River City 4WD Club - Brisbane

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Hi guys at our last club meeting we were discussing fuel filters and Victor was promoting a 30 micron filter that would stop water getting through to your injectors

I have done a little research by contacting ebay sellers for there technical uses and advice

They come in microns from 2, 5 and 30 filters

the 30 micron is used as a pre filter to stop most of the contaminants before your standard filter

the 2 micron filter is used as a primary replacement filter before the injectors

One of the replies stated that no matter what filter you get it will not stop water getting into your injectors if the filters get full of water

a warning system will allow you to stop and drain before this happens
our standard filters usually has this already, but again some don't so check your current status

Search for this on Ebay and you can get them for $125 with no fittings or $170 with fitting best price so far
and you can also ask for a lower micron filter too

42093 Fuel Manager Filter Head 30 Micron Pre Filter
I fitted the fuel manager with the 30 micron filter to my 105 series last October after picking up water in vic high country, its fitted as a prefilter before the main filter,If your handy best to just buy the housing and element and make your own bracket . I also fitted the water sensor alert module and pump primer to it a month ago. Basicly a light or alarm comes on if any water is detected .When you first switch your key on an optional red led dash light comes on for 5 sec to confirm all is working so an alarm will pee you off . last weekend i fitted a same kit to my mates BT50 . On a trip late last year in the vic high country we both got water in our fuel at a servo . My direct injection motor just missed a bit untill i drained the filter but the common rail BT50 new with 40,000 km on speedo had to be freighted to Melbourne for major damage repairs to the pump and injectors and the cost was just over $13,000 not covered by warranty,
I got this information from Berrima Diesel on their filtration strategy Big Grin


It gives a good account of how pre filters work and why and some of their limitations
you will find also some news on how your main filter works there too

Pre-Filter systems: For Common Rail Diesels

A Pre-filter should be there to do exactly what its name says. Filter the fuel ‘pre’ the main filter. Why? If the fuel is in a poor state (contaminated with gunk/algae and other matter) it will have some of that removed so that the MAIN filter is left to worry about filtering the remaining stuff.

Our Pre-filter kits come with a 30 micron rated filter element. Why? To answer this we must first understand what the main filter is doing. Common Rail Diesels run 2 micron fuel filters. The 30 micron Pre-filter is 15 times more coarse than that. In other words the main Original filter is designed to catch the mosquitos while a Pre-filter will catch the rocks and rabbits and anything larger.

Q. Will the Pre-filter restrict the fuel flow?
Ans. No, the only time this might happen is if and when the filter becomes blocked. Most modern Diesel filter systems come with flow restriction indicators that would alert you if the fuel flow was restricted. On average we would expect the Pre-filter to be changed every 30,000-40,000km.

We recommend the main filter be still changed every 10,000km.

Q. Why is fuel flow so important.
Ans. Looking under a current common rail Landcruiser, for example, you will find a fuel cooler on the return fuel line. This is installed to help cool the fuel returning back to the tank after it has been through enormous pressure during its travels through the common rail fuel system. Some fuel return rates can exceed 8 litres returned for every 1 litre used to run the engine.

By installing a Pre-filter system you assure the Original filter system, with its alert systems for water contamination and fuel restriction, operates unhindered.

Water in Fuel and Algae:- Diesel and water separate very easily. If you have ever heard of ‘algae’ growing in Diesel fuel its actually growing in the water. When you have algae you have a large problem of a growing mass of blobs that can cover sensors and make them inoperable. Installing a water sensor alone will not guarantee protection from water contamination. Pre-filtering the fuel removes all these large messy bits and pieces so that ‘treated/filtered’ fuel is allowed to flow on to the main filter where its sensors and alarms can operate more successfully.

Good filtration starts before you stop to fill up. Buy fuel from a known brand station, try and stick with one brand as much as possible, keep your receipts. Comment(is this for Insurance purposes? anyone know?)

NO FILTER will stop what we call ‘Adulterated Diesel’. That is Diesel mixed with a clean concoction of other liquids that burn like kerosene, paint thinners etc. In other words a filter cannot separate ‘Coca Cola from Sprite’. Be wary of unbranded fuel stations.

We have seen a growing availability of additional Diesel filter systems and some of them are installed just plain wrong.
We have seen quite a few similar looking systems to ours come through the workshop with the Pre-filter installed ‘after’ the main filter.
Worse still the filter element being used has varied from a 5 to a 2 micron filter element.
In particular, installing a larger micron element after the Original 2 micron is useless.
Pre-filters are just that and should be installed before the Original main filter and with a Pre-filter sized filter element.

Our 30 Micron Pre-filter kits come with all the necessary items to install it:- fitting instructions, ‘heavy duty’ stainless steel fitting bracket, hoses, fuel line fittings, the filter system, a glass bowl for fuel inspection and a spare 30 micron filter.

These are installed BEFORE the main filter on ALL applications.
Our system can be retrofitted with an additional water alert system. This system come with the necessary installation info and uses a buzzer to alert you to water.

Les: Cool - check out the ebay site in my first post for good bargains on prefilters
I have been told the water sensor will cost at least another $200 if you need one