O-rings leaking fuel? Broken Plastic parts in fuel system? Interesting Info
 

In light of a several recurring fuel problems I have had with my 2003 XKR, I have done a lot of research about recent fuel blends and have continued to keep my eye open for information about this subject.

Here's an interesting article I found a few days ago on Hot Rod Magazine's website that is good news for those of us that have had problems:

http://tinyurl.com/a8mwf8k

Additionally, my local chapter of JCNA, the Heart of America Jaguar Club - serving the Kansas City Area has asked me to write a tech column for our newsletter.
Here is an excerpt from a recent article that I have written that may contain information that others on this forum would benefit from. It is regarding fuel pressure damper O-rings I found leaking twice in the same year on my car.

From "The Jagwire" - HOAJC Newsletter:

*************************

For review, fuel pulsation dampers are used on many modern fuel
injected engines. Jaguar uses them to lessen “standing pressure waves”
within fuel rails. This reduces injector open and closing
pressure-pulse induced clicking noises and smoothes the fuel flow in
our high performing cars. This is “all good” when they are sealed up
and not dangerously leaking gasoline onto the very hot cylinder heads –
but when they do leak, the situation is at least a smelly annoyance and
at worst, a severe risk for an engine fire.

***************

The Jaguar recommended procedure for this leaky situation is to replace
the entire stainless steel fuel rail assembly with the dampers
pre-installed by OEM means. Last spring, when the first leak was
detected, the Jaguar dealership here in the Kansas City area quoted me
approx $3100 for the complete repair. That number convinced me that
this would be a job attempted at home!

Unfortunately, I found out a new “Jaguar parts department sourced” fuel
rail is north of $1,400… Whew! For most of us driving and enjoying our
older vehicles that’s a bit pricey. And if indeed that rail was from
NOS parts stock, the O-rings were likely to be original… In other
words, made of a non-alcohol blended fuel resistant material likely to
begin leaking again in the near future.

This brings me to an important part of this discussion:

The O-rings originally installed by Jaguar, and the replacement rings
that the Houston fuel injector service company installed, were both
made of DuPont “Viton flouroelastomer GLT” rings - blue in color. After
days research on the “how and why” of fuel dampers, O-rings, and the
material the rings were made of, I discovered that the high performance
GLT grade rings are not recommended by DuPont for use with automotive
fuels oxygenated or blended with MEOH and ETOH alcohols or MTBE
antiknock agents. Unfortunately, this is exactly the kind of fuel (in
the higher octane blends recommended for our Jaguars) available today
at most Midwest USA gas stations!

For the record, research led me to a newer “rubber” called GFLT.
O-rings made of this material are more resistant to the degradation
caused by the corrosive qualities of alcohol in today’s fuel, according
to DuPont.

I don’t know when (or if) Jaguar eventually began using GFLT or another
new brand or grade of O-rings in our cars – as the bio-fuel boondoggle
did not start hitting Europe until around 2010. But I’d hope that the
Coventry engineers eventually discovered and rectified the problem. It
is worth mentioning at this point, that many of the plastic parts in
our beloved Jaguar fuel systems are also being quickly degraded by the
fuel blends containing alcohol. Just take a look at the various Jaguar forums
to see the sudden spike of expensive fuel pump problems that are
stalling our cars in unprecedented numbers.

Please do yourself a favor and, while it is still available, do your
best to purchase fuel that is not blended with alcohol. Not so easy to
find this fuel, I know - but here’s a link that may help:
Ethanol-free gas stations in the U.S. and Canada

*********************************

Now, back to my specific situation: Since it had been only a few miles
since the damper O-rings had been replaced (with Jaguar specified Viton
GLT rings) and the leak had returned, I had a big choice to make. I
could find a source for the exact size replacement O-rings in the new
GFLT formula “rubber” or do-away with those pesky dampers… I decided
not to risk a third engine teardown and chose to eliminate my dampers
entirely.

***********************

Take a look at some of my other posts and you will find more information as to the specifics of damper replacement.

I hope that my Jaguar Forums brothers and sisters find this research helpful!

Cheers!

Thanks for that Maxwdg,

This is ideal to let people consider if they may have this problem and the options.
Anyone that needs the details can have an evening reading your other threads!

I just finished pulling my fuel rails off the intake manifold, and luckily, I didn't separate the rail from the injectors (ok, I did one just to see this 'blue' o-ring). I reinstalled it, replaced the black ones on the intake side (OEM o-rings), then put it all back together. It ran tonight for about 10 minutes while I looked for air leaks and monitored the fuel trims. Thankfully, my injector curiosity didn't cause me a leak from pulling the blue side out of the rail (whew!!)

Guess this pretty much puts to rest the claims of those who have insisted that ethanol is perfectly harmless to fuel system components.

I appreciate this thread very much. As many may have read here, I have been battling fuel pump check valve issues since April 2012. I won't go into the details here, but you can read the thread if you want to. Since my most recent (6th) pump replacement I have used only ethanol free fuel and this pump has lasted longer than any installed sans the original pump. There is a lot of information on the web about ethanol blended fuel, here is one site which I feel has a lot of good information Well-Worth Products, Inc.: Articles - White Paper on Emergency Backup Power Generators and Fire Pumps
and as with most things on the Internet there is no definitive answer on the subject, but some things are factual such as ethanol absorbing water, deteriorating certain rubber and plastics, being an excellent solvent, and forming a gummy film on components. How MUCH these things are a problem is really what is in question, and I think there are a lot of factors involved that can affect how problematic these can be. One facotor I believe in play for me is that I live in Florida, a high humidity climate, and I don't use the car all that much so with my car sitting my fuel may go stale in the tank and be more susceptible to problems. Also, the actual percentage of ethanol is not supposed to be greater than 10% but this seems to be an unregulated area and many sources inicate blends much higher which can make the problems worse. As I said, I have been using ethanol free fuel since the last pump and this has lasted the longest of all replacements and I believe this is why. If more of us use ethanol free fuel, and the demand increases, then maybe that will help ensure these stations don't stop selling it, and maybe more stations will start carrying it. Additives coming onto the market to counter these ethanol related problems is also an interesting subject, but I am skeptical, more information is needed on these, and it is a fairly new market so I think it will take time. Thank you again for bringing up this topic.

Man SteveJacks, I have read your thread about you fuel pump woes. Every time I read about ANOTHER pump having to be put in your tank, I feel for you.

In addition to the O-ring leaks I've had in the last year, I had to replace my fuel pump about a year and a half ago. In my case, it was the motor that had shot craps - but I did find that I had a very limited amount of time before another one of the white plastic parts on top of the swirl-pot in my tank broke off, which would have stopped the flow of fuel to the line. I found two tiny plastic tabs that had already broken off (from chemically fatigued plastic) in the bottom of my tank. I was lucky to have found a used pump from a breaker yard in CA. I don't know how long it will last.

Thank YOU for the additional link!

Is the fuel pump in the 2003 model cars different that the pump in the earlier cars, 96-2002? That is do the pumps in the earlier cars not use the plastic that is failing due to the alcohol? Right now there is a lot of talk about increasing the amount of alcohol to 15 percent. And with the current administration in the USA I think that will happen. And alcohol free fuel is very difficult to find in a lot of areas.

The 4.2 cars have a returnless fuel system and a completely different pump configuration. The problems seem to come in that the check valves and pressure relief components are part of a single plastic assembly that lives in the tank. Not only is it a PITA to get to but it is also absurdly expensive.

I doubt the earlier cars are immune to the problems but they generally are less costly to fix.

The 15% alcohol mix is likely bad news for older vehicles and there have been a number of consumer groups campaigning against it, including AAA.

AZ has limited sources for alcohol free fuel so I'm glad to see threads like this so I know what replacement parts to look for if (when?) the time comes.

Rev Sam had posted sort of recently that he had a newly revised idea about an external check valve but needs someone with a current check valve problem to see if it works. While the check valve isn't the only issue suspected to be related to ethanol, it does seem to be a more common issue. Maybe he has more input?

Now on the 3rd pump, I still have a minor check valve problem (long crank) that shows up somewhat inconsistently, usually after a good long run where the engine compartment is full heat soaked.

I have started to put together a check valve with a pressure relief to replicate the function that is in the tank as part of that assembly. I was wanting to make it so that it utilized the quick connect for the fuel filter so that it was easy to remove should it not work.

Attachment 30427

The valves are 3/8, which is easy to come by, but the quick connect is a 5/16 tube, which is something I didn't figure out until I had pulled the connector off the fuel filter.

I need to change out the end fittings to accommodate it the smaller tube but 5/16 is a sort of odd size and isn't readily available at the local hardware store.

In the cooler weather the long crank happens less often so it hasn't been on my urgent list, but I think this will work. The prototype is a little clunky but could be made a lot smaller with machined parts and welding of the tubing instead of the fittings.

Very interesting work, guys. Much appreciated by those of us here who are concerned about the quality (or lack thereof) of our fuel pumps....

It appears to me that the XKs used as daily drivers may stand a better chance of avoiding fuel pump failures regardless of ethanol content in the available local fuel. My wife's XK8 is a daily driver, so perhaps I'll get lucky in this instance....