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For those that have an AeroVee with an AeroInjector, but no gas collator, do you have a drain valve? Right now I don't. The carburetor is the low point. The DAR is asking why I don't have one, and it seems like a good question since how would you check for water or contaminants with the carb and fuel lines inside the cowl/ Then again, how do you install and reach a drain valve when the carburetor is the low point in the system?

Mike Smith
#439

Mike,
Like yours, my plane has no gascolator or drain valve, the carb is the low point in the fuel system. I do have a fuel filter. I'm not concerned about this setup--if there's water in there, I'll know about it long before I finish my taxi to the runway.

I think the concern isn't water, but dirt or other contaminants. I have found strange looking things in my gascolator on occasion. The assumption is that the fuel filter will stop the contaminates without itself being stopped up, so at least the fuel filter has to be checked, cleaned or replaced at intervals.

radfordc wrote:I think the concern isn't water, but dirt or other contaminants. I have found strange looking things in my gascolator on occasion. The assumption is that the fuel filter will stop the contaminates without itself being stopped up, so at least the fuel filter has to be checked, cleaned or replaced at intervals.

Yes, but that apparently isn't the way the DAR sees it. His point is you want to check for these before every flight.

Mike

Yes, but that apparently isn't the way the DAR sees it. His point is you want to check for these before every flight.

Shame on me perhaps, but I agree with the thinking of the DAR. If it wasn't for the design of the Aerocarb with the burps that it is famous for, the thought of deleting the gascolator would be considered absurd. I suggest that the source of the concern is not the gascolator and as such should not be the part that is left in the hangar.

My $00.02 and worth as much as it costs ...

Dale
N319WF

daleandee wrote:

Yes, but that apparently isn't the way the DAR sees it. His point is you want to check for these before every flight.

Shame on me perhaps, but I agree with the thinking of the DAR. If it wasn't for the design of the Aerocarb with the burps that it is famous for, the thought of deleting the gascolator would be considered absurd. I suggest that the source of the concern is not the gascolator and as such should not be the part that is left in the hangar.

My $00.02 and worth as much as it costs ...

Dale
N319WF

I personally don't see the need for a gascolator for an AeroInjector, but as far as the fuel drain, I also agree with the DAR. However, with the design of a Sonex/AeroVee, with a strictly gravity-fed, updraft carburetor, how do you install a drain valve? You don't want the valve below the carburetor, so you can't install it at the bottom of the cowl. Besides, the hot exhaust is down there, so you don't want the fuel line close to it. If you install it in-line in front of the firewall, how do you reach it without removing the cowl? And even if you did, what kind would you install? The ones I've found need to attach through something flat and rigid like a cowl or firewall.

Mike Smith
#439

Just digging up this thread again. I would like run my fuel lines with a filter and without a gascolator but I feel my inspector will be wanting to see a drain valve. I am not concerned about just running a filter as clearly this works well. From the gascolator survey b4 it would seem most people run gascolators regardless of the issues they may or may not cause. I am at the stage now where I need to make the decision. My other plane ( high wing) I ran a gascolator and rotec tbi after having major issues. However as I have an aerocarb sitting on the shelf I would like to give it one more go on a Sonex before I reluctantly fork out $1200 or so. To be fair as well I want to give it an honest best chance to prove me wrong.

On a slightly different note, while digging through the net for info on all this I came across a post about aerobatics in the Sonex and that if the aircraft did have a gascolator whilst momentarily inverted the engine won't quit as it has a foot or so of fuel in the line to keep it running. I can't recall where I found this but was wondering if this really is the case?

Thanks in advance and soz for all my questions lately but the help is really appreciated.

For what it is worth. I too considered building and/or removing the gascolator. I did not remove it as I wanted to wait and see if I had the old heat issues. As it turned out I did have some burps. At that point I consider removing the gascolator but I did not feel comfortable about not being able to check the fuel from a large bowl with a screen. So I went and did the reduce heat method as can be seen in the Sonex 1534 photos post. I did fly a couple hours yesterday. The second long flight since I made the changes. The burping is gone. I felt very confident about the fix. Just my 2 cents on what I did.

I just have a filter without a gasolator, the inspector didn't say anything at all about it.

I took the plunge and just ordered the recommended gascolator last night from spruce. Ah well, I'm sure it will all be good.