdadSlim

Bravo.

jlb586

Oh,I haven't gotten any notifications of updates to this post.

I though wrong.

But..they are the same? I guess that makes sense when you consider their applications.

Well, I guess I can give this a run this weekend.

It's a 1998 XJ.

I'll keep ya'll posted!

thanks.
-jb

CrawdadSlim

As long as you trust Felpro and your sales rep you are probably safe. Legit aftermarket companies don't reproduce parts and components they don't need to.

jlb586

Well,

I haven't a clue. I've heard so many different stances on this question.

They are the same, NO, they are different. MAYBE they are the same, but they MIGHT be different.

Obvs, they look different, and they are different colors. When I looks on RockAuto for RAIL side o-rings...they are brown, but stock, the INJECTOR side is brown??

My last ditch effoert it to go in to NAPA and give them my injector with the 2 o-rings and see if they can find a match for both.

The FELPROs look like the stock brown ones, no clue about the fat black stock ones on the rail side...?

I'm not even sure if the dealership would stock these, heck..I don't even know if there's a JEEP dealer around here.

thanks
-jb