FI return line

tshort · Post by **tshort** » Fri Jun 16, 2006 3:50 am

Anyone see any problem putting the return line in the upper aft area of the inboard rib (sort of in the "triangle" formed by the access plate, the top of the rib, and the aft edge of the rib)?

Thomas

captain_john · Post by **captain_john** » Fri Jun 16, 2006 6:09 am

Well, nope...

It sounds as good a place as any, I suppose.

I suppose if there was one gripe I would make is that it would be only slightly harder to install the access plate with it in the way.

CJ

tshort · Post by **tshort** » Fri Jun 16, 2006 7:06 am

I think it will be OK if I put it far enough away from the access plate; problem is I drilled the other holes in the rib (vent and BNC connector) before I planned the return line and with the flopper in the L tank there is no place on the forward part of the rib...

T.

captain_john · Post by **captain_john** » Fri Jun 16, 2006 8:33 am

Whoa, whoa, whoa... hold the phone!

Whatta bout the baffle to rib rivets. You know, the -4's!

Those can be a bear to set!

I think that could be a showstopper!

Check it out.

CJ

cjensen · Post by **cjensen** » Fri Jun 16, 2006 9:33 am

Thomas,
Can you post pics of where you want to put it? I'm having trouble figuring out the "triangle" in my head.

Are you returning to the first (inboard) bay?

tshort · Post by **tshort** » Fri Jun 16, 2006 9:57 am

Baffle to rib rivets ... can't I squeeze those?

I'm at work and don't have a pic ... here is a pirated one:

It would be in the bottom right corner of the rib as viewed in the picture.

Thomas

cjensen · Post by **cjensen** » Fri Jun 16, 2006 10:01 am

Okay, I understand now.

What about the location of the open end? Is it going to flow back in to the first bay, or go farther into the tank?

I'm curious, because I may go ahead and install a return line, and just cap it off if I do go carb'd. If it can be returned to the first bay, that's easy! Otherwise, I have several holes to drill in to each rib, which have already been riveted in place.

tshort · Post by **tshort** » Fri Jun 16, 2006 10:30 am

I'm not sure what you mean by the open end?

I don't see any reason not to return it to the first bay - others have mentioned possibly going in a couple to allow some cooling and maybe decrease splash / foaming but that's probably not a huge deal (altho I'm not an expert on this)

The carb is an interesting thought. My skyhawk has an injected engine; it runs great, but is a bear to hot start. The 170, which is carbed, starts on the first blade every time regardless of temp. I'm leaning toward injected but haven't decided for sure yet...

Thomas

p.s. it looks like you're working as hard as me at work today!

cjensen · Post by **cjensen** » Fri Jun 16, 2006 10:40 am

Yeah, working hard...that's right...Uh, let me see here, what can I work on...

Anyway, back to what matters...the return line- By open end, I just mean the end of the tube that will dump the fuel back in to the tank. Sorry 'bout the confusion. I knew what I meant!

The only issue I could think of is cooling as well. Hadn't given splash or foaming a thought. But, how warm is the fuel gonna be when it comes back? It's gonna cool as soon as it hits the pool in whichever bay it goes back to.

Yeah, hot starts with an injected engine are a PITA!! My Cherokee did the same thing. It would start the same everytime, regardless of when it was shut down.

Plus, with FI, you have a high $$$ fuel valve and an even higher $$$ high pressure fuel pump. I still may go FI, but am leaning carb'd right now. That's why I think I'll put the return line in, and just cap it off if it's not gonna be used.

captain_john · Post by **captain_john** » Fri Jun 16, 2006 1:34 pm

Thomas, Yah...

You MIGHT be able to squeeze those. Some of mine, I could. The problem for me was the cupped set was a bit too large in diameter and the rib pushed the cup off the rivet head which ended in a less than desirable end product.

I ended up hammering them. In that case, you would need a bucking bar there! If there was a fitting there, plan "B" would be not an option.

Hope this helps!

CJ

tshort · Post by **tshort** » Fri Jun 16, 2006 2:14 pm

Why not put the manufactured head on the other side? Then you could (theoretically) squeeze them with a thin nose yoke... ?

Thomas

captain_john · Post by **captain_john** » Fri Jun 16, 2006 3:04 pm

Assemble it and try it. Do a dry fit and see if you can reach them. Remember, the Z-Bracket gets in the way too!

CJ

tshort · Post by **tshort** » Fri Jun 16, 2006 3:06 pm

Hmmmmmm
Didn't think of that. I'm not in the shop and can't picture which way the Z-bracket is oriented there... but I think it is the "wrong" way!

T.

captain_john · Post by **captain_john** » Fri Jun 16, 2006 3:31 pm

Yah, that and the skin on the other side sticking up gets in the way of the body of the squeezer.

Lemme know how you make out!

CJ