water in fuel system

30csl

30csl

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Hi guys, this is not on the coupe but a r107 sl 280. My brilliant brother managed to throw a gallon of water in thinking it was fuel. I felt her running rough so filled her up with fresh fuel. Car kept running for a while but then died.

I pumped all the fuel+water out and put in fresh fuel and now she runs rough. I plan to clean the injectors and plugs.

Anyone got any tips for stuff to put in the fuel to help remove the water? My father said methylated spirits? I had the pump and filter out last autumn and don't have the will to strip it all again to clean it out.

Many thanks,

Rohan
 
If you can get "dry gas" which is high percent alcohol. Alcohol will burn even at lower percentages and will attach to the water.
 
Keep in mind that methanol is much more corrosive than ethanol. Both will attract water but one is much more detrimental to your engine than the other. Also, the stoichiometric ratio of air to fuel also varies depending on the fuel type. For gasoline combustion it is 14.7 air to 1 fuel. For ethanol combustion it is ~9 air to 1 fuel. That means that you need to be more "rich" as the percentage of ethanol in a gas/EtOH mix increases.

I'm not familiar with the 280SL (and don't know if it's mechanical or electronic fuel injection) but if it's EFI and there are multiple fuel setting, go for a rich setting and either add EtOH to the fuel or find and EtOH rich fuel (sorry if I'm vague about the ratio but someone more familiar with the topic should be able to chime in). By the way, the octane for alcohol fuels is rather high compared to gasoline (E85 is min. 105 octane) which means that your shouldn't experience knock (as long as stoich is correct).

In short: avoid methanol. If you run pump gas with 10% EtOH you should be ok. If you mcuh run higher than that you need it to be "richer."
 
Brilliant help - thanks guys - i guess its an excuse to get the injectors cleaned/overhauled anyway - they havent been touched and she has done 175k miles so not premature!

Regards,

Rohan
 
I gotta know how the water went in. Was it a hose? Bucket? Will you ever let him forget this?

Gas line antifreeze has worked well for me when removing some water from my fuel system.
 
Nicad, you wouldnt believe it - my old man is the sort who tries to revive dead batteries only to have them explode and ruin lovely cars! So when he saw a can of 'fuel' in the garage he decided it was petrol and threw it in.

I wouldnt mind but i have just been through the back end fuel filter and lines etc.

Still struggling with it and have decided while i am to get the injectors cleaned.

Try and turn bad good! Going to throw a bottle of IPA in it which seems to be in the UK what you guys are calling dry gas.

Thanks again,

Rohan
 
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