Running outboard on 5 year old petrol

westernman

westernman

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Last week we dug the outboard motor out of the depths of the stuff hidden away in the boat. We had not used it for two years - and the petrol was 5 years old.

I was very surprised when it started on the very first pull - and I was not even pulling seriously - I was just testing to make sure nothing was seized.

However, to run smoothly the outboard requires a fair bit of choke. This is not normal. Is this due to the old petrol in some way - or something clogged up in the carbouretter?
 
As suggested ditch the old petrol and replace with fresh.

If it runs OK problem solved, othewise start cleaning the carb!
 
The problem is finding some one/some thing to donate the old petrol to.

I don't know anyone close by with a petrol car, and my mum's lawn mower is unlikely to appreciate the old stuff..........

May be I can fill up the tank of the neighbour's sit on lawn mower without him noticing......
 
jwilson said:
Before you throw away the fuel, try stripping and cleaning the carb. Petrol's probably fine.
Click to expand...

It is not its value I am concerned about - we are after all talking about 3 litres left over in the motor and in the refill canister. But about how to get rid of it!

If there is an easy why to chuck the old fuel and try running on clean stuff I would rather do that instead of starting to dismantle an engine which is actually running fine.
 
michaelchapman said:
It is not its value I am concerned about - we are after all talking about 3 litres left over in the motor and in the refill canister. But about how to get rid of it!

If there is an easy why to chuck the old fuel and try running on clean stuff I would rather do that instead of starting to dismantle an engine which is actually running fine.
Click to expand...

I always store fuel from one season to the next. But I only store full metal cans. (No loss of low Bpt fractions, minimum contact with air and no exposure to light.

Before using it I filter it. Only once had trouble... and that was the one time I did not filter it. removing and dismantling a carb to clean it in the dark, rolling all over the place on one of the buoys off Cowes is not to be repeated!
I also mix 50:50 with fresh.

I have never tied to use fuel that is 5 years old!

I thave tried to run the old Flymo on some of the rubbish ... it does not like it. Nor does the Seagull

Got a petrol engined car without a 'cat'. That's where stuff to be disposed of goes
 
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michaelchapman said:
It is not its value I am concerned about - we are after all talking about 3 litres left over in the motor and in the refill canister. But about how to get rid of it!

If there is an easy why to chuck the old fuel and try running on clean stuff I would rather do that instead of starting to dismantle an engine which is actually running fine.
Click to expand...
I think the engine is not actually "running fine" if it needs choke for more than a few seconds. The fact that it started easily probably absolves the petrol from responsibility for the poor running. Clean the carb....
 
I went through this nightmare I bought a boat with VERY old petrol in it. The Tip would not take it not would the Fire Brigade I litrally had no place to take it...

Maybe it goes the same way as old flares? Into a Police station in an old can? I found this beside the road?
Or take it to the local marina waste oil tank at a quite time? If you are doing an oil change maybe mix it in?
Have you got some where you can burn it?

If not you could dilute it with fresh petrol but it might give you a bigger problem!

I agree about trying fresh petrol before stripping carb. Have you got a can you can put it in as standby to try fresh petrol?
 
michaelchapman said:
It is not its value I am concerned about - we are after all talking about 3 litres left over in the motor and in the refill canister. But about how to get rid of it!
Click to expand...

I had 5 litres of last years fuel left over, but being fairly anal about running the engine on fresh fuel I had exactly the same issue.... there's nowhere you can get rid of the stuff... in the end I took it down the tip in the petrol container and put it in one of the bins.... :o
 
A few ltrs even 5 put into the cars fuel tank (so long as its a petrol engine, did I really need to tell you that?) mixed with another 60 ltrs will do no harm to the car, and gets rid of the fuel.
 
Sounds like the main jet in the carb is partially blocked. It's very unlikely that it won't have to be unblocked.
I would think the petrol is either ok or not ok. if it's 5 y/old it possibly doesn't contain all the additives that cause age related problems with stuff bought now, depending on where it was bought.
CJ
 
I'm not sure when "biofuels" were added to unleaded in the UK. It's quite common (sadly) for these to gum up small carburettor jets and after a 2 year lay off, that's be my take. Older systems have components that react badly to ethanol so check with the manufacturer's website. If the fuel is 5 years old, how old is the motor? The carb can be striped and cleaned with an aerosol cleaner, most motor factors sell them. As for disposing of the fuel, five litres in a tankfull of fresh will see it through the systems of even a modern car. My wife's Moggie Minor thrives on old 2-stroke, it's better than Redex.

Garden machinery has small to tiny carbs, the choke on my Honda mower is about 12mm, my Ryobi strimmer closer to 6 (no i've not measured them) and the jets are correspondingly small so a little "gum" goes a long way.
 
Ceejay said:
Sounds like the main jet in the carb is partially blocked. It's very unlikely that it won't have to be unblocked.
I would think the petrol is either ok or not ok. if it's 5 y/old it possibly doesn't contain all the additives that cause age related problems with stuff bought now, depending on where it was bought.
CJ
Click to expand...

I have a 2.5 four stroke Suzuki that has this problem. I have cleaned to carb bowl - lots of crystals in there, but it is still a bastuard to get get to idle.

So how do you clean the main jets if you don't have compressed air around? Or could it be the idle jet??
 
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