Water separator filters

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dollelliott

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Has anyone had any experience with the water separating filters which replace an ordinary fuel filter for gasoline engines? Do they inhibit any problems with ethanol? Are any brands any more efficient or convenient to service?
 
I use only gas/water separation filters. They came on our present boat from the factory; but if they hadn't, I would have installed them. I believe the days of straight gas filters are numbered because of the use of ethanol gasoline. The separator filters help keep the gas as clean and pure as possible. If you can get straight gas, without ethanol, then regular gas filters should be fine. Up here, in the northeast, only e10 fuel is available. Hy
 
The best thing you can do is upgrade to Racor filters, those will have a bowl with a drain which will allow you to monitor and drain of any water.

Cor
 
water separating filters are generally not used on gasoline engines. if there is enough water in the fuel it will shut down the engine but wont hurt the motor. diesel engines are water intolerant. there is no harm in using a water separating filter if you like as long as it does not negatively affect your fuel pressure on the suction side of the fuel pump. since ethanol scavenges water, it is likely not to be an issue unless you take on a load of bad fuel in which case the separating filter is not really going to do much.
 
This is going to be real news to Crusader Engine Co. :
Here is Crusader's bulletin regarding E10 fuels .
http://www.crusaderengines.com/NewFiles/CrusaderEthanolStatement.pdf

If you scroll down , you will see they strenuously recommend employing a good remote water-separating filter in the fuel supply to their gas engines.
And the on-engine filters they supply with the engines are water-separating type as well. I know very few boaters with gas engines that don't use w-s filters.

Are they even more important with compression-ignition diesels? I would think so.

quote:
Originally posted by vic33004

water separating filters are generally not used on gasoline engines.

Click to expand...
 
To Vic33004 water in gas not a problem? It very much is an issue!
Have you ever seen what kind of problems it can cause?
It will ruin fuel pumps and injectors in no time, it will gum up your carburetors and will cause intake valves to get stuck.
I have personally had all of this happen to boats I have owned over the years. One was a brand new boat with a 320hp Volvo penta
small block that within 10 hours broke down due to water in the fuel system. It was caused by a wrongly installed vent line, it allowed
water to enter the fuel tank.
The other was a carburetor 454 big block that had an intake valve that got stuck due to bad fuel caused by water contamination and it
blow a piston. It had running problems and the yard was working on it when they totally destroyed the piston, I bought the boat like this
and had to scrap the motor! Water had gotten into the fuel tank through bad deck fills.

Water in the fuel is bad news gas or diesel.

Cor
 
I know this is a dumb question, but until I get an answer I'm dumb for not asking! If ethanol in gas is such a problem with attracting water into the tank, how come vehicles don't have fuel/water separators?
 
Much smaller tanks and in cars you tend to run through a tank of gas in 3-8 days? A boat can sit for weeks / months with the same gas in it
 
Also land vehicles gas tanks are only vented through vapor recovery system that isolates it from moist ouside air, as opposed to boats' wave-battered vents that are most always only a couple feet from water at best .
Plus the fill caps on cars and trucks are rarely prone to water intrusion from rain, spray ,washdown through cracked or missing o-rings as is all too often the case on boats.

The filter attached to your in- tank car fuel pump may not be drainable, but do you know for sure it's not water-separating type to help avoid injector and other problems ?
 
So what have we determined here ? Are spin on, marine fuel filters adequate water separators or not ? Is the only REAL separator the kind with a drain on the bottom ? If water is so detrimental in gasoline engines with a carburetor why did they dribble water from a coke bottle down the throat while revving the motor to clean carbon deposits (recommended back in the day) with a benefit & no damage. Many of us have accidentally had water intrusion from different goof's when fueling. I left the cap off of my filler for months in winter 08. Mixed some fuel conditioner in a gallon can of gas and poured it into the tank, oops, forgot to replace the cap. I know some snow and rain found it's way into the system. Never had an issue. Only separator is my spin on type. I have gone thru thousands of gallons of gas in the last few years. Might be time for a new filter & a spare.

Water in diesel fuel ? Now there's a catastrophe waiting to happen. Compression is much higher, 14:1 - 18:1 and higher, compared to gas of about 10:1.
I might add that as far as I know there hasn't been any fuels with ethanol or methanol in my tanks. In fact around the lakes, gas stations advertise non alcohol fuels for a few cents more per gallon.
Speaking of fuels. It has been my experience that today's fuel's (of marginal quality) have a longer life before degrading, in the winter than in the summer. There's an experiment for somebody next summer. two quarts of the same gas, one in the refrigerator, one not. How long before separation ? OR , two quarts of gas, one stored with my favorite, SeaFoam and the other with Stabil. At the end of the summer are they both still good ? That's all I got. Carry on.
 
Vic, just curious, where did you get the information that fuel water seps aren't generally used on gas engines?
 
OK, so Crusader is strongly recommending a water separator type filter for their engines. My engine is a 454 carbureted Mercruiser with the usual gasoline type fuel filter. Question: can the same existing fuel filter housing be used with a simple replacement of the filter itself by a 10 micron water separator type filter? Is a new filter housing required? Does the new Mercruiser water separator filter housing have a petcock for draining water? Will other make filter housings fit 89876A3 base assembly mounting?
If a 10 micron water separator filter will fit the current base assembly it would sure simplify things.
I do know that filter housings with the clear plastic bowls to visually check for water are not approved for inboard engines.
 
We have had issues with water in both gas and diesel for years.
The main problem with water in ethanol blended fuels is that once the water reaches 0.5% water by volume the water starts to pull the ethanol out of the fuel. 0.5% is equal to 5/8 of an ounce of water in a gallon. Once this process begans (phase separation) a corrosive environment starts inside your fuel system.

The main problem with water in the engine is you can not compress water, therefore distorying your injectors.

Unrelated to water in gas, but related to fuel; recent reports we have received show that a corrosion has been found in ULSD tanks across the country linked to ethanol. Believed to have been co-mingled by both common piping systems and delivery trucks. This corrosion is found below the fuel (in the sludge/water) in the fuel and in the Ullage area (the air space abovevthe fuel).
 
quote:
Originally posted by bobalong

So what have we determined here ? Are spin on, marine fuel filters adequate water separators or not ? Is the only REAL separator the kind with a drain on the bottom ? If water is so detrimental in gasoline engines with a carburetor why did they dribble water from a coke bottle down the throat while revving the motor to clean carbon deposits (recommended back in the day) with a benefit & no damage. Many of us have accidentally had water intrusion from different goof's when fueling. I left the cap off of my filler for months in winter 08. Mixed some fuel conditioner in a gallon can of gas and poured it into the tank, oops, forgot to replace the cap. I know some snow and rain found it's way into the system. Never had an issue. Only separator is my spin on type. I have gone thru thousands of gallons of gas in the last few years. Might be time for a new filter & a spare.

Water in diesel fuel ? Now there's a catastrophe waiting to happen. Compression is much higher, 14:1 - 18:1 and higher, compared to gas of about 10:1.
I might add that as far as I know there hasn't been any fuels with ethanol or methanol in my tanks. In fact around the lakes, gas stations advertise non alcohol fuels for a few cents more per gallon.
Speaking of fuels. It has been my experience that today's fuel's (of marginal quality) have a longer life before degrading, in the winter than in the summer. There's an experiment for somebody next summer. two quarts of the same gas, one in the refrigerator, one not. How long before separation ? OR , two quarts of gas, one stored with my favorite, SeaFoam and the other with Stabil. At the end of the summer are they both still good ? That's all I got. Carry on.

Click to expand...


Ayuh,.... A canister type fuel filter, IS a water separating filter, by Design...

Fuel, whether gasoline, or diesel comes in at the top of the filter, 'n leaves the housing, again, at the top...
Water, falls to the bottom of the filter, because of gravity...
Water is Heavier than either fuel...

The petcock at the bottom of some filters, is to test for water, not so much to remove it...
If yer gettin' that much water, the element needs Changin', not just draining..
'n if ya look long enough, 'n hard enough, Yes, Wix builds filters, With drains, that fit the standard filter housings found on All of the typical motors we use, Merc, Volvo, OMC, Crusaders, etc...
But on most factory installations, there usually ain't room enough, below the filter canister...
You can also find various Sized filters to fit the standard housings,...
1 pint, to 1 quart..

Pouring water down through the carb's throat to de-carbonize the cylinders is Completely irrelevant to this discussion,...
The water goes directly to the combustion chambers, 'n nowhere near the fuel delivery system, other than straight through the carb's throat...

Water in the fuel, leads to detonation in gasoline motors, 'n to a lack of power in a diesel motors, because water displaces the fuel, 'n water don't burn...
Compression ratios are also irrelevant...

Water in the fuel, leads to corrosion in the fuel delivery system, which causes Way more problems than the water itself...
 
quote:
The main problem with water in the engine is you can not compress water, therefore distorying your injectors
Click to expand...

I doubt this. Most liquids are not very compressible but the key issue is that injectors are not designed to compress fuel, just the opposite. they rely on the lack of compressibility to deliver a precise amount of fuel in a fixed spray pattern when they "pop".

Water will allow corrosion and suddenly change to high temp and pressure steam in the injector tip and cylinder. That’s the cause of the amazing “steam cleaning” seen in water intrusion engine failures. Water also lack lubricity of fuel.
 
perhaps my intial post was not well worded. a typical gasoline fuel filter will trap water in the bottom of it and does effectively provide a barrier to injesting water into the fuel system if in small amounts in the fuel source.

diesel engines require a more robust filtration system that is generically refered to as a water separator/filter system. a few drops of water in a diesel injector and that is the end of the injector and possibly much more. A gas engine may also suffer damage if water is run thru the fuel system however generally they are more tolorant of it and thus dont normally have a water separator/filter system in addition or ILO the typcial fuel filter.

to the OP, before changing your filtration system it is wise to consult the engine mfg and see what specs on fuel flow and pressure drops are tolorated by your specific engine. as long as you meet the filtration requriement specifications you can change it all you like.
 
quote:
Originally posted by Bondo
Ayuh,.... A canister type fuel filter, IS a water separating filter, by Design...

Fuel, whether gasoline, or diesel comes in at the top of the filter, 'n leaves the housing, again, at the top...
Water, falls to the bottom of the filter, because of gravity...
Water is Heavier than either fuel...

The petcock at the bottom of some filters, is to test for water, not so much to remove it...
If yer gettin' that much water, the element needs Changin', not just draining..
'n if ya look long enough, 'n hard enough, Yes, Wix builds filters, With drains, that fit the standard filter housings found on All of the typical motors we use, Merc, Volvo, OMC, Crusaders, etc...
But on most factory installations, there usually ain't room enough, below the filter canister...
You can also find various Sized filters to fit the standard housings,...
1 pint, to 1 quart..

Pouring water down through the carb's throat to de-carbonize the cylinders is Completely irrelevant to this discussion,...
The water goes directly to the combustion chambers, 'n nowhere near the fuel delivery system, other than straight through the carb's throat...

Water in the fuel, leads to detonation in gasoline motors, 'n to a lack of power in a diesel motors, because water displaces the fuel, 'n water don't burn...
Compression ratios are also irrelevant...

Water in the fuel, leads to corrosion in the fuel delivery system, which causes Way more problems than the water itself...

Click to expand...


True that all but small in-line type filters will have some settling out for water and crud but on a true water separating filter the filter element itself will block almost all of the water from passing and it will drop into the bowl.

That said a lot of the spin on elements nowadays are water separating but not all.

To the OPs question water separaing filters are good. Specifics depend on your engines. There may well be a good spin on cartridge to replace your existing ones.

They do not however fix phase separation with ethynol fuel. Once that happens the fuel is trash.
 
OK, this is the skinny. On the Mercruiser engine (454 cu.in.) you can replace the existing filter bowl with 35-809100 which includes the new 10 micron filter element. It attaches to the "base assembly" into which the fuel hoses fit. This is a Racor filter which will handle 90 gal./min.
The filter bracket or "base assembly" is 89876A3.
The new bowl has a CG approved drain valve at the bottom. There is a bowl without a drain valve but I do not have the number. Am installing this week.
 
Every gas engine boat I have owned since the early 90's has had a water separating fuel filter on them.
Cheap, safe insurance.
 
quote:
Originally posted by Gregory S

Vic, just curious, where did you get the information that fuel water seps aren't generally used on gas engines?

Click to expand...


I would also like to hear the answer. Mine came from the factory with them. Should I tell Mercruiser that they dont need to install them?..
 
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