Fuel age and mixing

Page  12>
Post Options Post Options   Likes (0) Likes(0)   Quote MikeAqua Quote  Post ReplyReply Direct Link To This Post Topic: Fuel age and mixing
    Posted: 20 Feb 2018 at 10:20am
MikeAqua View Drop Down
Platinum
Platinum
Avatar

Joined: 29 Jul 2008
Location: Nelson
Status: Offline
Points: 2278
Due to recent surgery (nothing serious)  I haven't been boating in several months.  I have two totes of 50:1 premix that are at least 4 months old.  They have been stored indoors at all times.

I plan to mix it with fresh pre-mix.

My questions are: -

A) How old is too old?
B) Is a 1:1 mix with fresh fuel sufficient dilution of the old fuel?

Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote Tagit Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 10:28am
Tagit View Drop Down
Titanium
Titanium
Avatar

Joined: 21 Aug 2003
Location: Westhaven, Auck
Status: Offline
Points: 15052
4 months and non-ethanol I would mix 50/50 with fresh high octane fuel. 4 months stored out of the heat etc is probably still marginally OKso top it off 50/50 and I think you should be good to go. If it is ethanol blend fuel though I would probably dispose of it rather than trying to use it.
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote MikeAqua Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 11:15am
MikeAqua View Drop Down
Platinum
Platinum
Avatar

Joined: 29 Jul 2008
Location: Nelson
Status: Offline
Points: 2278
No ethanol and it's 91 so should I top it off with 95 or similar?
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote JustAnotherSpearo Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 12:18pm
JustAnotherSpearo View Drop Down
Platinum
Platinum


Joined: 12 Mar 2016
Location: Northland
Status: Offline
Points: 1189
Id be chucking a bit more oil in and slapping it into the lawnmower. But two tote tanks would be nearly half of whangarei mowed.
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote pjc Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 1:06pm
pjc View Drop Down
Titanium
Titanium
Avatar

Joined: 04 Apr 2010
Location: papakura
Status: Offline
Points: 12468
use it in the car??
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote MikeAqua Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 1:08pm
MikeAqua View Drop Down
Platinum
Platinum
Avatar

Joined: 29 Jul 2008
Location: Nelson
Status: Offline
Points: 2278
Originally posted by pjc pjc wrote:

use it in the car??


Censored  no! 

The car is only three years old. 

Not sure how its electronic wizardry would cope with oily petrol.
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote MikeAqua Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 1:20pm
MikeAqua View Drop Down
Platinum
Platinum
Avatar

Joined: 29 Jul 2008
Location: Nelson
Status: Offline
Points: 2278
Originally posted by JustAnotherSpearo JustAnotherSpearo wrote:

Id be chucking a bit more oil in and slapping it into the lawnmower. But two tote tanks would be nearly half of whangarei mowed.

I fill up the 5L can about twice per year. So two totes is 4 years worth.


Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote Dagwood Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 2:01pm
Dagwood View Drop Down
Platinum
Platinum
Avatar

Joined: 17 May 2003
Location: New Zealand
Status: Offline
Points: 2296
Originally posted by JustAnotherSpearo JustAnotherSpearo wrote:

Id be chucking a bit more oil in and slapping it into the lawnmower. But two tote tanks would be nearly half of whangarei mowed.

Careful, outboard oil isn't designed to cope with the temps of an air-cooled engine.

Bit of a myth that lawn mower / chainsaw two stroke oil is simply inferior to outboard oil.
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote Dagwood Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 2:03pm
Dagwood View Drop Down
Platinum
Platinum
Avatar

Joined: 17 May 2003
Location: New Zealand
Status: Offline
Points: 2296
Originally posted by MikeAqua MikeAqua wrote:

Originally posted by pjc pjc wrote:

use it in the car??


Censored  no! 

The car is only three years old. 

Not sure how its electronic wizardry would cope with oily petrol.

I've run a bit (say 15 litres at a time) of 50:1 in a 2012 Rav 4 with no issues...
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote MikeAqua Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 2:29pm
MikeAqua View Drop Down
Platinum
Platinum
Avatar

Joined: 29 Jul 2008
Location: Nelson
Status: Offline
Points: 2278
Originally posted by Dagwood Dagwood wrote:

Originally posted by JustAnotherSpearo JustAnotherSpearo wrote:

Id be chucking a bit more oil in and slapping it into the lawnmower. But two tote tanks would be nearly half of whangarei mowed.

Careful, outboard oil isn't designed to cope with the temps of an air-cooled engine.

Bit of a myth that lawn mower / chainsaw two stroke oil is simply inferior to outboard oil.


Presumably OK in a 4-stroke mower?
Back to Top
Post Options Post Options   Likes (1) Likes(1)   Quote Reel Deal Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 2:31pm
Reel Deal View Drop Down
Titanium
Titanium
Avatar

Joined: 28 Sep 2003
Location: Whangarei
Status: Offline
Points: 3849
give to a guy who has a 2004 Johnston Bombader 115HP outboard like me.
I chuck all ages of gas through it old, new, oily, lean...just burns it no probs. Motors been fine for 10 years doing so...basic but powerful engine. I had it sit over a year (I lived over seas for a time)with underfloor tank half full and two tote tanks in a carport. Started second attempt blew a bit of smoke as 2 strokes do then went on a 5 hour trip no probs.

Been trying to upgrade to a nice new Honda four stroke but these motors appear indestructible!
The gods do not subtract from the allotted span of men's lives the hours spent on fishing - Assyrian Proverb
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote MikeAqua Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 2:42pm
MikeAqua View Drop Down
Platinum
Platinum
Avatar

Joined: 29 Jul 2008
Location: Nelson
Status: Offline
Points: 2278
I am tempted to just run the outboards on it 50% diluted with fresh premix.

But then ... it's $80 of fuel.  Why risk a problem.

BTW what problems does old fuel actually cause? 
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote Dagwood Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 2:56pm
Dagwood View Drop Down
Platinum
Platinum
Avatar

Joined: 17 May 2003
Location: New Zealand
Status: Offline
Points: 2296
Originally posted by MikeAqua MikeAqua wrote:

Presumably OK in a 4-stroke mower?

I would think so. 
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote Steps Quote  Post ReplyReply Direct Link To This Post Posted: 20 Feb 2018 at 4:05pm
Steps View Drop Down
Titanium
Titanium


Joined: 14 Oct 2013
Location: Franklin
Status: Offline
Points: 12849
Steel or Plastic totes? Steel will be ok.. only possible, maybe issue little hard starting.... maybe. If so that haw you will know it has lost some of the more volatile parts of the fuel.

 Ethanol blends require far morew of the 'start up' blend, far more prone to 'going of' and picking up humidity water..
 Decant, check any water laying in the bottom of the tank, and blend with std non ethanol as above.

 Note: If you have a good water filter in the fuel line, this will remove the little bit of water that maybe in the bottom of the tank.  The fuel pick up will suck it up 1st, then dump it in the filter.

 Best bet, simply go 50/50 with fresh fuel... 25% even.
Its only the volatile additive part that enables easy start may have  perminated thru a plastic container, thats partly gone.

give to a guy who has a 2004 Johnston Bombader 115HP outboard like me.

 Yep damn solid engine..sold mine late last yr, 'upgraded' to  just run in 150 HP V6
Coincidence... got the

 "2004
Operator's Guide
 90 THRU 175 HORSEPOWER "
PL, PX, CX, GL "

 laying on the desk in front of the monitor in front of me..

Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote MikeAqua Quote  Post ReplyReply Direct Link To This Post Posted: 21 Feb 2018 at 11:01am
MikeAqua View Drop Down
Platinum
Platinum
Avatar

Joined: 29 Jul 2008
Location: Nelson
Status: Offline
Points: 2278
Originally posted by Steps Steps wrote:


 Best bet, simply go 50/50 with fresh fuel... 25% even.


Is that 25% new or 25% old?
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote Muzzfishing Quote  Post ReplyReply Direct Link To This Post Posted: 21 Feb 2018 at 5:29pm
Muzzfishing View Drop Down
Platinum
Platinum
Avatar

Joined: 17 Jul 2002
Location: Cambridge NZ
Status: Offline
Points: 2550
Was in the local boat shop mechanic was syphoning out the petrol tank, asked him why said petrol was old 6 months, boat was been serviced. I dont like to keep petrol in a can for more than a month for the boat. I take extra petrol when out trolling boat has 80l under floor. So after a month in plastic container syphon into main tank. And refill tote when going out trolling. Use my boat regularly so getting fresh petrol in tank.
 Any surplass petrol in tote tank goes into the lawn mower.
    A Good Skipper Keeps the water on the outside of the boat.
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote ofthesea Quote  Post ReplyReply Direct Link To This Post Posted: 21 Feb 2018 at 10:52pm
ofthesea View Drop Down
Silver
Silver


Joined: 12 Dec 2006
Status: Offline
Points: 426
But has anyone actually had anything bad happen other than being hard to start after a while?
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote MacSkipper Quote  Post ReplyReply Direct Link To This Post Posted: 22 Feb 2018 at 7:18am
MacSkipper View Drop Down
Titanium
Titanium
Avatar

Joined: 04 Jul 2014
Location: Manukau Harbour
Status: Offline
Points: 4478
Originally posted by ofthesea ofthesea wrote:

But has anyone actually had anything bad happen other than being hard to start after a while?
Isn't that bad enough?   Would be for me very embarrassing as have the perfect day to get out and hard to start, or really dangerous as pulling anchor because a big launch bearing down on you and wont effing start!
Good fishing trip nothing breaks, great trip catch fish.
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote Silver Slayer Quote  Post ReplyReply Direct Link To This Post Posted: 22 Feb 2018 at 7:25am
Silver Slayer View Drop Down
Bronze
Bronze
Avatar

Joined: 25 Aug 2014
Location: Hatfields Beach
Status: Offline
Points: 79
If my premixed fuel has been sitting for longer than 2 weeks in their tanks I give them a good shake. With the secret squirrel additives petrol companies mix into petrol you just don't know how quickly the 2 stroke oil separates. If my premix is older than 6 weeks I'll pour it into the car. However I make sure the car has a half tank of gas to reduce the oil ratio.

Stale fuel doesn't just cause harder starting but also rougher idling, detonation issues, power loss, plug fouling and carbonization. I would rather prevent this loss of performance in my 2 stroke engines and keep them running in tip top condition by using fuel less than 6 weeks old. I can't speak for outboards as I haven't stripped one down to that level but I've done a few topends on performance 2 stroke dirt bikes and yes you can see the damage caused by a dirty burn on the piston, sleeve and exhaust port. I'm not saying damage was caused solely by stale fuel as other factors may be involved, typically overheating or worn rings, but it does contribute. eg. a rough running engine caused by stale fuel creates unneccessary wear and load down the power train. Meanwhile the problem is misdiagnosed and someone tutu's with the engine, zoning in on the carbs thinking they're the issue. Burn goes leaner and down the slippery slope you go....incorrect operating temperature, worn rings etc

However, if you do go ahead and use it, as Steps suggests, the more fresh mix you blend in.. >50% the better.

My 2c
Back to Top
Post Options Post Options   Likes (0) Likes(0)   Quote Steps Quote  Post ReplyReply Direct Link To This Post Posted: 22 Feb 2018 at 7:54am
Steps View Drop Down
Titanium
Titanium


Joined: 14 Oct 2013
Location: Franklin
Status: Offline
Points: 12849
Is that 25% new or 25% old?

 old

But has anyone actually had anything bad happen other than being hard to start after a while?

 
Yes.. not boats but within hot rod band classic / vintage car clubs.
 Comes about after long periods of storage, 12 months plus.
 And when tanks tend to be less than 1/2 full.
 General rule of thumb, store way with only a gallon or so in the tank... Drop a container of 5 or 10L in if hard to start.
 That quantity is because most petrol cans are that size Big smile
Also general rule is to fill up on the way out.. be it a car or boat.. NOT on the way home.
 If you dont have a fair idea how much fuel you used  for the day... use the boat more often Wink
 Since the introduction of unleaded petrol in NZ.. late 80s from memory, only know of 1 instance where got the 1950s car running  and was miss firing... and that very strongly suspect due to condensation in the distributor .. not fuel.
 Had been stored for 3 or 4 yrs.
Back to Top
Page  12>
Forum Jump
Forum Permissions View Drop Down


This page was generated in 0.383 seconds.

Fishing Reports Visit Reports

Saltwater Fishing Reports
Top of the South Fishing Report - 22/03/24

Tasman and Golden Bay snapper still running hot We are not far away from daylight... Read More >

22 Mar 2024
Saltwater Fishing Reports
Bay of Islands Fishing Report - 22/03/24

Variety is the spice of life On one recent trip, the plan was to spend a... Read More >

22 Mar 2024
Saltwater Fishing Reports
Hauraki Gulf Fishing Report - 22/03/24

Fish where the fish are! Catching fish or just going fishing? I tackle this issue... Read More >

22 Mar 2024
Saltwater Fishing Reports
Inner Hauraki Gulf Fishing Report - 22/03/24

Thoughtful tactics required for better fish Over the course of each year the fishing varies,... Read More >

22 Mar 2024
Fishing bite times Fishing bite times

Major Bites

Minor Bites

Major Bites

Minor Bites