2 Stroke Fuel

[newchum]

troy
i ran the evinrude vro until i was talked into using premix.(every outboard mechanic said it was a breakdown waiting to happen) i still have the vro fuel pump connected but the oil circuit is disconnected. i buy 50:1 premix at the servo

[BaysideMarine]

I have used fuel older than 2 months and i never had a problem.
It was my previous motor being a 130 hp Evinrude and i had it for 8 years.
I might be lucky but #i know of heaps of people up here that do the same.
Just my thoughts and i think the idea off tossing out fuel that is 6 weeks old is going over the top.
Probably have put a curse on myself now.
Troy

Troy, every time this topic comes up either here or on fishnet there is always plenty that come out of the woodwork to say they use old fuel and suffered no ill effects.

Fair enough and you have been fortunate. But it is prudent and responsible for those in the industry to advise the public of the manufacturers recommendations.

It depends to a small degree on the type of engine, be it a loop charged or crossflow engine and then piston design also. If the engine in question was an older crossflow Merc with the high fin pistons you will melt pistons almost immediately with bad fuel.... Other factors such as propping, power to weight ratios and loading are also important elements.

But detonation due to stale fuel is real and it destroys engines.

Cheers

[BaysideMarine]

Re the disconnecting the VRO......

If you have the first released VRO (in 1984) it has no warning system chip fitted and hence, if it goes bung you wont know till you seize the engine....

However.... if you have the next released VRO which is clearly evident by the almost matchbox sized "box" sitting on the back of the VRo with wires coming from it. Early versions have 3 wires, later versions have 4 wires.

If you have a VRO engine with the electronics attached then they are wired to your warning system and as long as your buzzer works (easily tested) then keep your VRO connected.

Cheers

[NTMID8]

Sorry to bring an old thread back from the dead but.....

I am fitting an underfloor fuel tank to my boat, i have the space to go as large as 120ltrs but am thinking closer to 70ltrs, i have a 2 stroke evinrude with the VRO disconnected (premix) so how do i go if i dont use all the fuel in my tank?
How do people with 150ltr plus underfloor tanks go when they dont use all there fuel?
My warning horn works (beeps when i start the engine) should i have the VRO reconnected?

[Steeler]

I have only ever owned old Mercs with the high crown pistons and used fuel that has sat for up to 45 days with no detonation problems of the piston.I do use Stabil as a stabilizer and reckon this is a great product for preserving fuel for both outboards and outdoor power equipment.

Steeler

[BaitThrower]

Fuel Doctor is another great fuel stabiliser/conditioner that will keep fuel longer (prevents gumming/varnishing and helps disolve water and other furl bug in the fuel too).

[gr hilly]

i use all my fuel left over from my boat in my ride on, chain saw, push mower, and work vans, the mrs old holden, whipper sniper, and i find it makes a great upper cylinder lube.you can get out and walk on land.

hilly

[dnej]

well Hilly, you are heading for trouble. You cant, and shouldnt use , two stroke oil, , which is meant for water cooled engine, in an air cooled engine.
You need completely different two stroke oil.
David

[DATCOL]

I ad proma fuel treatment hav 200 leters under floor has sat for up to 6 months
with no problem 135 hp mariner oil injection 1994 model
COL

[NTMID8]

So as long as i add this fuel stabiliser i should be ok? Does anyone know what the build tolernace was of a 93 evinrude (silly question but i see the merc's had strong pistons, maybe the rude did too....)

[Steeler]

A lot of the older merc piston failures can be put down to incorrect timing particularly the inline 6's

Steeler

[gr hilly]

after reading some remarks on this thread i am looking at buying a new motor soon would it be wise to buy a 4 stroke motor this would have to do away with some fuel problems surely??.
Hilly

[NTMID8]

after reading some remarks on this thread i am looking at buying a new motor soon would it be wise to buy a 4 stroke motor this would have to do away with some fuel problems surely??.
Hilly

My understanding is it doesnt really matter so much about the premix (2 stroke) as much as it has to do with the fuel going stale.

[Spiderpig]

I have a merc 150hp EFI and a mariner 30hp carb both about 3 yrs old 300 hours each. I run spitfire in both motors when they need it but for different reasons.


The 150 EFI 2 stroke is not mixed fuel and doesnt make the engine run rough, but I do notice very reduced fuel consumption. If there is still a lot of fuel in the tank when I am ready to fill up I add a bottle or two of spitfire and top up with premium. (its a 260L tank) - this seems to pick consumption and range up a lot.

The 30hp runs rough whenever the fuel is more than about three weeks old, I add 100ml of spitfire to a tank. As soon as the fuel out of the line is burnt, the fuel in the tank is like fresh fuel. I can comment on consumption though as it uses sf all. My only other advice there is use premium and only fill up as much as you need.

[cormorant]

http://www.wynnswa.com.au/download/78701PS.pdf
http://www.wynns.net/product_files/S...3804%20PIS.pdf

Here is what's in it

http://www.wynns.net/product_files/S...701%20MSDS.pdf

http://www.wynns.net/product_files/S...804%20MSDS.pdf

You can not " sweeten" stale fuel. It degrades from the minute it goes in your tank.

You can up the octane but it may still leave you with waxes and gums in your fuel system or it may dissolve them and clog your filters.

Some of the treatments can mobolise water from the tank but if that fuel is then left in the injection system it can come out of solution and cause corrosion issues

Phone your petrol distributer and ask them what fuel stabiliser they suggest and put it in every tank of fuel you are not using in a marine environment within 14 days. They supply stabilised fuel to marinas and remote communiies so will know.