Gas filter/water seperator GPH?

[capslock118]

Hi There,

I have a 1990 (or so) 2-stroke mercury 135hp 6-cyl.

I do not have a water/fuel separator and I was thinking of installing one.

The list of Racor filters in the west marine catalog state flow rates, anywhere from 35gph to 90gph.

How can I determine what my flow requirement is?

 

[saumon]

Re: Gas filter/water seperator GPH?

As a rule of thumb, your consumption is roughly 1/10 of your hp at WOT. Your's should be 13.5 GPH at WOT so all the filters are ok and won't impede the fuel flow.

 

[capslock118]

Re: Gas filter/water seperator GPH?

Hi Saumon,

Thank you for that info.

As someone who is not very engine savvy, can you define WOT for me?

I see WOT in my seloc book but I cant define it.

 

[CLAYC]

Re: Gas filter/water seperator GPH?

Wide Open Throttle!

 

[capslock118]

Re: Gas filter/water seperator GPH?

Thanks clayc,


Now, being a 2-stroke engine with direct injected oil, installing this fuel filter should not cause any issues? I wouldn't guess so since the oil is sent to the engine in a completely different line.

thanks

 

[capslock118]

Re: Gas filter/water seperator GPH?

Actually,

A better question I have to ask.

The installation instructions do not make a distinction as to where the primer bulb goes for the fuel line.

Does the primer bulb typically go before or after the fuel filter? i.e. between the fuel tank and the filter or between the filter and the engine?

 

[Chris1956]

Re: Gas filter/water seperator GPH?

Primer bulb should be between Seperator and Motor. Use 3/8 ID fuel line and 3/8" ID brass fitings on the seperator.

 

[capslock118]

Re: Gas filter/water seperator GPH?

Use 3/8 ID fuel line and 3/8" ID brass fitings on the seperator.

I was wondering about that since I need to buy more hose to make this work. The outer shell of the hose came out to 5/8" so I wasnt sure.

thanks.

 

[sschefer]

Re: Gas filter/water seperator GPH?

I hgihly recommend that you use the Quicksilver 25 micron fuel/water separator that is designed and recommended by Merc for your engine. I've tried several of the other aftermarket models and have come to the conclusion that the Merc is perfectly adequate for protecting your engine.

You need to leave the filter that is inline on the motor. It will be your guard against dirt in your oil.

 

[capslock118]

Re: Gas filter/water seperator GPH?

I hgihly recommend that you use the Quicksilver 25 micron fuel/water separator that is designed and recommended by Merc for your engine.

mercury parts express sells racor products, doesn't that imply a blessing from them for use of these products? My engine is from 1990 and has never had a water/fuel filter.



also:

I have a sea ray which does not have much for space for 'stuff' in the back. I was planning on putting this filter in the underside where the bilge is (and where the fuel line starts). This particular filter for instance has some sort of see-through drain on its bowl assembly for water / debris to drain out. Is it safe to allow the filter to drain into the bilge? or is that now how this stuff works?

 

[sschefer]

Re: Gas filter/water seperator GPH?

mercury parts express sells racor products, doesn't that imply a blessing from them for use of these products? My engine is from 1990 and has never had a water/fuel filter.

I don't know what that implies. I know the Quicksilver line works and in my boat the Racor cavitated. The Quicksilver solved the problem and therefore is my recommendation.

I have a sea ray which does not have much for space for 'stuff' in the back. I was planning on putting this filter in the underside where the bilge is (and where the fuel line starts). This particular filter for instance has some sort of see-through drain on its bowl assembly for water / debris to drain out. Is it safe to allow the filter to drain into the bilge? or is that now how this stuff works?

NEVER DRAIN FUEL INTO THE BILGE INTENTIONALLY. A small spark can ignite fumes that are trapped in the bilge long after the spill has been cleaned up.

If you must place the filter in the bilge then you must also install a bilge blower system. I have one installed in my boat and I run it for at least 5 minutes before starting the engine. It's easy to install and a cheap investment that may save your life.

 

[capslock118]

Re: Gas filter/water seperator GPH?

Well sschefer,

I took your suggestion and I'm getting the mercury build filter and filter base from my dealer instead of the racor.

NEVER DRAIN FUEL INTO THE BILGE INTENTIONALLY. A small spark can ignite fumes that are trapped in the bilge long after the spill has been cleaned up.

Right, I agree completely which is why I chose not to use the racor brand, it looks to me like the filters without the bowl are self-contained, so I should be fine there.

Thanks for your help.

 

[sschefer]

Re: Gas filter/water seperator GPH?

Great, I think you'll like it.

 

[Chris1956]

Re: Gas filter/water seperator GPH?

Ok, What does cavitation have to do with a water seperator? I do not get the connection.

 

[capslock118]

Re: Gas filter/water seperator GPH?

oo, i'll take a guess chris before sschefer get's a chance to answer.

Google defines cavitation as:

the formation of vapour bubbles of a flowing liquid in a region where the pressure of the liquid falls below its vapor pressure. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation, and noninertial cavitation. ...

So, that said, perhaps he means that the vopour bubbles trapped inside the filter head and prevented or hindered fuel flow.