Stained Bottom

[skippydiesel]

A vinyl wrap on the area may protect the skin and can be easily removed when necessary

Sounds interesting - would involve an almost full length piece (s) from just aft of the engine to the tail - where would I find this stuff ??

 

 

[Downunder]

I wonder if the cause is some additive in the fuel. Which brand of fuel do you use regularly? Maybe it's the stuff that BP and Shell add as a cleaner and the stain is an accumulation over time of the cleaner and anything it has removed from tth engine.

Yes, I believe it is something in the fuel(95/98). The staining is very similar to staining from spilt fuel at the filler, from venting or spillage.

 

As the ULS is carby fed, I'm thinking it is excess fuel coming through the exhaust, perhaps at idle or low rpm on decent. They are know to be very rich in this rpm range.

 

 

[onetrack]

Both the basic diesel and petrol fuels from all the oil companies is "generic". The very largest proportion of our diesel and petrol used in Australia is refined overseas, in South Korea, Japan, Indonesia and Singapore.

 

Less than 40% of our petroleum fuels are refined in Australia, and Kwinana in W.A. is the biggest local refinery, because it is the newest (1954) and largest of all the Australian refineries.

 

The refined product is produced to meet Australian fuel specifications, and from overseas, it is shipped in bulk and stored in bulk tanks at fuel farms that are mostly located close to ports. These bulk tanks also hold the locally-refined products.

 

The petrol and diesel is then trucked in bulk from fuel farms to distribution centres and service stations.

 

The oil companies supply each other with generic fuel in cases of shortage or other distribution problems, and several oil companies will draw fuel from the one bulk tank at the ports.

 

Where an oil company has a distinctive "premium" fuel with a brand name, a price increase, or an octane/cetane increase, it is because the particular oil company has added an "additive" package to the generic refined fuel at the point of tanker truck fill.

 

These additive packages are commercially secret, but we know from research they contain a range of somewhat exotic (mostly petroleum) chemicals, that all provide a power boost, improved economy, and fuel system cleaning advantages.

 

Not surprisingly, there are also some "oddball" chemicals in the additives. Selected essential oils from organic sources are a surprisingly effective fuel additive, and commonly used as a fuel improver additive.

 

The oil companies have done extensive testing with their premium fuels and have the figures and testing to back up their claims for improved economy, improved performance, and cleaner fuel systems when using their premium products.

 

I would have to opine the additives in the fuel additive packages are the source of the staining. If these chemicals are impregnating themselves in the paint, it is a chemical reaction taking place between the additives and the paint, and no amount of cleaning will remove the marking.

 

I'd suggest the vinyl wrap is probably the most effective method of curing the problem. However, be aware that vinyl products and the adhesives they utilise, also react with paint coatings, effectively bonding and impregnating the vinyl into the paintwork after a number of years and weather exposure.

 

Try removing vinyl decals from vehicle bodies after they have been in place for several years, and you will find it is virtually impossible to remove them, without damaging the paint.

 

 

[facthunter]

Bromine to remove lead deposits in 100 LL is an example. That is what causes the whitish coating in the exhaust pipe if your engine s not idling too rich. Nev

 

 

[old man emu]

Onetrack suggests a replaceable vinyl coating. Sounds a bit like a nappy to me!!!

 

 

[Downunder]

...

 

 

[onetrack]

Hey, I've got a suggestion. Skippy could just let it all go, until the finish has developed a "patina", that makes it an outstanding aircraft - you know, "Hey, what's that rustbucket doing here?? Does he actually fly that thing??"

 

Well, if it's good enough for the hot-rodders, so they can stand out amongst the candy-apple paint jobs - why not your aircraft??

 

 

[spacesailor]

Just to let you know, if wanting "Wrap"

 

Facebuk marketplace has a advertisement for cheap vinylwrap.

 

"$100 For a 30m roll 1.52m wide. Please look at all the photos these are the colours I have left let me know what you want will do cheaper if you buy several rolls. Will sell the whole lot together. Don't just ask if it's available tell me what you want and when you want to pick it up. Located Blacktown. I'm getting rid of all my vinyl cheap prices. No black or white colours left. Camo green red pink purple yellow carbon fibre Metallica available. Black carbon fibre available. Full rolls available in 30m lengths. Pickup Blacktown. Suitable for cars bikes or whatever. Air release material. Tags Mazda Holden Ford Mitsubishi Toyota vw datsun race car boat jet ski Golf evo lancer xr5 falcon Commodore laser xr6 turbo vl 6 3 "

 

If this is what you are referring to.

 

spacesailor

 

 

[old man emu]

Hey, I've got a suggestion. Skippy could just let it all go, until the finish has developed a "patina",

Then he'd have to change the title of this thread from "Stained Bottom" to "Black Bottom".

 

 

[pmccarthy]

A skid mark is a skid mark is a skid mark.

 

 

[old man emu]

Yellow Brick Road

 

 

[Tecsar]

"X-IT Carbon Remover & Cleaner" works well for me.

 

 

[skippydiesel]

Skippy, have you got a close up photo of the Staining ?

 

Jason

Sorry Jason - not long given the girl a good scrub. Staining now so faint it doeskin show up in a photo. Next time I clean her, I will do a contrast photo for posting - that way you will see the actual exhaust contamination against a cleaned area