Microlighters

This is one extra I will always have on my planes. I have already nearly had an engine out due to clogged and dirty fuel filter and with a simple flick of the switch, the pump came on, and forced the fuel though to the carb, and saved my then quivering bacon. Sabastian asked me for details on how they are installed so I thought, might be a good idea for a post.

A Facet pump is readily available at any car spares supplier, it allows free-flow of fuel through the pump, so can be left off, but should there be a problem switch it on. It is also great for priming the carbs prior to starting. Switch it on, you will hear the pulsing sounds change from a sharpingish sound to a dull thud and the system is pressurised. ready for starting.





This image is from a trike. In this case the Facet pump is installed before the filter, it can be either way

Thanks for the advice!

Added to my overhaul to do list!

Realy a good idea, which should be standard

I flew yesterday touch and go, low level, and the pax I had asked me, why I switch on my electric fuel pump and not during the flight.
If I am low, and my mechanical pump fails what when

So normal procedure is electric fuel pump on, on take off and landing, and sure on low level.

An electric pump does not cost a fortune and helped as well Morpheus with a slight blocked filter

I like that fuel filter you have fitted too morpheus - what is it called and where can it be found?

I have an Aerotrike with a 582 like you but it was nowhere as neat when I took it over...

OK, so let me get this right. you have a electric fel pump between the tank and standard pump, and this then forces fuel into the standard pump?? If so, what about flooding / over-pumping?? is there a pump that is specifically for this scenario, or is it a normal pump from like midas or something??

That is why you have a float chamber to cut off the fuel supply when there is too much... It will keep on pumping but it will hit a "brick wall" so to speak when the float closes off the float bowl when full. When the float bowl empties out the floats lower and open the valve to let fuel in again.

At least that is how I understand it...

The fuel pump cannot force any more fuel into the carbs as they are prepared to take. All you are doing is pressurising the system. The pulse pump uses a diaphram driven by vacuum coming from the engine. If you get a piece of grit in there, or a crack in the vacuum pipe, or a few bubbles in the fuel lines from a crack in the fuel lines , or gunge in the fuel filter the pulse pump just does not have enough pressure to clear the blockage and you get starvation. The electric pump can and does replace the malfunctioning pulse pump in these circumstances.

As 150 says he uses it during takeoff, landings and low level. I like to use mine when I am carrying passengers and the terrain is not the best for engine outs, just gives me added insurance.

The pump is a standard FACET (brand name) electric pump obtainable from any car spares place.

I like that fuel filter you have fitted too morpheus - what is it called and where can it be found

I don't know DH, this is a friend's plane and he bought it with it installed.

Great minds think alike DH - if you find out what make the fuel filter is let me know. Looks like a real mil spec piece of equipment - I will try and find out from my side.

Good idea!

Query: Is it not better to have it installed before the fuel filter?

Is the Facet electric pump just as good at sucking as it is at pressurising liquid?

The fuel filter is the first place where gunk can accumulate.
I suspect the Facet pump is only really good at pressuring liquid, so it will only really help with fuel flow problems after the pump, hence my query to put it before the filter?

Thanks in advance
Kind Regards
Rudi

It works equally well before or after the fuel filter. If you are retrofitting it in a plane it would depend on where you could mount it. In my plane the only mount point was halfway between the tank and the engine, the fuel filter is right at the tank, so instead of re-piping the whole system it was easier to insert it in-between. I have seen some with a seperate pickup point, filter and piping and then joining just before the pulse pump. Horses for courses.

Morpheus, ja, it works equally well untill.....
Redundancy means circumventing any one failure along the line, why use only one filter?
The AA (as in automobile, not alchohol) stats shows 80% or so of roadside failures of cars were due to waterpump drive belt or coolant hose failures, but I reckon 9 out of 10 microlight engines failing in flight were not getting enough fuel.* Exibit A: a gunked up fuel filter due to contamination of synthetic with mineral 2-stroke oil. (I had just enough height to make a small instant lawn field, ducking under a telephone line. Blew out the fuel filter and promptly took off again**, but by then the prospective plane buyer in the back seat had lost interest, I still wonder why?)
I have not flown without dual fuel pumps and pre-filters since. They weigh and cost little enough, so do not argue, just fit. Note to the logic-impaired: not two vacuum powered pumps, and if two electric, wire independent power feeds. I have since had a Bosch rotary pump stall on a blade of grass! that got through the MB diesel strainer. A double reed valve pump like the Mikuni vacuum powered or Facet electric coil powered can fail on a grain of sand embedding on a seal.
*First cross-country with passenger, flat out on the 503 but out of fuel after 40 minutes (like Demon, luckily in gliding distance of destination) Phone Blythe, says usual problem, choke stuck in open position.
Bliksem, we barely made it over the trees, but on the intercom I just said: "Nose down, building speed..."

Thanks for the good advice .Abe , it sounds to me that sould be more careful when you put feul into the feultank. How about a filterdevice when you pour fuel in the tank? Then again You are just unlucky.

I found one today at my local Autoparts store. R213 excl.

She is a heavy one, just below 0.5kg... But I think worth it AS for the model number - I cannot figure out what it is, it is a 12V Negative ground though - Made in the USA...

http://www.facet-purolator.com/solidstate.asp

As for the monster filter I am still shopping around - will advise

DH,
little bit more of safety does not even come expensive