some symptoms of bad fuel?

[8v-of-fury]

Hi there guys I am trying to diagnose a running issue when run off the fuel that is in the fuel tank. The diesel is confirmed "Stale".

What does this make the motor react like? because I can't tell if it is the fuel or a blockage in the lines.

When run on a bottle of fresh stuff it will happily sit there and run well. When run of the fuel tank it will still run but slows to an, almost stalling, stuttering chug-chug-chug if i don't keep squeezing the primer ball that is conveniently located in my engine bay. However if I keep pressure on the ball, and i mean just barely touching it.. the engine won't almost stall.

What i wonder is can i just burn off this old diesel? I really don't want to have to drain the tank... I think i will just top it off... as the remainder is only around 1/4... topping it off with say some Diesel Power Service and a little ATF might do the trick.

[8v-of-fury]

as for the Diesel Power Service...

White Jug = Diesel Fuel Supplement +Cetane Boost

This is the product of choice for optimal winter operation. Diesel Fuel Supplement® +Cetane Boost® contains the most effective antigel additive package available in the diesel industry - no blending with No.1 diesel or kerosene is needed to achieve maximum winter protection. Diesel Fuel Supplement® +Cetane Boost® keeps fuel injectors clean and boosts cetane up to 4 numbers for faster cold starts and a smoother running engine.

Grey Jug = Diesel Kleen +Cetane Boost

Diesel Kleen® +Cetane Boost® is the premier “performance” product on the market. Diesel Kleen® is loaded with cetane, detergency and lubricity additives to keep your diesel engine running at peak performance.

If you are looking for an antigel, Diesel Fuel Supplement® +Cetane Boost® is the product you should be using. Like Diesel Kleen®, Diesel Fuel Supplement® contains a cetane and detergency package. However, it is not as concentrated as Diesel Kleen® to allow for the superior antigel in Diesel Fuel Supplement®.

Almost seems like White Jug is optimal for winter starting.. and Grey jug would be best for the most cetane boost and cleaning properties in the warmer months ! Now here's a question.. do they work as claimed? can anyone tell a difference?

[macka]

the winter stuff works very good, and the grey stuff is a treat for the shop truck engine. Its runs better.

[maxfax]

You had mentioned in another post something about fuel fligning form the timing belt..   If the pump shaft seal would be leaking it could be getting some air..   It'll take less suction to pull fuel from a jug than it would the tank..  Pumping the primber bulb would take some load off the pump too...

Excluding moisture or bacteria in the fuel, even REALLY old diesel will still run somewhat decent...

[8v-of-fury]

You had mentioned in another post something about fuel fligning form the timing belt..   If the pump shaft seal would be leaking it could be getting some air..   It'll take less suction to pull fuel from a jug than it would the tank..  Pumping the primber bulb would take some load off the pump too...

Excluding moisture or bacteria in the fuel, even REALLY old diesel will still run somewhat decent...

Crap Brett..... you do make an excellent point.. Guess I gotta fix the head seal on the 91's pump and swap it over! lol I probably freed up some shiet when i ran it on ATF.. same thing that caused the other pump to leak.. gawdd!

What is it like to change the pump shaft seal?... doable..?

[maxfax]

I would say that changing the shaft seal on that pump woudl be easier..   No need to completely remove the pump, just the belt and sprocket..     Just make sure there isn;t alot of play in the shaft..  I forget what exactly they say on that, but it isn't very much...

THey are about the same as changing any other seal, destroy the old one and remove, and drive the new one in there, preferably with a little lube on the shaft/seal.. 

[ToddA1]

About the grey jug....

I ran 2 tanks through the Rabbit when I first got it.  I was around 37mpg.  I did the 8 oz. quick clean as recommended, and still saw 37mpg. 

Each tank there after saw 3oz of Diesel Kleen.  Next tank saw 39mpg and the following fill up showed 41mpg.  I think I've only filled up 5x since I started driving the car in mid September.  I've only done a timing belt and air filter (about 3 weeks ago) and have yet to touch the injection timing.  New injectors and heatshields are also sitting in the parts stash.

I'm only using the 10 gallon tank capacity for my #s, so I may be getting slightly more than I advertised.  My #s may not be 100% accurate, but they should be consistant.  I usually run the tank pretty dry.

I guess if you do the math it's worth it.... $.60 worth of additive gains me what a gallon of diesel does.

-Todd