ORIGINAL: ptuxbury

Hello,

I'm a relative beginner, so I have a few questions regarding mounting an engine behind a cowl.

I'm currently building a Graupner Extra 300S with a Super Tigre 90. This is my first plane with an engine cowl. I had to buy a Slimline Pitts muffler in order to fit it behind the cowl. I cut clearance around the engine head, muffler, etc, but even then, it's still pretty difficult to put the cowl on. I have a few questions regarding the engine/cowl installation:

1. How do I fill up the fuel tank? In my other planes, I remove the fuel line from the muffler and the carb. I fill through the carb until it starts to come out the muffler line. I don't see how I'll be able to get to either of these lines with the cowl on, so how do I fill (maybe a 3rd line), and how do I know the tank is full?

>The 2 ways most people use most often is a fueling "valve" and 3rd line.
>My experience with the fueling valves has not been good. I have not had
>one make it a season without leaking. I use the 3rd line method with 2
>clunks in the tank. Most people wait until they see some fuel come out of
>the muffler, then they know the tank is full.


2. Is it unusual to have to remove landing gear to be able to fit the cowl on the plane? The instructions mentioned to cut 4 holes in the cowl for attaching the landing gear screws. I didn't realize why until I tried to put the cowl on with the landing gear still mounted. It seems like the only way to fit the cowl without cutting out large pieces of it is to remove the landing gear, put the cowl on, and then re-attach the landing gear.

>That does sound unusual to me, however I am not familiar with your
>plane. I suggest cutting the cowl to fit over/around the landing gear.


3. How often do people generally take the cowl off once it's mounted? With my current plane I clean around the engine / engine mount pretty often. If a cowl screws onto the plane, then how can I clean around the engine? Do I just fly it 10 times before removing the cowl to clean?

>I normally leave the cowl off and fly the plane several times so that
>I can fine tune the engine (if needed). Once the engine is fine tuned
>(low end) I put the cowl on. As for cleaning, the inside of the cowl
>USUALLY stays relatively clean. The outside I clean with Windex.
>
>As a side note - To prevent/minimize overheating of the engine you
>should have a 3:1 ratio for cooling. For every 1 square inch of air inlet
>you should have 3" square inches of air outlet.

I think that pretty much covers it. Any help would be appreciated.

Thanks,
Patrick