Fuel pump unnecessary

[ZU BBV]

Thank you all for the help on my fuel pump query. I am really impressed with how the more experienced pilots can make time to help with stuff that is long forgotten to them. But!! There are lots more to come as I fly by myself (no other trikes in the area) and don’t have the guy next to me in the hanger to say, Hey! How do I….?

Peter

[Morph]

and don’t have the guy next to me in the hanger to say, Hey! How do I….?Peter

You do, right here.

The fact that you fly alone is even more reason to make sure you cover your bases well.

[Boet]

In hierdie game, vriend, sit jy n BELT EN KRUISBANDE aan!!

[Sad-Ham]

Thanks..... will go see if I can get one

[John Boucher]

I agree with all the FOR an ELECTRIC FUEL PUMP!

I am busy doing the my Cheetah's engine mounts over, refitting my radio when it's back from repairs ( thanks ZULU1, installing a VSI (thanks Duckie...) and yes will be installing the Facet Electric Fuel Pump.

Having taken the engine out, I have found some decaying wiring and some other potential problems. Jabi's & Bliks use an electric fuel pump so why not - the advantages outweigh the single negative incident! So whilst on a roll to fix all in it goes - I do the check anyway when flying!

[lefssa]

An extra fuel pump saved my plane. Started running rough, with pump on i made it back to field. I got some dirt in fuel from a "borrowed" can. Will never use any can but my own from now on.

[Morph]

Ranger had a save as well. A few years ago flying back from somewhere along the southern coast, he was over the big klippe around Franschoek when the motor started loosing revs. Quickly switched the pump on and revs came back up. Not much place in this valley to make a precautionary. After a few minutes switched the pump off and it flew fine for a while before loosing revs again. Once again pump switched on and things came back to normal. Eventually made it back to Morning Star and after long investigations discovered the breather hole in the top of the tank, had a little piece of plastic obstructing it, blocking the airflow and thus starving the carbs. The additional suction of the electric pump managed to force air past the obstruction

[IceAge]

Going through this thread and reading the various comments I also have a few questions on the fuel issue. I don't hope I am highjacking the thread, but

1) I have seen, thus I do it myself, pilot's pouring the fuel, after checking for water, onto the air filter. Does this help any, ie. does the now 'fuel rich' air being sucked into the carbs from the air filters help with startup or it is just a way to have the filters attract dust ??

2) Should one, as part of some maintenance routine, drain the fuel tanks to get rid off 'goo' in the bottom of the tank and if so how often ??

3) Something I learnt at a Rotax course when fitting an electric fuel pump in serial to an existing non-elecric fuel pump you must ensure that the pump with the least pressure by closest to the carburator. Did I understand this correct or was it during a moment of daydream-flying that I misinterprited ??

Fly safe

[Morph]

1) I have seen, thus I do it myself, pilot's pouring the fuel, after checking for water, onto the air filter. Does this help any, ie. does the now 'fuel rich' air being sucked into the carbs from the air filters help with startup or it is just a way to have the filters attract dust ??

Never seen this done, unless he is using it as a way to "enrich" the start. Maybe his chokes are not working

2) Should one, as part of some maintenance routine, drain the fuel tanks to get rid off 'goo' in the bottom of the tank and if so how often ??

Good question, I would look at doing it once every 100 hours, or once a year unless you are in a very dusty dirty environment. However if you pick up a problem with gunk getting through and blocking the filters, then I would do it immediately. Also if you plane stands for a long time, worth checking inside the tanks for gunk.

3) Something I learnt at a Rotax course when fitting an electric fuel pump in serial to an existing non-elecric fuel pump you must ensure that the pump with the least pressure by closest to the carburator. Did I understand this correct or was it during a moment of daydream-flying that I misinterprited ??

The mechanical pump, which is also the fuel distributor must be closest to the carbs

[IceAge]

Thanks Morph

Will make it part of my maintenance schedule to 'rinse' the tank at least once a year or every 100 hours even if not part of the recommended schedule. Do however, as I am a 'bangbroek', replace my fuel filters every 25 hours.

Fly.......... and land safe !!

[John Boucher]

That's what we call preventative maintenance.....

[lefssa]

I only replace my fuel filter every 100 hours but use a see through one. I can see if it is clean. i use the ones from Aviation Engines, they are fairly pricy but worth it. About R80.00 each.

[Wargames]

I only replace my fuel filter every 100 hours but use a see through one. I can see if it is clean. i use the ones from Aviation Engines, they are fairly pricy but worth it. About R80.00 each.

Just becareful about the visual check. I had a chat to Jannie from Springbok(he is instructor and ap) and he told me about a training course where they discussed fuel filters. They were given one, asked if it was clean, and then asked to blow through it. Then they were given a new filter. Asked whether it looked any diferent from first one, he said no, and then had to blow through it. He said he couldn't believe the diference in volume that was blocked by first one, and it LOOKED CLEAN!!

Rather change it every 50 hours just to be sure. And be sure to check inside your tank.

"Tongue in cheek ... circle above your field untill engine stops with fuel empty. Do a "forced" practice landing. Clean fuel tank. And there you go. repeat every 50 hours."

Happy flying.

[lefssa]

Thanks, Look like i am going to be buying more filters. A comment like that is very welcome.

[Morph]

This actually all really depends on your environment. If you are in a dirty dusty environment, plane stands for long periods of time, out of sight and mind, then there are very real risks of fuel contamination. Metal fuel tanks are more prone to water ingression for example, purely due to expansion and contraction of air and humidity. The humid air gets drawn into the tank through the breather pipe during contraction, i.e. cooling and then condenses on the sides. The water then runs down the walls and ends up at the bottom. If you are in an environment that is high in humidity then water checks need to be done every flight. In the 2 years I had my Challenger at Morning Star, it had a metal tank, and although I checked for water, I never found any, so perhaps a less frequent check would be fine

Bobman bought a Challenger that had been used on a farm for the last 5 years. When the fuel tank was inspected it had a thick layer of red sand in the bottom. The fact that the whole aircraft, inside and out, was caked in this fine dust should have been an indicator. In a dusty environment, then inspections and filter changes are more frequent.

Winter months, vs summer months also require different frequencies. Winter in the Cape and summer up in Jozy are the wet months, less chance of dust but more of pollens. the opposite seasons are very dry and dusty so increase your rate.

However, your biggest risks to fuel contamination are
1. bad fuel from the garage (look inside the bottle for water drops or dirt on the bottom). If unsure use a chamois cloth over the mouth of the fuel tank to trap moisture and dirt.
2. dirty containers, (you might borrow a container from somebody, that was used for water, oil, be very dirty etc)
3. Dirt inside your syphon tube. Even one hanging in a hangar can get insect nests inside and dust. One carried in your belly bag/panniers can pick up sand and dust, fluff, lint from cloths etc. Keep it closed in a plastic bag
4. a new Tank. (this one nearly killed me) be very very careful when you flush it out. Even if you think it is clean it might not be.

Then adjust your frequency of inspections to suit your environment. Some guys only change fuel filters every 200 hours, others 25. Perhaps it's worth cutting them open to see how blocked and dirty they are. The opaque plastic disguises a lot.

The reality is this, fuel problems are your number 1 cause of engine problems.