skippydiesel

I use:

Hengst In Line Gauze Fuel Filters

Part No - H103 WK (90 degree fitting one end)

Part No - H102WK ( straight)

Both filters have:

8mm inlet/outlet spigots

An overall width of just 36mm

Overall length of 103 mm

Hengt claim a fuel filtration capacity of ≥ 2 µm (0.002 mm)

I have found these filters to have the following excellent features:

Clear body - for easy condition check

Very strong - in normal use it is just about impossible to break these beauties

Light weight - why add grams when you don't need to.

Leak free - unless damaged somehow, the fully sealed body cannot leak. I use good quality fuel injection hose clamps to ensure the push into hose fit does not leak or pull out.

Large Filter Area - very low fuel flow restriction/ less stress on pumps/ less likely your engine will experience total fuel starvation should contaminated fuel be inadvertently introduced to your system.

Long service life - assuming you are only using clean fuel in the first instance, these filter need only be replaced "on condition" however I would be inclined to replace them when you replace your fuel hoses.

Reusable - for the most part, with care & a little air pressure, most contamination of the filter can be removed. Why bother, they are so cheap, just replace them.

Cheap - I always carry spares in the unlikely event that I need to do a "field" replacement.

German Designed - made in Israel these filters are beautifully engineered and presented.

To be doubly sure that I am using clean fuel - I have a generic paper filter on my drum delivery pump and I use a filter funnel as well. I also carry a filter funnel in my aircraft the event of needing fuel away from home.

If you cant find any HENGST filters, I carry a small supply and may be able to help. S

I didn't think they made the black one anymore? I thought the red bottle (with the same name as the old black) replaced the black bottle.

With regard to the formulation (Red/Black Bottle), I only have B Flood (BF) technical advisers comment that there has been a change.

It would not be the first time there has been a packaging change for an identical product, however I am inclined to go with the BF advice on the matter.

I have never used "the goo".

After reading most (skipped much of the agronomy) of the proceeding comments, it would seem to me that "the goo" has some benefit, when used sparingly.

The temptation to use a lot of goo (more is better/not!) should be avoided as it does not improve the automatic sealing of holes and may lead to an imbalance of the wheel.

I would have expected the "goo" supplier to provide instructions to guide the user - perhaps CTFarmer actually read the instructions (not a real man) from which he derived the recommendation of 100 mm/tyre.

Further it would seem that the only negative to using the "goo" is that it makes tube repairs difficult/impossible. I assume even" the goo" will sometimes fail. Perhaps the solution here is to carry a spare tube or two.

Was there a recommendation for the best brand of "the goo" berried somewhere in the proceeding conversation??

My aircraft is rarely exposed to the various thorny hazards listed but I have taken the precaution of using hopefully the strongest, suitable, tyres I could find 8 ply "Deli Tire" on the mains & 6ply "Mitas Aero" on the nose.

Good new from B Flood (BF) - they do not think there is anything significant in the small oil pressures drop I have noticed in my 912 since its recent 700 hr service.

BF have suggested that I check the actual oil pressure using a master (calibrate) oil pressure gauge. This I will try and arrange at the earliest opportunity.

BF mentioned several possibilities that may have caused or contributed to the small pressure drop -

• ".........gauge starting to get tired, same with the oil pressure sender".
   
   
  
• ".........Aeroshell Sport plus 4 in the Black bottle, the new Aeroshell in the Red bottle is a slightly different formula.....". which could cause or contribute to a small pressure drop
   
   
  
• " ........spring in the oil pressure relief valve wears and this causes the oil pressure to drop".
   
   
  

I also queried the possibility of a defective oil filter as raised earlier in this conversation. BF's response was -

• "We have never come across a defective oil filter".
   
   
  

My thanks to the excellent service from the BF technical staffer who responded to my enquiry.

My change from AeroShell Sport PLUS 4 Black bottle to Red bottle ties in very neatly with the observations made by BF

All food for thought and action where appropriate.

With a little persistence you should be able to find an 8 ply or better, tyre to suit your application. I had good service from Kenda 8 ply tyres (wheelbarrow size, but ratted for road speeds & loads). Now have an Indonesian tyre similar to the Kenda but with higher road speed (forget the name, will have to get back to you if you are interested).

I bought an el cheapo twin carburetor pneumatic/vacuum balancer from a motor bike shop in Liverpool (NSW).

Consists of two Borden tube type vacuum gauges mounted on a panel. Pointers can be adjusted/zeroed, using a small flat screw driver. Also supplied with in line adjustable pulse restriction/damping taps. Only modification I have made was to purchase sufficient vacuum tube to enable me to sit in cockpit & read gauges, as I manipulate the engine rpm. Simple safe & easy to use. Works very well

Conversation is straying a bit - no matter - I have always been told that all but calibrated master gauges, are suspect. Further they should only be used to determine whats is a "normal reading" for that engine & gauge combination. For example:

Rotax specify a hot engine oil pressure normal range between 22(1.5 bar) - 73 psi (5.0 bar) @ 3500 rpm.

When I first acquired my aircraft, about 7 years and 300 plus hours ago, I was concerned by the apparent low oil pressure reading of 30 psi on my Speco (cheap) gauge at between 3000 - 5000 rpm.

I contacted B Flood (BF) - they reassured me that all was normal & within acceptable limits.

Without a calibrated oil pressure gauge to check the actual pressure at various rpm, I accepted the BF reassurance and have monitored my, as is, cheapo, oil pressure gauge aver since.

All was well (no deviation from the indicated 30 psi) in the intervening years and hours of flight until after the last oil change.

I noticed a very slight, 1-2 psi, drop in operating pressure (This is a small faced/scale/electrical gauge with increments of 10 psi). Still within Rotax limits, a very small change, on an inaccurate gauge, but I have been trained to view any deviation from "normal" with suspicion.

This is the value of your typical engine gauge - giving an indication of a deviation from what constitutes normal for that gauge/engine combination - not an absolute accurate reading.

No offence intended Geoff, unless you have your undoubtedly more accurate, small increment, larger faced, capillary tube, gauge regularly calibrate (Borden tubes and multiplier mechanisms ware) is unlikely to give much more usable information than my el cheapo.

HOT NEWS - BF have just got back to me with some thoughts on my oil pressure changes. The conversation continues but the stand out idea at the moment is the change from AeroShell Oil PLUS 4 (Black Bottle) to AeroShell Oil PLUS 4 (Red Bottle). Apparently the formulation has changed and this may cause a small drop in indicated oil pressure.

IBob - I stray badly and am probably far to late but I had good results with the Stewart (water born) paint system - not much chance of the fumes getting to you.

You are correct the subject has migrated somewhat but all comments still relate in some way to anomalous oil pressure readings - so probably all valid.

Have written to Floods - will pass on any pertinent comments from the oracle

My apologies, it was Scott, not John, who put forward the oil filter idea. Anyhow - in my long life, playing with all sorts of machines/equipment I have come to the conclusion that we humans are most often attracted to the complex/costly solution to any given problem. We should (but usually don't) adhere to the KISS principal and start any diagnostic effort with the simplest (often least costly) fix. "If- it -don't- work" move to the next level and so on. Facthunter's comment would be my thinking on oil filter failure, that is this is UNLIKELY sceneriao. However the idea has some merit as its cheap and easy enough to be attractive IF there has been a history of failures in recently installed filters causing oil pressure reading anomalies. I think I might just check this out with Flood's.

IBob - I don't have a calibrated master oil pressure gauge. The rapidly fluctuating needle is not a regular (predictable) occurrence so it will be pure chance that I get any useful information on this but the very slight drop in oil pressure reading concern (still within Rotax specifications) may be put to rest by using such a gauge - will see if I can borrow a suitable master gauge.

All the excellent advice has focused on the sender, gauge and integrity of the wiring - no one has commented on the idea, promoted by John, that the oil filter may be causing the problem. For myself I note that my aircraft's change in oil pressure reading seems to have occurred/first noticed, after an oil/filter change. My oil filters are supplied by Floods, the oil is AiroShell Sport PLUS 4 - all by the book. If the filters are known to occasionally malfunction in this way, it's a fare easier/cheaper fix than anything to do with the oil pressure read system. Anyone care to comment!

I have long recognised that 12 volt automotive systems are prone to earth return problems, so much so that I have fitted my 912 with additional earthing cables to ensure good continuity . I have also done this with all my older (pre computer) vehicles. The small additional cost has resulted in more efficient electrical & longer component operational life. Lights shine brighter, globes contacts/switches & batteries last longer. In short I don't think I have a earthing problem (but will check anyhow).

Hi Geoff - Will check out the sender, next visit to aircraft - gauge definitely not Avia (think Speco). With exception of calibrated "Master Gauges" I have always understood that you read the gauges as fitted as indicative only and be alert to changes/deviations from normal/expected readings. I have had the privilege of owning my aircraft for about 7 years and am the third owner. I am fairly sure sender & gauges are as fitted in 2000 by original owner/builder, so are 16 years old. It could just be the sender and/or gauge are a but tired or it could be the beginnings of something more concerning.

Hmmmm - my 2000, 912 (100hp) operating on 98 RON Mogas has 720hrs. Very recently (after the last service) I noticed a small drop in operating oil pressure. So small it could be my imagination, but its consistent. Start up (cold) pressure is as normal, dropping as temperatures rise - all expected. Engine oil and coolant temperatures all normal. I have noticed the occasional rapid fluctuation of the needle and an occasional drop (below normal) as RPM rises for takeoff, followed by a return to near normal pressure readings. Any cause for concern ?

KR - Your RV sounds like a real beut. I am sure you would detect just a little envy in me should I ever have the privilege of seeing it - I wont argue with your RV in the air for under $60K costs, but remain sceptical, sorry!

A year or so ago I had the privilege of a " joy flight" in a plans built RV4 from Wedderburn NSW - the fit/finish, down to the smallest detail, was pure art, way better than any factory build. After a barrel & aileron role or two I was ready to go out and buy my own - a truly wonderful aircraft and pilot/builder.

A long time ago I used to fly Cessna 172's (up to constant speed/retractable level) 150 -180 hp engines, if a remember correctly (always a concern) I planned for fuel burns of about 32 - 38 lph. In my Zephyr/Rotax I plan trips at 14 lph and actually use less than 13 lph, one up and 13.5 lph, two up, at 100-105 knots indicated. I can cruise faster, up to 120 + knots (but why?) with commensurate fuel burns up to about 18 lph (bit hazy as I don't often go here). For local flights I usually see consumption rates of 8- 10 lph or less for the "mission". I know of no aircraft petrol engines of similar hp (other than Rotax 912is) that can come close to these "real world" sort of fuel flows. For even better independently verified figures check out VH SGS / Sonerai built by Robin Austin.

Oh I know the "sky's the limit" with avionics and if what you have fitted suits you (& your pocket) more power to you. I like to keep things simple (& cheap) - small round dials for the most part. I have splashed out on a KT74 (ADS-B) transponder (not required but I like the enhanced safety), an iPad mini/OzRunways, a Garmin GPSMap back up (both on RAM mounts) and for fun (& some added awareness) an AVMap Ultra EFIS. Once in a while I contemplate an autopilot but so far have resisted. I fly out of a very "dodgy" home strip, so have my ground adjustable prop pitched/optimised for climb - would be nice to have an in-flight adjust or CS prop for cruise (enhanced speed/economy??) but at $9-12K (including governor & engine mods to suit) for a reputable unit, I don't know if this will ever happen.

You can put an all new ATEC Zephyr (very quick build) in the air for about $90 - 95K, an all new Faeta (all carbon,factory build) will cost somewhere in the region of $120+K depending on engine/avionics choices etc.

KR - did you really put an RV9 in the air for just $75k AU?? if so it must have been a squilian years ago (or you are a close relative of Dick V's).

I recently witnessed the deceased estate auction of a Seawind (near rebuild completion after an accident) with its 300+hp engine (supposedly 0 timed by Hawker Pacific), CS prop, etc, sell for $27k AU, so great deals do happen.

I fly RAA to keep costs as low as possible, so + $6/hr sounds a bit rich to me (around here it would be more like $7) In truth, I suspect you might be closer t0 an extra 4 gallons/hr = 15 litres or $22.50 ULP/hr). I fly 80-100hrs/annum - go do the maths.

Virus SW is not cheap by LSA standards, but assuming day VFR only, I don't think fitting it out with $20k of instruments is either necessary or cost effective - $5-10k should do the job very nicely.

True the SW wingspan is somewhat wider/longer than many small aircraft but then you can always park your RV( tail dragger)'s under the wings.

I change my 912's oil every 50 hrs (only 3 litres) but as I run only ULP, I am told I could go to 100hrs. (I also service my cars under the "extreme conditions" intervals just because it satisfies my inner obsession.)

The Rutan type aircraft are very attractive (as are RV's) but few of us are just after speed, things like TO/landing role, stall speed, noise levels, rough filed capability & comfort become a significant part of the consideration.

KR - RV 9 nice aircraft! Always liked the look of the RV line - BUT! the use of SMPH (165 smph = 143.4 Kn) is giving you a false sense of performance when compared with Virus SW, Soneri & a host of other Rotax (100 hp) powered aircraft that can equal or better your cruise speed, lower stalls about half the fuel consumption and longer cheaper service intervals which all equates to much lower running costs. True your RV may be able to out climb most of the Rotax powered aircraft but countering this is the length of runway you require to TO & land.

Xavier - Maintaining a simple aircraft, like most found within RAA, is just a matter of being able to read a maintenance manual & follow the directions to the letter (being obsessive here is very important). You will need a few basic tools, nothing fancy or costly. I am sure even in the tropical heat of Darwin you would easily find a helpful like minded flying friend (perhaps your LAME) who would willingly help you over any difficulties. The satisfaction in "doing it yourself" is worth far more than the $$$ saved.

My apologies to all - I made a classic mistake, I got myself fixated on aircraft fitted with Rotax 912's (just a little bias showing).

Of course there are faster aircraft, they tend to have larger capacity direct drive engines and stubby wings. For the most part are only RAA legal with one person on board, need very long runways & fly with partial fuel, but they are legal, JUST! These aircraft wont win a CAFE Challenge - they burn to much fuel and don't carry two people - in other words they are not very efficient but some are very fast.

Still VH SGS / Sonerai built by Robin Austin could be registered RAA, carry two people and with only a Rotax 912 (100 hp) is able to take on aircraft commonly using engines of 150 + hp and do it all on nearly half the fuel (unleaded) burn - that's truly fast and efficient.

xespiou - no offence intended to you or the many great LAME's out there.

I applaud your efforts to capture the real cost of your passion.

My conversion from GA to RAA was/is mostly cost driven, so I like to keep my my flying costs as low as possible, consistent with safety.

For some of us, part of the passion of flying is the pleasure in doing as much of the aircraft maintenance as we can. This has the duel benefit of satisfying our obsessive natures and saving cost.

Your LAME cost just gives me a very satisfied grin

kasper - Now you are talking! There are a lot of fast/sexy looking aircraft out there with truly wild/unverified performance claims. A truly informed observer/purchaser looks for the independent assessments on which to base their opinion - all else is wishful thinking .

Check out the CAFE Foundation that hosts NASA's PAV Centennial Challenge for small aircraft, - wikipedia.org/wiki/CAFE_Foundation

DGLFox/ Sting, might like to check out the Pipistral Virus SW (also on the RA Register) two time winner of the CAFE - may not look as fast/sexy as the Sting - it doesn't have to as its independently verified performance makes the Stings unverified performance look positively anaemic.

19 Rego - why pay a LAME to service your aircraft?

ASI's are notoriously inaccurate - independent third party verification, taking into account the many variables that can effect the result, is the only credible claim/measure.

Objective results are the only valid measurement - check out the Pipistral Virus SW & VH SGS / Sonerai built by Robin Austin. Powered by 912 (100 hp )engines. Both these aircraft are world competition winners, so their performance has been independently verified, unlike the wishful claims of most aircraft manufactures in this class of aircraft.

First rule of aircraft maintenance is: If the manufacturer describes the procedure and materials to carry out a job, then that is the way to do it.Second rule of aircraft maintenance is: If the manufacturer does not describe the procedure and materials to carry out a job, then follow AC43.

OME

Do you have a strip at Razorback?

Dafydd

The UV block issue concerns me - Stewart System (SS) insist that their paint products do not require additional UV protection (even in Australian conditions).

I have invested a great deal (by my standards) in the SS, so will follow through, although I confess to continuing disquiet. Time will tell.