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-   -   alternative for facet fuel pump carburated engine (https://vansairforce.net/community/showthread.php?t=148920)

170 driver 04-24-2017 06:07 AM

alternative for facet fuel pump carburated engine
 
Does anyone have any experience with other types of low pressure electric pumps? I'm trying to find an alternative to the facet pump. There seems to be a lot of failures. Mine included. Is anyone using a filter before the inlet to the pump?

Mel 04-24-2017 06:17 AM

Quote:

Originally Posted by 170 driver (Post 1167925)
Does anyone have any experience with other types of low pressure electric pumps? I'm trying to find an alternative to the facet pump. There seems to be a lot of failures. Mine included. Is anyone using a filter before the inlet to the pump?

Same pump since May of 1993, no problem. I do have filters ahead of the pump.

170 driver 04-24-2017 06:21 AM

Mel, does your filter have AN fittings or is it rubber line and clamps? I was trying to stay away from rubber and use an fittings on everything.

Mel 04-24-2017 06:56 AM

I use rubber hoses with clamps. YMMV.

Tomcat RV4 04-24-2017 07:33 AM

You can get same pump at most auto parts store, tell them it's on your tractor !

snopercod 04-24-2017 08:38 AM

Does it look like this, or is it one of the "cube" types?


Sam Buchanan 04-24-2017 08:41 AM

Quote:

Originally Posted by Tomcat RV4 (Post 1167948)
You can get same pump at most auto parts store, tell them it's on your tractor !

Be careful, some Facet pumps at auto parts houses contain a check valve to prevent fuel flow with the pump off. Check the spec sheet for the part numbers with correct fuel flow and no check valve:

http://www.aircraftspruce.com/catalo...?clickkey=4377

http://www.facet-purolator.com/cube-fuel-pumps.php

170 driver 04-24-2017 09:05 AM

it is a cube one, rattle pump. 4 to 6 psi I believe. I have a Van's replacement ready to go back in but I wanted to see if there was a better one out there.

rv7charlie 04-24-2017 06:08 PM

I suspect that you hearing about 'a lot of failures' is a simple quantity measurement, and not a percentage measurement. When there are thousands (or hundreds of thousands, or millions) of a device in operation, there will be 'a lot' (in quantity) of failures. Failure *rate* is another matter entirely. And if you read carefully, it's fairly common for those who bothered to investigate their 'defective' pumps to discover that the only thing wrong with them was a piece of trash stuck in the pump (hardly the pump's fault).

Those pumps are actually designed for continuous duty in various non-aviation environments, so if fed clean gas, most will easily last the life of the airframe when used as a backup/boost pump.

Hey Sam, I might be wrong, but aren't you thinking about the PSO (positive shutoff) valve, and not the check valve? If I understand it correctly, the check valve shouldn't prevent flow with the pump off; it just prevents back-flow if you have a pair of pumps plumbed in parallel.

170 driver 04-24-2017 06:41 PM

Yes I agree about the percentages, but there are more than a handful of failures documented on this site and only one could be disaster. I'd prefer to use another pump if there is another proven option available. Mine probably has trash in it too and I'll put filters before the fuel selector in both tank lines now and replace the pump.

Sam Buchanan 04-24-2017 07:32 PM

Quote:

Originally Posted by rv7charlie (Post 1168141)

Hey Sam, I might be wrong, but aren't you thinking about the PSO (positive shutoff) valve, and not the check valve? If I understand it correctly, the check valve shouldn't prevent flow with the pump off; it just prevents back-flow if you have a pair of pumps plumbed in parallel.

Yep...I am...I think....

Point being there is reason to select a Facet with care, not all are suitable for our application. I'm using two Facets (primary and backup) full-time on my latest project with a non-mechanical pump O-200. The things were designed to run full-time for years in the automotive world.

Kyle Boatright 04-24-2017 08:24 PM

Quote:

Originally Posted by 170 driver (Post 1168152)
Yes I agree about the percentages, but there are more than a handful of failures documented on this site and only one could be disaster. I'd prefer to use another pump if there is another proven option available.

I don't think you're gonna find an option out there that has 5,000+ in service and a relative handful of failures. You may find a different option, but you'll have a hard time finding any statistically useful information about it or its service history.

rv7charlie 04-24-2017 09:02 PM

Quote:

Originally Posted by 170 driver (Post 1168152)
Yes I agree about the percentages, but there are more than a handful of failures documented on this site and only one could be disaster. I'd prefer to use another pump if there is another proven option available. Mine probably has trash in it too and I'll put filters before the fuel selector in both tank lines now and replace the pump.

There are any number of failure modes in any number of devices that could be disaster. And any device can fail at any time, regardless of reliability. Our job is to have a plan B. With a typical Lyc installation, the Facet is plan B. For its failure to be a disaster, you'd need a failure of the engine driven pump *and* a failure of the Facet (you test before every flight, right?) *at the same time*. If that happens, I think your number's up.

deek 04-24-2017 10:39 PM

Same Facet pump since 1982 - about 3,300 hours. Female NPT ports; gets used at least 3 times every flight.

170 driver 04-25-2017 05:59 AM

Thanks for the input from all, looks like I missed the memo on puting a filter before the pump. Fairly easy to fix and hopefully will solve my problem.


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