Fuel Selector Valve

[lsa140]

Does anyone know what type of fuel selector valve Bob used on the LSA? From the photos it looks like a 4 way selector valve you would find at a marine supply store.

[Mark Goldberg]

I think Bob buys a $30 valve and modifies it so it has Left/Right/Both positions. We recommend the SPRL valve to the kit builders (over the Andair) because it has the outlet on the side rather than on the bottom. The SPRL fits in the boot cowl bottom without a blister/bubble. Mark

[lsa140]

Thanks Mark. I couldn't find one with the right combination of ports and positions online. I wondered if he modified the porting in the ball.

The SPRL looks good. I'll go that route.

[Battson]

The only minor issue with the SPRL is that the outlet is on the front.

That means that condensing water, collecting in the fuel system overnight, would pool at the selector valve. If there were a downhill angle, it would be flowing through to the gascolator when the fuel selector is set to both during pre-flight.

I couldn't solve that problem, short of installing the valve back-to-front. Therefore I rely on the tanks catching any water which might collect in the system. That, plus running the engine long enough to clear any water before take-off.

BUT - I have fuel injection, which can cope with water in the fuel system. But I understand water can block a carburettor completely.... so that might be a more dangerous situation? I can't say...

[jaredyates]

I just installed the SPRL backwards and relabeled the L and R positions.

[whee]

Question for those that have used the SPRL valve: how was the machine work? Couple weeks ago I ordered and received a SPRL duplex valve and the machine work was terrible like a dull bit was used, threads looked like they were cut with a tap from Harbour Freight and when the selector was turned it felt like a o-ring was catching. I could have gotten out a file and cleaned up the machine work and put a bunch of thread sealant on the threads to get them to seal but the rough spot in the operation of the valve was a deal breaker...we sent it back. We did order another one and are hoping it will be better.

[Battson]

Mine was very well made - sounds like you struck a failure of their QA process, maybe.

[RSV]

Hi Whee,
I make the SPRL valves.

I have just had your rejected valve back from spruce, via OSH.

It seems perfect to me- the usual quality finish and smoothe operation.
You are right that the he threads you complain about look a bit rough but they work fine. The seal comes from the O ring so adding sealant will not affect the valve function- but a bit will help ensure the fittings do not back off in use. You will find that the adaptor fittings we supply will seal perfectly even finger tight.
The npt fittings do rely on some sealant as the thread design is truncated and would otherwise leak.

Frankly I would prefer you understood the function of the device before making public criticism.

For those worrying about water and 'sumps' It seems to me that the problem is poor fuel caps; contrary to common talk of 'condensation', water in the fuel is rain so if your gas caps seal you will not need to worry about water in the system.
happy landings.
RSV

[whee]

RSV, Good to hear feedback from the manufacture. However, I stand behind my criticism. Leaving burrs like that in the ports after the machining is not acceptable. I have no doubt the threads would hold and saw the shoulder the o-rings seal against on the supply side. The return side NTP ports would have sealed with enough sealant but really...on a $300 valve the consumer shouldn't have to deal with rough threads and burrs in the ports.

Like I said, the deal breaker was the slight hang when turning the valve to the off position. It sure felt like a o-ring catching and with all the other burrs in the ports I wasn't willing to risk it. The replacement valve operated nice and smooth so I took a file to the ports and chased the threads with a bottom tap. Should be good to go now.

[lsa140]

Battson, is there any reason that the valve can't be installed back-to-front? I realize the directional engravings would be off, but it wouldn't be difficult alter them or make a new faceplate that installed over the original. That would clock the handle so the point facing forward was "both". I'll be flying in weather conditions and terrain very similar to you, and even up into the arctic. I don't mind spending time getting the fuel system right.

The system Bob has drawn in the LSA book shows a strait shot from the selector valve to the gascolator. The gascolator ports are in lined up fore and aft.

Looking through the Bearhawk Builders Manual, it looks like Eric installed a similar (to Bob's) 3-port selector valve that must have a both setting added. All of the 3-port valves I can find are left - off - right. I'm a little intrigued now by what modifications are done to make these valves 4-way. I understand why it hasn't been advertised though, mishandling the modification could be catastrophic.

[Battson]

Apart from re-marking the face of the valve, I see no reason why you couldn't do that.

[Mark Goldberg]

Builders using the SPRL have the fuel come out the front and then the lines go aft to the gascolator. I used a 45 fitting out of the front.

Also, I have not seem (or maybe didn't notice) bad quality on the SPRL. Have never had a problem with them either. Mark

[Ed.Meyer]

Saw this the other day regarding water at low point and gascolator placement: http://www.vansairforce.com/communit...d.php?t=135910. Seems that there is considerable difference of opinion on the need for the gascolator to be at the low point. Regarding the SPRL valve, if using the one that handles fuel feed and return,for injection systems needing return lines, it was not intuitive to me which part of the valve is for the feed and which the return. Had to re-plumb after finding out it was wrong.

[Ed.Meyer]

The machine work on ours was real good and has smooth operation.

[lsa140]

My observation is that when you mount the gascolator at the low point it becomes a sump for the entire fuel system when parked. (passive) When fuel is circulating through it in flight it is active. Sure you could mount it on a 9' pole above the plane, but it would only function in its active role. Having it located at the low point allows one device to serve two purposes.

As Battson pointed out, water would collect against the fuel selector valve on the Bearhawk when it is parked and shut off. With the selector valve outlet forward, water wouldn't travel to the gascolator unless you drained enough fuel before starting, or started the engine. I like the installation Bob shows in the LSA book. The gascolator is plumbed directly on the fuel valve, strait behind it. The question is how fast does collected water flow through a small fuel line when the valve was open, and the engine off.

I'd like to install the gascolator plumbed strait back from the fuel valve. You could make setting the fuel to both one of the first items you did during pre flight, and draining the gascolator one of the last.

I calculated the bowl volume of the Bearhawk gascolator to be around .02 gallons. At 8 gph flow through the gascolator is .133 gallons per minuet and .0022 gallons per second. So at 8 gph the Bearhawk gascolator bowl capacity is being exchanged every 9 seconds.

[French]

↵I used the SPRL valve. Installed it 180 degrees off, drain port to the tail, downhill. Re-drilled the face place with three new holes (under the valve knob) to line up with the original valve holes, so the markings are correct. Was able to drill it by hand. Used a countersink bit on the new holes. Installed a wooden disk spacer under the valve to get the elevation correct with the floorboards. Spray pained it with crackle aluminum, so it is a close color match. Didn't do any mods on the valve itself so it should be fine. Quality on my valve was perfect. So good, I really hated to hand drill it, but it worked. Can't tell of any changes when it's all put together. Tried to upload two photos, but the system must have choked on them. Will try again if any one is interested.

[French]

Here are some pics.

[whee]

Maybe I'm not fully understanding what you did French. If all you did was rotate the valve 180* and drill the face plate so it stayed in its original orientation then wouldn't it be labeled wrong? Off would be both, Left would be right etc?

[French]

SORRY ! Yes. I should have looked at my parts box before I sent the pics. It's been a few years since I messed with it. You do have to re-do the OFF and BOTH, they are backwards. I had cut several new face plates to overlay the old one, but have not installed them yet. Decided to have an engraver cut my overlays. It was a bit of a hassle the more I recall, but my valve is real nice quality, so I can't complain. You all may have better luck, but I never found a valve as nice as this one.

[whee]

New valve arrived today. Machine work is just as bad but it operates smoothly. I'll keep it, deburr the ports and make sure I put plenty of thread sealant on the 1/4" NPT fittings.

I kinda like what French did so might see if I can get an overlay made that looks nice so I can do the same.