I have a chronic rust problem I am sure the rust is originating in the gas tank but how does it get past the fuel filter. I also see rust deposits around the inside of the fuel rail fittings and when I draw fuel at the rail it has a slight rusty brown color.
How is it possible that the rust is so fine it will pass through the filter and then coagulate in the rail when sitting?
Any one with this particular problem? Sure would like to hear from you.

 

I reckon the rust you're seeing didn't come from the tank but formed in the pipes and fuel rail themselves.

<shrug>

Just a thought.

Cheers
DD

 

that red stuff isnt rust. its some nasty red crap that occurs when gasoline evaporates or seperates into its basic components and it builds up in the bottom of your tank. try cleaning out your (slosh?) tank, its the smaller one and it has most of the nasty stuff in it.

there was a thread on here a while back where a member cleaned his out and he showed all sorts of crap. i suggest you read it. ill post a link if i can find it.

 

It is certainly worth cleaing out the swirl tank that sits under the battery in the boot.

I have also removed the fuel filter from the boot and relocated it to under the bonet so any debris in the fuel lines is filtered before it gets to the rail. It also means I do not spil fuel in the boot when I replace the filter.

 

Interesting, what your saying is the most logical explanation Iv'e heard. Rust would not go into solution with the gas when stirred and then come out when left to stand. I pumped all of the gas out of the tank using the cars fuel pump. Any type of filter configuration will not help here because the components go back in to solution with the gas. I am going to have to keep pumping clean gas through the system until it comes clean. good call M90

 

Pumping fuel through will not completely clean out the swirl tank as the pickup is not on the bottom of the tank and it has a strainer. The only way to get all of the debris out is to remove the swirl tank. This is not a difficult job, you should be able to complete it in less than a day.

 

I used to answer questions for generic XJS but there are generations of cars!

1975 to 1996???????????????????

Certain cars have certain faults.

TSBs for fuel problems?????

good luck!!!!!!!!!

bob gauff

 

oops...The cat is an 89 w/64k miles.

 

run a couple tank fulls of E85 that will clean it out.

have extra fuel filters avalible!!

 

What is the purpose of the swirl tank? I would rather eliminate it if it is nothing more than a weak link

 

Do you concur with M90's diagnosis that my gas has broken down and components of which have dropped out of solution?
I can't run anything through the tank until I get it clean enough so that I can start the engine without clogging the injectors. I've had the rail off twice and the injectors were packed solid both times.
I pushed the gas out of the tank with the fuel filter and amazingly, the first five gallons came out clean an clear, while, the second five were increasingly red with some mush floating around.
I am going to run another five through the system today, one at a time shaking the car in the process.
How should the swirl tank be affected by this process and what does e85 do to gas.
Thanks for the reply

 

The fuel tank is wide and flat bottomed. The purpose of the 'swirl tank' (really a relatively small and upright collection point) is to ensure that as long as there is some, however little, fuel in the main tank, there will always be a "sump" containing enough fuel to run the fuel pump without it running dry and failing, and the injectors running out of pressure on low fuel. This system work very well. I have (inadvertently, while calibrating a new fuel sender) run my car down to NO visible fuel in the main tank and it still ran perfectly.

The swirl tank does get full of crud. This crud usually comes into the main tank with the fuel. The amount of rubbish in fuel, particularly if the fuel (gas) station underground storage tank level is getting low, has to be seen to be believed.

It is a good plan to take out the battery, remove the cover underneath the battery, and unbolt the swirl tank and clean it out. Almost certainly yours is full of rubbish, and maybe your main tank too. Undo the lock ring on the swirl tank and replace the 'sock filter' on the swirl tank outlet, which you will find inside.

Check the main tank by removing the spare wheel and undoing the lock ring holding the fuel gauge sender in place (ensuring the main tank is no more than 1/8 full, preferably less) and peep inside using a small torch (flashlight). If there is crud all over the main tank floor, you can probably flush it out by setting up a gravity feed system from the main tank outlet, and pouring filtered fuel though in from the inlet. CAREFULLY mind!

Once this all done, blow out and clean the fuel lines, injectors and fuel rail, replace fuel filter, and have a spare fuel pump handy, as that may have been damaged by the crud getting through. New lock ring rubber seals on the swirl tank and the fuel sender are important, too, and cheap enough.

Good luck

Greg

 

my fix for rusty tanks,etc.

plastic fuel cell 20gal. cleaned lot of rust from small tank, ended up with a bunch of small holes brazed them up PITA, thought about making one from aluminum, but alum. dont like Ethanol.

custom elec. fuel pump and filter combination, and FPR. all aluminum 1/2" lines and AeroQuip fittings. and etc,etc.

 

my first encounter with the red muck of death was when it clogged up the bowl in my Rochester 4brl.