Thread: Fuel Filtration For Common Rail Diesels

Originally Posted by Dougal

So Ben. Was there any word on water causing injector failure as well? Where I'm going with this is do we need to install water traps and filters or is just an extra filter going to do the job?

I'm also interested in what the failure mode is. Is it accumulated particles blocking up fine ports, is it wear or is it something else?

It is wear due to the particles.

Water is a huge issue as well, however not dealt with in this study. Now that Euro fuels can have 10% bio for lubricity reasons, water removal from diesel is much harder. Additional water seperation wouldn't hurt - however most modern fuel filters are designed to do both. Sedimentation can't be relied on to remove water. Correctly designed filters will trap water droplets in the same way as solid particles (and drain them to the bottom).

Hope you dont mind me chiming in here Ben


We are now running a 2 micron secondary filtration on all our CRD's. Most CRD injectors will only pass up to 3 micron particles.

As mentioned the injectors are often a disposable item. It is a common practice to fit 2u filters when running higher than standard fuel pressure as injector tops have been known to split when ingreased with crud less then 10u. ( Some of our chipped CRD systems run in excess of 30000psi at peak duty.)

I use both Parker Racor 230R30 G-force filter with the R20S 2um filter and Baldwin DAHL 65 series with a 66 2um replaceable cartridge.

Some vehicle's will sense the restriction and bring up fault codes as a result of a secondary filtration. To fix this issue, I have fitted a facet electric pump near the tank.

Cheers Tony

Wile on the topic of extra filtration on our diesels.
I have had more drama's then what's its worth fitting filter/water traps away from the engine bay due to our diesel waxing (normal) at -5 and not reverting back to liquid (Needs to be 28deg)
Diesel will still flow to some extent as wax breaks up to allow liquid flow till system warms up.(28 and over)
With remote filter locations the wax can continue to build up unless the fuel is warm enough from the tank and return line to beat it.

Also on 2um filtration, it has to go cr pump side of the factory filtration so factory removes the large bones first. Other way around is hopeless.

AUX Filter placement can bring up some questions with manufactures warranty!

The racor system is regarded as a safer option being spin on. (Less risk of contamination during servicing. (Just expensive)

T

So If I may,

For those like me who aren't technical what is the solution for a 2001 TD5 defender if you wish better fuel filtration.

Originally Posted by Rangier Rover

We are now running a 2 micron secondary filtration on all our CRD's. Most CRD injectors will only pass up to 3 micron particles.

Agree with all the rest Tony - thanks for your input.

However - one thing I feel the need to correct... Filters aren't sieves, so micron ratings are really a load of BS. Your 2 micron filter will still be letting particles as large as 10 microns get through. Under LAB conditions!

The main point of the research I posted at the start was that a filter that captures 50% of 2 micron particles under lab/ISO tests, may only capture 25% in a real world situation.

This is from the air filter tests, but fuel filters work in exactly the same way...

In fact it is much easier to collect particles in air because the viscosity is lower so particle inertia is more significant.

Also - a filter that removes 50% of 2 micron particles on a 6L diesel may only remove 10% when fitted to a 3L diesel. Micron ratings are the biggest load of BS in the industry, but they perpetuate because customers like them (and many filter "manufacturers" are really just filter "rebadgers" and "resellers" - so they don't understand how filters work either )

Originally Posted by scott oz

So If I may,

For those like me who aren't technical what is the solution for a 2001 TD5 defender if you wish better fuel filtration.

The bottom line is installing a 2nd fuel filter is a very good idea. Whether that is a course rock catcher prior to the main filter (between tank and existing filter) or a finer filter like Rangierrover mentions fitted after the main filter (between existing filter and tank).

CR diesels have a high fuel flow, so you need to get a filter assembly designed for sufficiently high flow (but not too large as it won't filter as well). The size of the fittings is a good indicator.

I have seen that some fuel filters are rated at a certain flow rate and others are said to suit a certain hp diesel. Is the hp rating likely to be for NA diesel or turbo CR. The reason I ask is because I assume that the CR systems will have a higher flow rate as they flow a fair bit of fuel back to the tank. If so then the hp rating may not be a good indicator of fuel flow! Is this reasonable?

Originally Posted by slug_burner

I have seen that some fuel filters are rated at a certain flow rate and others are said to suit a certain hp diesel. Is the hp rating likely to be for NA diesel or turbo CR. The reason I ask is because I assume that the CR systems will have a higher flow rate as they flow a fair bit of fuel back to the tank. If so then the hp rating may not be a good indicator of fuel flow! Is this reasonable?

That is more or less correct. Filter efficiency (effectiveness of particle capture) is strongly dependant on flow rate. The horse power ratings are a rough equivalent - used since most people don't know their fuel flow rate.

This of course goes out the window for CR diesels as they recirculate much more fuel.

OK,

So for my TD5 is there a setup available that will give me better fuel filtration?