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Andair Fuel Pump - Mount (Video)

Phil

Phil

Well Known Member
On an earlier thread, I promised a video of my Andair Filter/Pump installation. Yesterday I finally got around to grabbing some video and getting it posted on YouTube..

http://www.youtube.com/watch?v=x3mpcapeBA8

I shot a second one on the Bonoco brake lines through the tunnel and should get it uploaded tomorrow.

Phil
 
hard line

Phil----Nice installation. You could put in another couple of bends in your output tube to attach it to the side panel, and save a bunch of money on the "TSO'd" hose assembly.
Tom
 
Andair built a different moustrap, but better?

It is nice that the Andair pump has a built in bypass for the pump but the Van's setup actually has TWO bypasses; one for the pump and one for the filter. In the Andair configuration, if you attach the output from the selector directly to the filter, you do not have a bypass for the filter in case you have a catastrophic clog of the filter.

Adding my $0.02 to the hard line vs flexible line debate; behind the firewall, a well secured hard line will ALWAYS outperform a flexible line and never need replacing. Personally, if I bought an airplane of any age over 5 years, I would replace all flexible fluid lines; even the "no life limit" Teflon lines. Many experience pilots and A&Ps subscribe to this.
 
w1curtis said:
the Van's setup actually has TWO bypasses; one for the pump and one for the filter.
Click to expand...

William, do you have a diagram showing the fuel filter bypass? I've looked at Van's AFP setup and clearly see the pressure relief bypass, but don't see a filter bypass. Would like to understand how fuel would get downstream from the AFP filter if the filter were to clog.
 
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A couple of items that I forgot to mention on the Andair pump and it was a huge selling point (too) are the mechanics for moving the fuel.

The Airflow pump has vanes and wears similar to the old vacuum pump. This means there is friction and wear occurring within the housing. Andair took a different approach with a series of rotating cavities that are constantly contracting on the low pressure side and expanding on the high pressure side. This means the pump siphons fuel through it and there is no wear within the pump. The AFP nice, proven, and serviceable. But IMHO, the Andair pump is a much more elegant design.

Also, I forgot to mention these in the video:

1) The DC connections are going to be on a twisting connector so I can disconnect the pump from the wiring and put everything on the bench every annual to service the filter.

2) The screws holding the plate to the bracket are 1/4" Hex Head/Phillips screws. So I can hopefully use a 1/4" ratchet on them when I'm reaching up in the tunnel. But if I strip them off for some reason, I can use a wrench and if that doesn't work I can use a screw driver.

3) You'll notice the fuel flow transducer is missing between the output of the pump and the firewall. This is because I'm moving the transducer into the cowling like many others. (More distance from the pump results in more accurate readings when the boost pump is on.)

I'm sure there are a few other items that I missed, but these are the ones I can think of this morning.

Phil
 
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Auburntsts said:
William, do you have a diagram showing the fuel filter bypass? I've looked at Van's AFP setup and clearly see the pressure relief bypass, but don't see a filter bypass. Would like to understand how fuel would get downstream from the AFP filter if the filter were to clog.
Click to expand...

Chapter 37, page 4. I did a quick drawing but can be seen in the below picture.
fuelsystem1.jpg


fuelsystem2.jpg
 
Hmmm. I thought the valve on the bottom of the diagram was the pressure relief valve, not a filter bypass. If so, there is no filter bypass indicated on the diagram. My understanding is when the boost pump's off, fuel flows through the filter and check valve and on to the mechanical pump. When the boost pump's on, fuel is picked up at the Tee between the filter and check valve and pushed through the manifold to the downstream side of the check valve where it enters the fuel line on to the mechanical pump. If the line gets blocked downstream, pressure builds until the relief valve (the bottom valve in the diagram ) opens and allow fuel is returned to the Tee between the selector and fuel filter creating a loop. But the flow is always one-way. Downstream on the top and middle lines of the diagram, and upstream on the bottom. Just not seeing a filter bypass in there anywhere. IOW it still appears to me that the filter is still a single point of failure regardless of Andair or AFP system and that both system operate the same way -- except Andair 's pressue relief is internal while AFP's is external. Am I missing something?
 
Phil, one question I like the Andair what you've got is the one with AN6 fittings but it is good according their tech sheet for 16 gallons with 27-30 psi. Looking at the sheet for an IO-540 it says full power sea level are around 22 gal/h. It seems a bit strange, that Van's went with the 3/8" fuel lines instead the larger 1/2" for the IO-540. Do I miss something here?

Thanks for a clearing info

BTW anyone having the data for the ES Airflow pump?

Werner
 
Phil,
Thanks for posting that video. I wish I had seen your idea long ago for the 'locating pin rivets'. Oh so simple. I really like it.
Steve
 
glastar said:
Phil, one question I like the Andair what you've got is the one with AN6 fittings but it is good according their tech sheet for 16 gallons with 27-30 psi. Looking at the sheet for an IO-540 it says full power sea level are around 22 gal/h. It seems a bit strange, that Van's went with the 3/8" fuel lines instead the larger 1/2" for the IO-540. Do I miss something here?

Thanks for a clearing info

BTW anyone having the data for the ES Airflow pump?

Werner
Click to expand...


Hi Werner,

That's a question many of us raised too. See this thread.

http://www.vansairforce.com/community/showthread.php?t=62884

Van's uses the 3/8" lines and Andair's recommendation is for the 3/8" fittings on the RV-10 pump.

I find it bizarre too, but I'm deferring my decision to Van's and Andair's engineers.

Phil
 
Hello Phil,

I had a question with Andair in already when I posted my question here their answer states, that the free flow is large enough:

Dear Werner,
The PX375-TC will be more than satisfactory to supply your IO540. The pressure relief valve is set at approx. 35psi.( That means in the 'No Flow' condition the relief valve opens and the pump recirculates internally)
Flow at 25/28psi would be at 30 gal/hr.
Click to expand...

I will however ask about what when engine pump fails ;) and post comments here.

Anybody out there having the technical data for the ES Airflow pump which Van's sell?

Thanks

Werner
 
It should not be a big deal when the pump fails because you still have the mechanical pump. It's only switched on during engine start (to prime the system), climb out, and landing (in case you need to go around and climb out again).

If it did fail the flow rates might drop just a touch but not enough to be noticeable.

I've flown FI engines with the pump accidentally turned off during TO/Landing without the boost pump running. It's not problem but also not something I would make a habit of doing.

A lost boost pump should not be an emergency. A blocked filter is though. ;)
 
Hello Phil,

I did think what if the mechanical pump fails (then relaying on the electrical). But Andy from Andair just confirmed, the PDF on the web is outdated:

Our spec. sheets don't seem to keep up with our pump development, yes 30gal/hr at approx25/28psi. We will get the pdf changed in the morning!
Click to expand...

So it is clear for me the Andair instead of the ES Airflow.

Cheers Werner
 
Awesome... That had me quite confused too.. I couldn't figure out why Vans when with 3/8" lines if the pumps didn't match.

Good stuff.

BTW - Just got a phone call that the finish kit is waiting on me at the airport. I get to drive out there tonight, load it up, and bring it home. :)

Phil
 
Filter bypass addressed?

Phil,

Was a conclusion reached on whether or not the Andair pump (or your installation of it) has a filter bypass for a clog? Not knowing much about fuel systems, I am not sure how most aircraft are plumbed with regard to the filter bypass and I am reaching that stage of the build. In fact, I was removing the Vans supplied fuel flow transducer mount this morning (QB).

David
 
David,

The Andair setup does not have a clogged filter bypass. I can't speak for the Airflow Performance setup, but I don't think it does either. I'm sure someone will correct me if I'm wrong about the AFP - it is the internet after all. :D

The Andair setup is really nice though and I like the way it came out. The only thing that changed after I shot the video is that I decided to keep the longer aluminum fuel line. I added a couple of supports with adel clamps to support the line. You can see a photo of it here...

http://www.matronics.com/forums/files/photo_497.jpg

Phil
 
Safety Heads Up

A Safety ?Heads Up:?

Unfortunately, a recent inspection/test of a new, but failed, Andair fuel pump discovered three potential design and/or manufacturing problems:

1. Check Valve O-Ring Security.
2. Anti-Rotation Pin Size and Fit.
3. Pump Component Wear.

See the following current thread including Andair?s response.

http://www.vansairforce.com/community/showthread.php?t=71529

Particularly, watch the failure analysis video.

Until Andair comes up with flight-acceptable fixes/dispositions for each of these three problems, it would seem prudent from a safety standpoint not to install or fly an Andair fuel pump . . . my opinion, anyway.

Build and Fly Safely,

Bill Palmer

P.S. My Andair fuel selector is great; I?m surprised that Andair?s fuel pump design/manufacturing has become an issue.
 
Thanks Phil...and Bill....

...for your responses. Bill...it seems like you hit a nail on the head with your assessment of the pump seeing as Andair not only talked about some of these issues but has also addressed them with their new design. Nice job!

As usual, it looks like a judgement call needs to be made to either stick with tried and true (Vans/AFP) or go with the Andair pump (newer version with improved design to address the issues that Bill pointed out).

David
 
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