Fuel filters Rotax 912

[Bush-pilot]

Good day all, I recently had an incident which resulted in an engine out on a Rotax 912. The cause was a possible blockage on one of the in-line filters feeding the left-hand carb.

 

Can anyone give me good advice on good quality gauze type filters to use? Seems the local AMO used the normal automotive type plastic filter (paper elements) which might have proved to be faulty. I fly an average of 80 hours per month and need the most reliable filter system available. Fuel is filtered through a Racor system when re-fueling. Look forward to hearing from you folks.

 

 

[SDQDI]

I have changed from using clear glass filters to using a largish automotive filter. I will take some pictures today and post them.

 

 

[SDQDI]

So originally I just ran three of these glass filters, one from each wing tank and one after the header tank

 

 

They worked well BUT Ole had heard of one that failed and dumped the full tank of fuel while sitting in a hangar, he was a tad sceptical about this and my hornet was over at Taree for a service and as luck would have it one of mine failed while there so we changed the two that come down from the wing tanks to these

 

These can't fall to bits and have plenty of capacity. Not being see through I change these at every oil change.

 

We kept the one glass filter after the header tank BUT Ole machined up a new solid through rod which hasn't had any issues.

 

 

[fly_tornado]

This is what 20 years of premix from steel fuel cans leaves behind

 

 

[Blueadventures]

So originally I just ran three of these glass filters' date=' one from each wing tank and one after the header tank[ATTACH=full']54354[/ATTACH]They worked well BUT Ole had heard of one that failed and dumped the full tank of fuel while sitting in a hangar, he was a tad sceptical about this and my hornet was over at Taree for a service and as luck would have it one of mine failed while there so we changed the two that come down from the wing tanks to these [ATTACH=full]54355[/ATTACH]

 

These can't fall to bits and have plenty of capacity. Not being see through I change these at every oil change.

 

We kept the one glass filter after the header tank BUT Ole machined up a new solid through rod which hasn't had any issues.

Hi agree re the glass ones. I still have two glass ones fitted. You must purchase good quality ones as I found the first ones I bought needed to be tighten hard to stop a leak. Closer inspection found the end caps threads were not tapped square to the end cap which resulted in the glass being an out of a square fit and this is why it had to be tightened heaps to pull the glass into the gasket and stop the leak. The new ones I bought are well made and a correct square on fit. I do find if the the filters get dry, on fuel in them, stay over a month they need retightening to seal. Best to keep them wet; full of fuel. My DI is to lightly grip the glass between thumb and finger and try and turn; then turn on fuel taps; and look for any leak. This works well. Cheers

 

 

[danny_galaga]

I’m confused about why this should be an issue. Even a plastic Ryco job on my beach buggie lasted until it was full. Why are aircraftfilters less reliable than car filters?

 

 

[Sav 4352]

I've been using Ryco Z14 since 2004 without any problems, change every 25 hours.

 

 

[Bush-pilot]

Thanks for the feedback everyone. Maybe the key is to change regularly. Every 25 hours makes sense.

 

 

[Malindi]

This is the type of fuel filter recommended in the U.K. It’s a plastic gauze that doesn’t clog up in the same way as paper ones and you can see if there is any slime on it or sediment in it. I don’t know where you can get them in South Africa though I have read somewhere that there is one available and recommended in S.A. that is made by Mercedes. Personally I wouldn’t want one you can’t see the actual filter gauze on daily inspection. I also wouldn’t want to change it out every 25 hours especially if I were flying the 80 hours per month your flying. That’s a new filter almost every week. If you’ve got someone coming from the U.K. you could get a bunch of these from skydrive.co.uk. That’s what I do (to Kenya).

 

 

 

[SSCBD]

Have used one of these types or larger glass ones for many many years as last filter to engine and have found them brilliant. As you are flying a lot of hours per month bush flying? Fuel can be a bit of a problem. It shows up any water in the system that wing draining misses and visual of the fuel as well. Easy to remove and clean. Saved a lot of problems over the years.

 

 

[jabarte]

just a comment on hose clamps.

 

excess tail protrusion rubbing on adjacent hoses or components can make a hole very quickly, especially where abrasive dust etc is involved.

 

The photo of the glass filter at the top of this thread is an example of such potential.

 

 

[dale boyd]

the good glass filters have usa cast on them ,if it doesn't have that on them they are chinese copies and the threads aren't ever done propely .seen them come apart on older carburettor engine cars.the filtering inside is also small and block reasonably easily

 

 

[Ian West]

Good day all, I recently had an incident which resulted in an engine out on a Rotax 912. The cause was a possible blockage on one of the in-line filters feeding the left-hand carb.Can anyone give me good advice on good quality gauze type filters to use? Seems the local AMO used the normal automotive type plastic filter (paper elements) which might have proved to be faulty. I fly an average of 80 hours per month and need the most reliable filter system available. Fuel is filtered through a Racor system when re-fueling. Look forward to hearing from you folks.

Hi Bush PioletAn inline glass filter that allows sediment and water to settle out and can be easily taken off and emptied out if necessary are the best. These of course must be located in an easily assessable place.

 

The real issue is the quality of fuel being put in the tank.

 

I have two plastic Gerry can containers that are not used for any other purpose - all fuel from these go through a Mister Funnel which removes all sediment and water - this allows for clean fuel going into the tank.

 

If purchasing a second hand aircraft my first job would be to drain and clean the fuel tank or tanks, change fuel filters and start the a fuel practise similar to what's stated above.

 

Good flying

 

Westy-3261

 

 

[skippydiesel]

Check out:

 

My fuel filters are Hengst H 102 WK (for those who might want an inbuilt elbow, try H 103 WK)

 

 

Readily available, reputable manufacturer, gauze filter, lightweight, no leaks, cheap, proven, visual inspection, can be cleaned (but why would you), used by my aircraft manufacturer & Mercedesies diesel cars/light commercials.

 

 

[skippydiesel]

I forgot to mention -

 

• I am pretty sure the gauze is metal (not plastic as suggested by Malindi) not that this matters as it "does the job".
   
   
   
  
• I have always used high pressure fuel injection(FI) line hose clamps. FI clamps are designed to give even clamping pressure around the hose, will not dig into the hose and can of course be re used indefinitely.
   
   
   
  
• I filter ALL my fuel INTO the aircraft using a funnel fitted with a special fabric fuel filter (a bit similar to a Mr Funnel, which does not suit my aircraft). Consequently I do not get much in the way of contaminants in my filters or when I do my preflight fuel check.
   
   
   
  
• I keep my fuel in air tight, designated plastic "jerry" cans - again minimising contamination.
   
   
   
  
• Many LS aircraft manufacturers specifically warn AGAINST paper type fuel filters - dont know why but may relate to quality control (many generic filters that look similar to reputable brands in the marketplace).
   
   
   
  
• Apologies for poor quality of photos in previous post.
   
   
   
  
• All the specs on the Hengst filters are available online
   
   
   
  

 

 

 

 

[Downunder]

• Many LS aircraft manufacturers specifically warn AGAINST paper type fuel filters - dont know why but may relate to quality control (many generic filters that look similar to reputable brands in the marketplace).
   
   
   
  

Plain Paper element filters used to "swell" and block with water or other chemical contaminants.These days most paper filters are treated with a coating to prevent this....The secret is knowing which are coated and which not, I guess.....

 

 

[Malindi]

Skippydiesel, yep they’re the ones. Do you know where to get them in Aus? I also use the same measures to minimalize the risks of filling with dirty fuel and I haven’t seen any sediment in my filter in quite a while.

 

 

[skippydiesel]

Skippydiesel, yep they’re the ones. Do you know where to get them in Aus? I also use the same measures to minimalize the risks of filling with dirty fuel and I haven’t seen any sediment in my filter in quite a while.

I have a small supply (purchased a bulk amount several years ago) so could help you out.

Mercedes parts will supply, at a cost.

 

OR

 

Mercedes aftermarket supplier like:

 

M.B Spares & Service

 

14/16 Lyell St. ACT

 

(02) 6239 1099

 

Otherwise try googling Hengst Filter suppliers in your state.

 

Make sure you ask for the transparent filters - many of the same spec non Hengst filters are now opaque

 

 

[Bush-pilot]

This is the type of fuel filter recommended in the U.K. It’s a plastic gauze that doesn’t clog up in the same way as paper ones and you can see if there is any slime on it or sediment in it. I don’t know where you can get them in South Africa though I have read somewhere that there is one available and recommended in S.A. that is made by Mercedes. Personally I wouldn’t want one you can’t see the actual filter gauze on daily inspection. I also wouldn’t want to change it out every 25 hours especially if I were flying the 80 hours per month your flying. That’s a new filter almost every week. If you’ve got someone coming from the U.K. you could get a bunch of these from skydrive.co.uk. That’s what I do (to Kenya).

Many thanks for this. This the exact filter that I have been looking for, Regards

[Bush-pilot]

M

 

Have used one of these types or larger glass ones[ATTACH=full]54387[/ATTACH] for many many years as last filter to engine and have found them brilliant. As you are flying a lot of hours per month bush flying? Fuel can be a bit of a problem. It shows up any water in the system that wing draining misses and visual of the fuel as well. Easy to remove and clean. Saved a lot of problems over the years.

Many thanks for this! much appreciated!

[Blueadventures]

Good day all, I recently had an incident which resulted in an engine out on a Rotax 912. The cause was a possible blockage on one of the in-line filters feeding the left-hand carb.Can anyone give me good advice on good quality gauze type filters to use? Seems the local AMO used the normal automotive type plastic filter (paper elements) which might have proved to be faulty. I fly an average of 80 hours per month and need the most reliable filter system available. Fuel is filtered through a Racor system when re-fueling. Look forward to hearing from you folks.

Try 'Flylight' in UK they have these for 3.32 pound. Link - Fuel System I get bits to Australia very fast and easy to deal with.

Cheers

 

 

[Bush-pilot]

Try 'Flylight' in UK they have these for 3.32 pound. Link - Fuel System I get bits to Australia very fast and easy to deal with.Cheers

Thanks! will do!

[skippydiesel]

Try 'Flylight' in UK they have these for 3.32 pound. Link - Fuel System I get bits to Australia very fast and easy to deal with.Cheers

Looks like a Hengst H102WK, at a fair price (in the UK) BUT then there is the dreaded delivery cost - is there no Hengst Filter supplier in South Africa ? If there is, you should be able to get them at much the same cost or less (without added delivery).

 

 

[Bush-pilot]

Looks like a Hengst H102WK, at a fair price (in the UK) BUT then there is the dreaded delivery cost - is there no Hengst Filter supplier in South Africa ? If there is, you should be able to get them at much the same cost or less (without added delivery).

Thanks, will try them, seems there is an agent in Johannesburg.

[Malindi]

Did a bit of web snooping for you and found a website that sells them in South Africa. cometaviation.co.za Phone 011 8250048 (Germiston). ZAR 105 (about us$9.00) so quite a mark up but hey, they deliver. They also stock Mr Funnel.