outboard petrol in Cars?

tidclacy

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I have some left over petrol mixed with outboard oil for my two stroke. Rather than leave it to get stale over winter is it safe to put it in my car?

50 to 1 mixture.
 
I have some left over petrol mixed with outboard oil for my two stroke. Rather than leave it to get stale over winter is it safe to put it in my car?

50 to 1 mixture.

The worry is that the oil might contain something which will affect the catalytic converter.

I doubt very much if there is but as yet i have not sen an authoritative statement that there is nothing.

You can store fuel in a full tightly capped metal cans ie so that there is minimum contact with air, no possibility of loss of lighter fractions and no exposure to light.
I have done that regularly but I always filter it before use and mix 50:50 with fresh. I dont think I would do it with E10 fuel though

You can use it in garden machinery .

Or you can put in in my car as that does not have a catalytic converter.

Alternatively you can follow Sailorman's advice and bill him for a new "cat" if yours fails
 
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The worry is that the oil might contain something which will affect the catalytic converter.

I doubt very much if there is but as yet i have not sen an authoritative statement that there is nothing.

You can store fuel in a full tightly capped metal can ie so that there is minimum contact with air, no possibility of loss of lighter fractions and no exposure to light.
I have done that regularly but I always filter it before use and mix 50:50 with fresh. I dont think I would do it with E10 fuel though

You can use it in garden machinery .

Or you can put in in my car as that does not have a catalytic converter.

Alternatively you can follow Sailorman's advice and bill him for a new "cat" if yours fails


I am not a cat person, cant stand em
 
I use it ( 100:1 2 stroke, good quality oil ) in my car - which has a cat - each winter, no problem.

The local garden centre machinery bloke told me his big earner is people bringing in lawnmowers/ chainsaws / strimmers etc in the Spring which have been left with old fuel all winter; I have heard elsewhere from people I know are excellent engineers that modern unleaded petrol starts to jellify after about 3 months.
 
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I used to take my son Kart racing every weekend and only once did he put mixed 2 stroke fuel in our Car.............

The only weekend I was unavailable.

10 litres of fuel mixed at 15 to 1 ratio was enough to gum the piston rings solid resulting in serious piston slap and a destroyed cat.

I am talking about 10 litres of fuel in an empty tank followed by thrashing the car on the motorway for 3 hours.

I have happily put 5 litres in and then topped the tank up to the brim with fresh fuel since.
 
I put it (50:1 mix) in the car, but generally when the tank is nearly full so it's getting well diluted. Plus my car's only worth about £200, so it's not that big a risk :)

Pete
 
Thanks everyone, will probably use on my garden machinery. Don't want to risk any problems with my wife's petrol car. i would never live it down.
 
TSB240,

15:1 - Blimey, Seagull engines would be envious and Dylan Winter is probably setting a spell on you as I type ! :eek:

Air cooled 100 cc 2T race engines developing 22 to 24 bhp running super lean at 17,000 rpm with tuned scavenging exhausts need oil for keeping the soft metal bits cool and to stop bearings welding themselves up! Most races are over in less than 8 minutes of engine running!

Seagull probably caused more pollution when you tinkled the carb before you started it.
 
TSB240,

I understand and like the sound of it; however some here will be forming a lynch mob - I've never had a Seagull engine myself, just spent the odd night stuck afloat unable to get ashore because of chums having them...:)
 
The local garden centre machinery bloke told me his big earner is people bringing in lawnmowers/ chainsaws / strimmers etc in the Spring which have been left with old fuel all winter; I have heard elsewhere from people I know are excellent engineers that modern unleaded petrol starts to jellify after about 3 months.

Yes, you're right. But I recall, when I started driving, the elderly owner of our local garage saying that in 1945 he'd re-commissioned many cars that had been laid up for the duration of the war, and the petrol was fine in all of them.
 
The local garden centre machinery bloke told me his big earner is people bringing in lawnmowers/ chainsaws / strimmers etc in the Spring which have been left with old fuel all winter; I have heard elsewhere from people I know are excellent engineers that modern unleaded petrol starts to jellify after about 3 months.

In my garden shed there is 2 gallon can , now only part full, which contains 2 stroke fuel removed from my outboard engine fuel tank approx 12 months ago. It would have been a mixture of new petrol plus fuel stored from the previous year so in effect is probably around 1/3 petrol dating from 2011, 2/3 petrol bought during 2012.

I have been using that, with an appropriate quantity of extra oil added, this summer and as recently as last week in my Seagull . I do always run it through a gauze filter as a precaution but there is no sign of "jellifying" in that time and the "gull" has been running perfectly

I will not keep it any longer as I need the can to store petrol from the outboard tank again.

Conditions of storage are the important considerations I am sure. Leaving fuel in a garden machine fuel tank or even in a part full can is asking for trouble IMHO. I also believe that storing petrol in plastic tanks and cans may also contribute to deterioration.
 
Nigel, who used to post on here and was a fuel blender, said that it is daylight that causes to fuel to go stale. If you store it in the dark or have opaque fuel cans it should be OK. If you use modern plastic cans in daylight it will go off.
 
Good luck to all the "I've done it for years" chaps, but now theres corrosive ethanol in the petrol it has a much shorter shelf life.... and the proportion is rising.

I will be draining mine.
 
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