Fuel filter installation

[Bowser]

I am installing an in line fuel filter and am not sure which side to place the primer bulb. Is it between the tank and the filter or the filter and the motor?

[Noelm]

I like between motor and filter, close to Motor (within reason)

[Marky Mark]

Yep me too, nice and close to motor for me!

[Spaniard_King]

Why would you want to suck fuel through the filter,it's way more easy to pump it through :P

I install them and I always try to put the primer between the tank and the filter.

[dnej]

Garry,
I am with you, a pusher,not a sucker.That was the way I was told to set it up.
David

[FNQCairns]

I have a pusher and a puller, the pusher means I don't have to lean over the transom to prime it all the time as the filter is outside. Strictly speaking pushing through a filter that is designed to migrate and trap water overwhelms it so that while pumping through no water is caught.

cheers fnq

[Spaniard_King]

I have a pusher and a puller, the pusher means I don't have to lean over the transom to prime it all the time as the filter is outside. Strictly speaking pushing through a filter that is designed to migrate and trap water overwhelms it so that while pumping through no water is caught.

cheers fnq


I beg to differ.. most racors are rated to handle 90GPH go try to pump 90GPH with a primer bulb.. not to easy!!

[FNQCairns]

True rating Gary, but it applies to pressure drop not water capture, water is trapped in media through migration, this takes time and therefore low flow rates. To capture any water above what constitutes a false sense of security by media needs 2 micron and filters near capable of scrubbing the fuel. The spin ons at anything past virtually idle will only capture what wouldn't hurt/stop it anyway.

Other filtermakers who have solid industry reputations outside of the leisure market like the Cav/Donaldson/fleetguard have a specified low flow rate for a reason, Racor quietly lets it fly straight over everyones head.

cheers fnq

[Spaniard_King]

True rating Gary, but it applies to pressure drop not water capture, water is trapped in media through migration, this takes time and therefore low flow rates. To capture any water above what constitutes a false sense of security by media needs 2 micron and filters near capable of scrubbing the fuel. The spin ons at anything past virtually idle will only capture what wouldn't hurt/stop it anyway.

Other filtermakers who have solid industry reputations outside of the leisure market like the Cav/Donaldson/fleetguard have a specified low flow rate for a reason, Racor quietly lets it fly straight over everyones head.

cheers fnq

fnq, I honestly think what you wrote is a lot of cods wallop. If it were true a lot of injected engines would be suffering as they don't like any water

[FNQCairns]

Not cods wallop Gary just basic filter mechanics, it's like everything sales pitch, they are targeting the leisure market (glossy brochures with specs shy on standardised detail) 90gph and captures water above a minor % age would require a unit 5 times the physical media size and finer and multiple passes and somewhere decent for the water to stand until drained evaporated....just like the units built for boats that do polish the tanks contents through multiple passes hopefully before getting to the engine....there is science not marketing. The Racor at say 40% flow will do no better than the glass bowl water trap on a 70 year old massy Ferguson tractor L for L, units with real ratings as i mentioned above will migrate water at their rated flow.

Obviously injected engines do handle more water than some give them credit for because the racor is relatively hopeless at capturing water with it's high flow and large micron.

cheers fnq

[black runner]

The spin ons at anything past virtually idle will only capture what wouldn't hurt/stop it anyway.
cheers fnq

Have always had the bulb before the water separator/fuel filter.

See link below for water separating fuel filter test. I think the Quicksilver spin on I use is capable of separating water from fuel feed to my Yammie 60 at 10litres/hour FNQ. I will however install a bowl type to see evidence of water contamination.

http://continuouswave.com/whaler/reference/fuelFilter.pdf

Cheers

[FNQCairns]

Have always had the bulb before the water separator/fuel filter.

See link below for water separating fuel filter test. I think the Quicksilver spin on I use is capable of separating water from fuel feed to my Yammie 60 at 10litres/hour FNQ. I will however install a bowl type to see evidence of water contamination.

http://continuouswave.com/whaler/reference/fuelFilter.pdf

Cheers

That's nice, everything relates back to the flow rate because unless it is simply a water trap it must migrate water that's the mechanism, purely physical in nature, for this mechanism to work it needs low flow or very large media surface areas which in it's self amounts to emulating low flow. leisure marketed spin on's/ cav's etc do not have this...
Well company with a solid reputation commercially do ie Donaldson/cav etc as per I wrote above.

Back to the original point.......... I just then pumped my primer bulb to clear my tank of left over fuel from yesterday the LMF fuel meter was showing 160L/h maintained without drama.......IF THE PRIMER BULB IS BEFORE THE FILTER A PERSON IS FORCING 160L/H THROUGH THE FILTER MANUALY......no chance of migration of water to be trapped at those volumes.....yamaha, holden, ford, cav, ryco, merc, Racor, it's simply just not going to happen unless all the above I have already mentioned a couple time becomes true....large media area or low volume etc..... cannot simply go changeing the laws of physics to suit marketing or brand allegiances.

cheers fnq

[PWCDad]

Doesnt it depend if the water is in suspension or not? If the water is in suspension i.e. its been agitated via pumping the fuel is cloudy with water suspended in it.

That will pass the filter if water particles suspended are below its rated micron size?

If the water is "frank" water as in you pour a litre of water into a fuel tank it would NOT pass the racor type with fuel sight glass?

I worked for many years as a pumpman and gauger at an oil refinery receiving depot. The fuels were always coming from refinery with suspended water because we put a "slug" of water between fuels to separate them. For example diesel from petrols.

The pumps were filling the 6 million litre tanks at 250,000 litres per hour through 14 inch pipes so water got "very suspended". This was left to settle out for a few days and the water drained off via bottom of tank valves. In most instances it was 2 ft deep in the tank. Fuel was drawn from floating valves at the surface of the fuel.

Rarely would we have suspended water in our boat tanks, surely? It would be more frank water that the racor "would" handle?

Also .. isnt the filter media coated in a special chemical that lets fuel pass but not water particles because of differing surface tensions? Called coalescing from memory???

If my racor system is not up to the job I'll give it the flick and search for better ???

regards
Anthony

[black runner]

That's nice, everything relates back to the flow rate because unless it is simply a water trap it must migrate water that's the mechanism, purely physical in nature, for this mechanism to work it needs low flow or very large media surface areas which in it's self amounts to emulating low flow. leisure marketed spin on's/ cav's etc do not have this...
Well company with a solid reputation commercially do ie Donaldson/cav etc as per I wrote above.

Back to the original point.......... I just then pumped my primer bulb to clear my tank of left over fuel from yesterday the LMF fuel meter was showing 160L/h maintained without drama.......IF THE PRIMER BULB IS BEFORE THE FILTER A PERSON IS FORCING 160L/H THROUGH THE FILTER MANUALY......no chance of migration of water to be trapped at those volumes.....yamaha, holden, ford, cav, ryco, merc, Racor, it's simply just not going to happen unless all the above I have already mentioned a couple time becomes true....large media area or low volume etc..... cannot simply go changeing the laws of physics to suit marketing or brand allegiances.

cheers fnq

So at normal flow rates generated by a running outboard, a properly sized standard spin on/bowl type water separator fuel filter should do it's job.

However, if you pump a primer bulb, which is in-line on the inflow side of one of these filter types any water wll be forced through the filter element and out through the outflow side due excessive flow rates. Makes sense to me.

I will squeeze my bulb very carefully in future;D ......... or move it to the other side!

Cheers

[FNQCairns]

So at normal flow rates generated by a running outboard, a properly sized standard spin on/bowl type water separator fuel filter should do it's job.

However, if you pump a primer bulb, which is in-line on the inflow side of one of these filter types any water wll be forced through the filter element and out through the outflow side due excessive flow rates. Makes sense to me.

I will squeeze my bulb very carefully in future;D ......... or move it to the other side!

Cheers

Yeah that's pretty much it, there are all different sorts of outboards matched all different filter products. When relating the equation to the flow figures of those marketed at the leisure crowd at least halve the claimed flow rate as the flow rate spec in the instance of these company's will relate to pressure drop only not it's water capturing ability.

Of the top of my head the Cav/delphi filters have a manufacturer specified 40L/h flow rate...I have pushed many times more than that through them so they do flow heaps more yet this is a very low rate rate by leisure company marketed filter standards:).

So depending on the amount of fuel the engine draws and the micron and surface area of the filter media it's a matter of do you feel lucky punk dealing with a company that has no solid commercial industry reputation to protect when you read it's specifications.

So yeah as I said in my first post "strictly speaking"....


cheers fnq

[Scott nthQld]

I put mine in before the primer bulb. Why? because that's the way the boat was set up from factory, and where the filter is, having a primer bulb before the filter will just be a pain in the arse to be honest.

[eugah]

Mine is set up with the primer before the filter, however the only time i use it is to pump a bit of fuel through when i drain the filter.


Adrian