How old can fuel be ???

[dick_inc]

Hey guyz n gull's just a question for you smarty ack's out there , When is your pre mix fuel to old to use ? I have had a tank of fuel for about 6 months that I haven't had the time to use and seems like a waste to discard it, also can you revive it by adding more new fuel to it.????



Cheers Chris [smiley=2thumbsup.gif]

[caloundra]

about 3 months then it starts to deteoriate

[NeilD]

From what I have been told there is a measurable drop in Octane levels after as little as six weeks. There are products to stabilize fuel and they also increase the octane level. You may be able to top it up with Premium to boost it but I would be suss about running it through my outboard at 6 mths old.

Neil

[bj]

Mate,there was a time when I was in the same position and I syphoned about 80lts out of the tank and then added new fuel and 20 or so Litres of the old fuel plus a fuel conditioner and made sure that I did a fair bit of boating till the old fuel was finished. I had no problems but then I most probably would not say that I would recommend it,maybe I was just lucky and I make sure that I don`t get into that position again.

[lordy]

Serious question: where could you get rid of a large amount (30-150l). I've heard of people sticking it in mowers, but it would take years to use that amount in a mower. Massive bonfire?

[lordy]

Serious question: where could you get rid of a large amount (30-150l). I've heard of people sticking it in mowers, but it would take years to use that amount in a mower. Massive bonfire?

[lordy]

dbl post

[basserman]

i'v heard of people putting it in their cars as they say the cars fule system isn't quite as fussy BUT not sure i would be putting it into my brand new toyota might think about it is the car was say older than 6 years or if the fule looked and smelt alright :-/

[Morlers]

Would there be any problem in using say 10-20% of the old fuel in your car with the balance being fresh fuel?

??? ???

Morlers

[Kerry]

6 months and especially being pre-mix then extremely suss and one would use that at one's own risk.

Dilution is one way of using it up in small amounts and really you don't indicate just how much you have and in what type of tank. If it's been fully sealed and depending on the quantity then mixing with PULP (and appropriate oil) you might sneak it through in several batches but the decision is all yours.

Cheers, Kerry.

[baldyhead]

I got in touch with BP Technical 1300 130 027 and was informed that all I had to do was have a tote type tank of good (new ) premixed fuel to start my outboard on and when it was running switch over to my u'floor tank (fuel was about 8 months old ) and all would be well.
I followed these instructions and had no problems at all, burned up 150l of 8 month old premixed fuel and could not hear or feel any odd noises or lack of power etc.
I have done this 3 times now as above.
cheers baldy ;D

[NeilD]

If the fuel is not good enough to start my motor on I certainly would not use it. It is not a catastrophic big bang I worry about but the long term damage. I put some old boat fuel in my old Landy once and it played up something shocking ande fouled the plugs.

Neil

[Hagar]

Guys
Do not use pre-mixed outboard fuel whether it is old or new in any four stroke automotive engine . We used by mistake some pre-mixed outboard fuel in a four stroke compressor engine on a safari to the wide barrier reef once and it loosened carbon deposits from the cylinder head and lodged them under the valves requiring a bush stripdown . The result is likely to be the same in your automotive engine . Unmixed fuel for a four stroke or an oil injected engine could be used diluted with good fuel safely I reckon .

Chris

[dick_inc]

Thank's for your replys ppl , now I have to work out what to do with it, I don't think I'll put it in the car , it's in a plastic container about 50 lts, I might just try putting in 10% each time I fill up. once again thank you...

Cheers Chris

p.s were can you get rid of it if you wanted to ?

[NQCairns]

Hi Baldy, I is worried about you ;D It's your boat and your the skipper, so excuse the butting in but that is one hell of a gamble, dont know what motor you have also. In premixed fuel that old the oil has a habit of pulling itself away from the fuel and cannot lubricate as it should, if you were running 50:1 then you may have run 100:1 in reality. Hate to think what you were running if it is a 100 to 1 mix originally.
Then there is the octane loss over 8 months with a tank that is open to the atmosphere (via the breather). The only way a person could know if they did not do any damage is by a compression test before then after. Your motor should/would have been detonating the whole trip unless you retarded the timing to run that fuel. If it is a 6 cyl you are lucky you still have it IMHO. Ring that guy again and tell him you are taping the conversation and see what advice you get ::). At least you know that your motor is well tuned with no minor lean conditions or timing too advanced because it's still running fine. Just worried about a fellow FNQ'er is all.nq

[baldyhead]

Thanks for your concern NQ, I didn't use the spare tote tank of new fuel to start my outboard I hit the key & she started without any trouble. I mix my fuel @ 50:1 then put another 1/2 l of oil into the tank. ( a bit smokey on startup heheheh) I also give the boat a good rockin sitting on the trailer and it gets shaken up on the way to the ramps as well as when in the brinny the oil remixes with the fuel as can be seen when viewing the clear glass filter bowl. So I reckon that I'm goin ok at this stage. I have spent about 3 hours in the drink approx 4 klm E of Low Isles @ nite alone through no fault of mine some years ago until I was found and I certainly don't want to go through that again I can tell you.
So if I thought that there was any risk with the fuel BOY would I throw it out bloody quicksmart.
cheers Baldy

[moondancer]

Gotta say I'm with nqcairns! For the sake of 50 litres, what the hell do you want to take the risk for??? And it's not just about the motor not running well - it's short term, AND long term damage that you might not be aware of till it costs you big $$$ But the more important one IIMHO is safety - getting stranded out in the briny when you least expect it, and when you least need it . Imagine crossing a bar and the motor decides to foul????????

50 litres??

I'd rather be an environmental fool and use it to spray weeds in my gardem (only joking.....sort of!)

Oh - I would have the same views if it was 100 litres, or 200 litres!! (COS I'VE BEEN THERE!!)

Lawry

[blaze]

First up I top my boat up before each trip
So just a couple of thoughts.

Senorio 1
You go on extended holiday, leaving your 98 model car in the shed with half a tank of fuel, come home from holiday, jump in car on monday and go to work. you dont have a problem, bet you didnt change your fuel, fuel injected 4 stroke motor with advanced electronics

Senorio 2
Havnt used your boat for a couple of months, decide to drain fuel, put it in a drum. refill boat and go fishing.
2 months later you are told to mow the lawn before going fishing, thats right i got that drum of fuel somewhere i got outa the boat, ah there it is, fill mower, mow lawn, now we can go fishing, wonder how old that fuel will be used up.
thought I would through them senarios in the picture
cheers
blaze

[dick_inc]

I have got 50:1 mix and don't think the 4 stroke mower would like that....*S*

[landy1]

I guess the big qiestion is how do you dispose of 25ltrs of premixed fuel.
cheers
Mick

[NQCairns]

Your welcome Baldy, sounds like you have it worked out.
I have been stuck too but I did have company and we just fished, where you were 'lost' may be a lockout zone, would make the wait just that much longer :P. nq

[mulletguts]

just quickly guys there are companys out there that specialise in the removal and treatment of fuel and oil type products. Barkoola Environmental is one such company and another we use quiet regularly is Oil and Fuel Salvage here in Brisbane look under oil in the Yellow pages. For small quantities it's makes excellent parts cleaning fluid. Cheers ;D

[Kerry]

Really with a bit of planning one shouldn't end up with that much old fuel and certainly not enough that it should be a problem that can't be diluted.

For those that carry spare fuel, that is "spare fuel" that they hope to not use on the trip then don't oil it, carry the oil as required and simply put the straight fuel in the car after the trip or a month or so.

Anybody who doesn't know how much fuel they actually use under different conditions then maybe they shouldn't be there in the first place. So based on a trip one should generally know how much fuel they will actually use/require and obviously plan appropriately and arrive home with some up their sleeve.

If there's a third of a tank left then depending on the time factor either dilution with ULP or dilution with PULP if it's an extented period since last used.

Keep the tanks basically empty and omnly fill up immediately before a trip, forget the water/condensation concerns, not really an issue when compared to old fuel especially when one has good filters installed and maintained properly.

Better still if one can split what's left between several tanks then all the better.

The deal with old fuel in an outboard is not the same as a car that sits for a month and generally there ain't too many cars that sit as long as some boats do.

Old fuel really shouldn't be an issue unless one has put themselves in that position in the first place.

Cheers, Kerry.
#

[baldyhead]

nq I was in the drink swimming for Low Island, I could see the flash of the light reflecting off the clouds and just kept swimming towards it, luckily I was not meant to depart this life that early and was found by my father in the 1/2 cab that I was bounced out of at about 25 knots.
Fishing was the last thing on my mind at that time lol
cheers Baldy

[sir_noelus]

Hi, like usual this topic is probably dead by now? Last year we blew a cylinder in an old 115 merc when using 'less than six months' old PRE MIXED fuel. We mix our own. We rebuilt it, used the same aged UN MIXED fuel with new oil and blew it again after fifteen minutes. At that stage we changed to premium unleaded and also use a measure of Redex as well. All our engines (5 of them). 115, 40, 35, 15, and a six, all run on premium unleaded now with Redex and they are smoother and quieter than ever b4. Thank God we can do our own work. The total bill for both jobs was ony a few hundred dollars using second hand pistons. It was a different pot each time and there are questions whether it was the age of the fuel or just bad stuff. Can't prove one way or the other. Regardless, if the fuel is over 3 months, dump it. If you can't do your own repairs it's very expensive boating. Noel