Gasoline Filter/Water Separator

[Sam Elkins]

Thinking of getting a water separator and was looking in the West Marine catalog. They have them from about $60 (Racor)to $30 (Sierra). The Sierra says it a replacement for the Mercury separator. The Racor does have a see-thru bowl whereas the Sierra doesn't. Does anyone have one and would there be a performance/protection difference between them? I know $30 is not a lot of $'s but no need to spend if not necessary. Any comments would be appreciated. Thanks

 

[Staci Matheis]

Sam -



Even in aircraft (at least private), where pure fuel is so very important, they don't have seperators; they simply have a petcock in each tank that you open and check for water each time you prepare for a flight.



Keep your tank full in the cooler/colder months to prevent condensation and add a can of "Heet" maybe once a year.



That should be more than sufficient!



me!

 

[Bill P]

I think gas treatments, like Heet, drygas, etc: are not supposed to be used for outboards, because they contain alchohol, and owners manuals tell you not to use any additives with alchohol in them. I guess where the gas tends to sit in the fuel lines for periods of time, the alchohol can eat away at the rubber, or dry them out. Check your owners manual, before using any additives. JMHO

 

[Staci Matheis]

Bill -



Twenty-five years or so ago, when some of the oil companies first started adding grain-based alcohol to the fuel this was so....... The material that the floats in the carburetors were made of absorbed the alcohol, they became fuel-logged and lost their bouyancy. The solution was simple - carb manufacturers changed the composition of the materials to those that were impervious to the alcohol.



There was also a fear that the alcohol might wash down the cylinder walls on 2-cycles removing the oil deposited there by the fuel. Again, ungrounded. Gasoline is, itself, a very powerful solvent and it is this property which actually helps the oil to completely and thoroughly coat the cylinder walls.



me!

 

[Duart Betz]

Actually, Mercury's fuel system treatment and stabalizer and the dri-fuel additive both contain ISOPROPYL alcohol.

The isopropyl alcohol absorbs water in the fuel and passes it harmlessly through the engine. I think it is the ethanol and methanol alcohols that are hard on the fuel system.

 

[Mark Hofman]

I agree with Duart.



Also, some types of alcohol (and I think this depends upon how refined it is) leave water behind when the alcohol is burned away. Even isopropyl alcohol will leave some water residue behind if you light a small bowl of it on fire.



Now, I am NOT a mechanic - but if the absorbed or latent water level is high enough, wouldn't it flash to steam in the combustion chamber and boost cylinder pressures over the designed tolerances?



If I were spending money on a water seperator, I'd get the see-through one. I'd want to eyeball that thing, without having to take it apart, to see if there is water in my latest tank of fuel so that I could avoid that source in the future!



Mark