Guys,

I have a few gallons of fuel from last season left over (not used for 5 months) - do you reckon it will still be OK to use or does it 'go off'???

It's a paraffin/oil mix not A1.

Rgds,
Mark

Here is a statement I found on the Shell Oil Web site, It may help.

All hydrocarbons degrade over time during storage. This "ageing" can be detected by a darkening of the fuel and the production of oil soluble gums. The fuel will also produce a fine sediment which can lead to filter or nozzle blocking.

If the container is completely filled, tightly sealed and stored in a cool, dark place, straight 1-K kero lasts a long time.....I used 10 gallons at Tucson Jets a few weeks ago that I purchased 3 years ago and stored in my hangar......looks good as new....no gum or debris....I do filter my older kero thru fine paint screens just to be safe........

Tom

Hi Mark.

I have resently learned the hard way..
I used 3 centistoke oil at 5% mix, and this was five months old, stored in a garage. But my turbine has to get some new bearings now, due to this fuel....
So I would not recommend using this fuel, just to be safe.
Ultraviolet rays and the mix itself, destroys the lube- capability of the oil, over time. It will be darker, but even a slight difference in colour, is a NO! So you will have to have fresh fuel to compare whith anyway.
Turbineoils are not made for mixing whith other liquids in the first place.
But I have never heard of others than me, having problems whith "old" fuel.


Gudmund

I have another question regarding fuel. A friend of mine owns several service stations and has informed me that Kero K1 is virtually the same as high cetane low sulpher Diesel #1. According to him the oil companies are trying to conserve costs and middle distillates like K1 and D1 only differ by the dye added so that DOT can burn a truck driver for using untaxed fuel on the road. Has anyone else heard of this? I have looked at the milspecs on JP5, JP8, D1 and K1. The JP5 and D1 are very close.

Hi Gordito.

You can use all the fuels you mentioned there.
JP8 is used on F-16 fullsize.


Gudmund

Holy crap Tom! I can't get 10 gallons to last me through a day at a jet event and you keep it hanging around for three years!

.

Hi Gudmund,

Thanks for answering. I never see anyone here talking about using Diesel #1, only Kerosene and Jet A. I have been told by other people before that D1 and K1 were the same but only recently did I research the specifications.

Thanks Again, Bill

David:

That old kero was hidden in one of my hangar cabinets.....every so often, the county air boss comes around and does a quick visual inspection of the hangars.....fire safety B.S. as usual....clean forgot about (5) 5 gallon jugs I had stuffed.....so, 48 flights later, the last of it is in my jug.....still have bearings singing in the 120's, so I think it is O.K....

If Scott Harris shows up at Mississippi and Tennessee, we'll give you a run.....pins permitting, of course.....

And as I seem to remember, fellow Wisconsin Jet Jerk, Brian French quietly logged 16 flights each day on Tuesday and Wednesday.......a load of algae-filled fuel shut him down when he was just getting warmed up, going for 20 on Thursday......

Heck, we have to match your kero burn up here in Wisconsin, not only to keep warm, but also to keep the earth from swapping poles..

T.......

Can any of you other experienced jet guys shed any more light on the interchangeability of Kero#1 and High Cetane Low Sulpher Diesel #1, has anyone done it here in the USA and has it worked?

Thanks, Bill

Gudmund

I must respectfully disagree with your comments. I have never in 7 years of turbine operations noted any degradation in turbine bearing performance as a result of " darkening " of my fuel mix due to ultraviolet. Contaminated fuel from airport underground tanks / field conditions, hygroscopic properties of kerosene and anaerobic bacterial growth are by far the leading causes of fuel delivery / combustion issues amongst turbine operators. As a general rule of thumb I keep my containers in a clean / cool / dry environment. I am particularly careful not to allow ANY introduction of water ( rain droplets ) into the container. As for fuel storage, I buy fresh in the spring ( Feb / March ) and try to use up all the fuel by the end of Oct. If some fuel is left over through the winter then I look at the bottom of the container to ensure no black spot formation ( anaerobic bacterial growth ) and go ahead and use it. I have used AeroShell 500, Exxon 2380 and Mobil 2 oils in RAMs, JetCats and PST engines. Further, I have never noted any separation of the mix, sludge, sediment or other particulate formation even after 18 months of storage.

Dean Wichmann
www.helijet.ca

Hi Dean.
I have checked my source conserning ultraviolet exposure.
Turbineoils has this ability to turn brown due to ultra, and this chemical reaction is almost instant. He said flightmeckanics use a ultraviolet lamp to make turbineoil brown, to detect oil-leaks.
If brown turbineoil can be connected to bad lubeability, is still not comfirmed. But I`m working on it. I`ll check whith a
lab soon( tomorrow).
As not only one, but two engines broke down in two days, there must be some correct in this. The fuel was only five moths old, stored in a garage / basement on a semi-transparent plastic can, and during wintertime.
The restrictors were fully open, checked the same evening, and the fuel was dark. How dark is hard to tell, as I don`t know how dark it can be. Lets say the colour was clearly changed.
The oil used was Turbonycoil 3 centistoke.
So how will you explain what happened? What are the possibilities?
I`ll be back as soon as I have contacted the lab at Statoil.
Se ya then.

Gudmund

Today I spent some time to investigate this issue.
Let me first say that I never ment fuel delivery or combustion issues would be a cause to the defect bearings I now have.

I have not yet been able to get in contact to flightmecanics, to briefly view into their respective service routins concerning oil-leak detection.

I have however spoken to different labs at Statoil, and one independent institution called`Cotax`, which is also a oil/research laboratory here i Norway. One of the labs at Statoil promised to e-mail me at a later time, but soon as possible.
I also planned to contact a instiution called `SINTEF`, but didn`t meet the right people today.
I`ll try again tomorrow.

Anyway, there was quite different answers...

The questions asked was:
1- What causes the fuel to change colour during some time?
2- Is the reaction a sign of degraded lubrication-ability?
3- Does turbine-oil react in any way as a cause of ultraviolet radiation?
4- Is anaerobic bacterial growth a vital factor for the lube-ability?

The first lab at Statoil answered like this:

1- Does it? I have never heard of turbine-oil used this way before.
The oil is made to lubricate gas turbines in a enclosed system, but
I`m surprised i does.

2- It might be, as the oil is not ment to be used like its in the first place.

3- Its the first time I`ve had that question, but it might have this sideeffect, but
is not that I`m aware, a inbuildt quality.

4- No, usually not in any oiltype. But bacterial growth is a danger to
filters, which can be blocked.

In my hunger to dig for proper answers, I`m waiting for the reply from the other Statoil lab in Stavanger. This was promised to me as a e-mail.
The third and last lab `Cotax`, answered like this:

1. If the fuel changes colour over a time of period, it`s certainly a sign of
changed capabilities.
The syntetic esther based oils are full of additives, which each and together
have given the oil its quality. The brown colour is most certain a sign of
oxydation to one or several components.

2. Degrading one or several components, means the oil no longer to comply
to the referring data-sheet. You can lo longer be sure of it`s quality.
I would suggest not to mix moore fuel that you expect to use, or find
another brand. ( I then said this seemed not to a issue to other brands, as I
seem to be the first whith this problem).
I would like to say you use a turbineoil which has a lower level of recistance
to hostile environments, but this can only be prooved in a test compared to
other brands. I can however take a acid-test to measure the acid-level in it.
This will for sure tell whats wrong. This will cost you at least NOK 1500, but
will give most of the answer you want to know.
The other brands seem to still keep high enough quality to your use of it,
but is never the less suffering of some degree of degrading.
It must be, as long it`s oxydated.



3. No, I would not think so. Have never heard if it.

4. No, it`s not. If the amount of anaerobic bacterial-growth is not larger than to
be absorbed by filters, this is not seemed as a big problem. The best
temperature for it, is about 60 deg Celcius. Temperatures below 50C is not
suitable for anaerobical growth, and would be cept to a minimum. This need
heat and water. Most turbine oils can contain 6-800 PPM (600-800??)of
water, whithout beeing detected by eye. ( I
don`t know what measure this means...)



I`m still not to the bottom in this issue as it rises moore question the moore I dig in it.... Anyway, a very comlex topic.
This last person at `Cotax`, seemed quite convincing over the phone, and was a person I felt was skilled at a high level.
I guess the theory about the ultraviolet is hanging by a thin thread, but it would be interesting to track this even furter. Normally, most plastics easily blocks any UV radiation, but i know there are some who don`t.

If I discover any other `news`conserning UV and other factors, I will hang it up here later.
So this was a days work as an electritian
I learned alot, and I`m changing to another brand like the rest of you guys, as it seems to be the remedy

Gudmund

Hi Bill

Your Diesel/Kero question. The only infromation I can find is that Kero is added to diesel to lower the "freezing" point of the diesel. The diesel does not actually freeze but forms a wax which clogs in the filters and the engine will no longer run. The maximum amount of kero to be added to diesel is 10%. Thereafter the lubrication of the diesel is not sufficient.

Regards

Zane

Zane,

Thanks for the response. I just wonder how often we may think that we are getting Kerosene from a pump and it is actually something else, such as a mixture of middle distillates.

Bill

Mark,
Coming to the jet meet?

L

Invitation only I believe - am I invited?!