Extended breather line to tail: has anyone done this?

[F1Boss]

Originally Posted by Gash

So....what I've decided to try is running a breather line to the tail on the outside of the aircraft along the centerline of the belly, all the way back to the tail. I'm thinking about using rivnuts and clamps to hold the tube in place.

Any comments on this idea?

If you're gonna go to that trouble, why not try running it down the aft edge of the gear leg 1st as an experiment? Duct tape could be used for this quick 15min flight...might add some tie wraps over the tape in case things get warm..

Terminate the line near the axle with a curve to put the outlet 2-4" away from the wheel pant. If it works (doesn't dump oil on the empennage), you could add an interior line w/connector to the pant to put the outlet at the aft end of the pant, kinda like the fuel tank vents on a B-25.

Your Plan A would also work, but it's gonna generate plenty of remarks..

Carry on!
Mark

[Gash]

Originally Posted by JonJay

Sounds like a lot of work just for the sake of a few pints of oil and a clean belly for your occasional aerobatics Gash.

I know what you mean JonJay, but I don't fly occasional aerobatics . I actually fly aerobatics once a day, sometimes twice a day. Each time I go up I run through the IAC Sportsman sequence at least four times per flight. I am spitting out an amazing amount of oil on my belly. All the time wasted wiping up oil afterwards is getting out of control. They say "necessity is the mother of invention" and my little invention brain is revving up!

[Gash]

Originally Posted by F1Boss

If you're gonna go to that trouble, why not try running it down the aft edge of the gear leg 1st as an experiment?

Mark, I think that's a cool idea. I have the airfoil Grove gear legs, so I'm not sure how well that would work to put a 3/4" or 5/8" tube on the trailing edge of the gear. It might be better than a full-length belly tube though. I gotta think about this one. Thanks.

[Krynn]

Why not run it into your exhaust like you had it before, and put a tee with a 0.25psi pop-off valve to an emergency line that will dump it on your belly in case the exhaust tap gets blocked? (Yes, I'm looking at the Anti Splat Aero Crankcase Vacuum Kit Complete right now )

[JonJay]

Originally Posted by Gash

I know what you mean JonJay, but I don't fly occasional aerobatics . I actually fly aerobatics once a day, sometimes twice a day. Each time I go up I run through the IAC Sportsman sequence at least four times per flight. I am spitting out an amazing amount of oil on my belly. All the time wasted wiping up oil afterwards is getting out of control. They say "necessity is the mother of invention" and my little invention brain is revving up!

Sorry for assuming. That's a lot of aero!

[Gash]

Originally Posted by Krynn

Why not run it into your exhaust like you had it before, and put a tee with a 0.25psi pop-off valve to an emergency line that will dump it on your belly in case the exhaust tap gets blocked?

I thought about that Krynn, but I have such a high volume of oil going overboard (about 1/2 quart per flight) that I'm worried about the fitting getting blocked by cooked oil, and then the pop off valve getting sloshed with oil and failing.

[Gash]

Originally Posted by JonJay

Sorry for assuming. That's a lot of aero!

Hey no problem! I know it's out of the ordinary to fly so much aerobatics...I'm just trying to make sure I don't make a darn fool out of myself when I go to the first IAC contest this year!

[F1Boss]

Originally Posted by Gash

Mark, I think that's a cool idea. I have the airfoil Grove gear legs, so I'm not sure how well that would work to put a 3/4" or 5/8" tube on the trailing edge of the gear. It might be better than a full-length belly tube though. I gotta think about this one. Thanks.

Put it on the front....less drag there. I'll bet a 1/2" line would work fine, unless your engine has LOT of blow-by. Heck, it's only an experiment unless it works!

Carry on!
Mark

[Gash]

Originally Posted by F1Boss

Put it on the front....less drag there. I'll bet a 1/2" line would work fine, unless your engine has LOT of blow-by. Heck, it's only an experiment unless it works!

Good thinking Mark. Leading edge makes sense, and yes, 1/2" is plenty big for this application. Next problem is figuring out how to get the radius bends to work right in 1/2" line. I'll need two 90 degree bends. I thought about using rubber hose at the bends, but can't risk having the hose collapse.

[F1Boss]

Originally Posted by Gash

Good thinking Mark. Leading edge makes sense, and yes, 1/2" is plenty big for this application. Next problem is figuring out how to get the radius bends to work right in 1/2" line. I'll need two 90 degree bends. I thought about using rubber hose at the bends, but can't risk having the hose collapse.

I'm running 1/2" fuel lines on my current build - the bender I have can roll the 1/2" tube in a ~2" radius. I'll bet you can borrow one like it....

Carry on!
Mark