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-   -   The Terrifying Tale of FrankenSnorkel ! (https://vansairforce.net/community/showthread.php?t=118549)

scrollF4 10-13-2014 08:21 PM

The Terrifying Tale of FrankenSnorkel !
 
<<WARNING: NOT FOR THE FAINT OF HEART OR STOMACH>>

Just in time for Halloween, let me tell you the chilling tale of a poor tortured FAB snorkel, one like so many others, that began its life as one whole and complete fiberglass item with dreams of living in a mighty fire-breathing 200hp IO-360. However, as (mis)fortune would have it, this snorkel ended up in a 180hp IO-360 firewall forward kit.

Again, like so many others, its kitbuilder saw need to dismember the snorkel horribly into two separate end pieces:



The snorkel's dismembered limbs were drawn to separate locals, then bolted under high tension to horrible machines of torture with names like fuel injection servo and intake ramp. Oh, the horror:



Then, the kitbuilder mutilated the poor snorkel to cram its mangled body into the most agonizingly tight spaces:



Oh, the horror...



Hideous metallic probes and studs were riveted to the snorkel's neck, like electrodes on a Hollywood monster:



When the mad kitbuilder was satisfied with his sadistic placement of the snorkel's two limbs, he hideously grafted them to the center part he had surgically removed before, transforming the once-beautiful fiberglass snorkel into.....FRANKENSNORKEL!!! :eek:




The mad kitbuilder wrapped poor Frankensnorkel in layer upon layer of rotting, festering, skin, making the monster even more monstrous:



....to be continued in episode 2....

scrollF4 10-13-2014 08:21 PM

Episode 2
 
He then clothed Frankensnorkel in the brightest ghost-white clothing, hiding the horror that lies just beneath the rotting skin:



And now, doomed to a life of torture under the cowl of an otherwise beautiful RV-7A, one can find the desperate gasps of the pitiful...
the wretched...


(wait for it)


FRANKENSNORKEL!! :eek:


Neal@F14 10-13-2014 08:52 PM

At least a portion of the tale is somewhat riveting.

longranger 10-13-2014 10:52 PM

I'm just hoping that someone comes out with one that "just fits" before I get to that point...

RKellogg 10-14-2014 04:10 AM

Cowl clearance??
 
Scroll, are you sure that your snorkel will clear the cowl? I thought mine was done when I was at that stage, but wound up visiting the bandsaw and belt sander again for further 'slim and trim'. After a while I started saving "spare" pieces...



- Roger

scrollF4 10-14-2014 04:47 AM

So far, so good.

Danny King 10-14-2014 07:16 AM

FrankenSnorkel
 
That sure is a terrifying tale. But I'm spooked as to why all that was necessary.
I've done four snorkels. One for the Doll, and three for other builders, and non of that was necessary! Are you sure you started with the correct snorkel? I wouldn't bet my life on it, but I believe there are two models.

I start by fitting the left baffling to the engine. Then I remove the front baffle piece that the snorkel fit to. Then I clamp the snorkel's flange to the throttle body, and swing the snorkel up until it just about hits the starter. Using the angles that attach the front baffle to the engine, I trace a cutting line on each side of the snorkel at the proper height and slope so as to match the front baffle. When I cut the snorkel, I add enough length to the cut to allow for the K&N filter to fit. Then I install the front baffle and cleco the snorkel to it using the mounting angles. Now you can see exactly where to cut the square hole in the front baffle, but I don't do that until the next step is complete.

(Note: I rivet a .040 doubler to the front baffle, and use the rubber seal of the K&N filter to make the seal with the baffle instead of using the filter mounting hardware. If you plan to use the mounting hardware the snorkel is not cut shorter to allow for the filter)

I cut off the snorkel's mounting flange at the throttle body. That angle is never quite right! With the mounting flange drilled and bolted to the throttle body, I glass the snorkel back to the flange at the correct angle.

The only cutting done to the snorkel is at the mounting flange, and to the other end to match it to the front baffle. There is nothing that horrifying about it!

As to cowling clearance.....it is very tight. It is important that the gap between the spinner back plate and front of the cowling be kept to a minimum!

The Doll has to places where the inside of the lower cowling contacts the snorkel during high G flight. I used a couple pieces of the nylon material Van supplies for the flaps to wear against the wing to insulate the contact points with the cowling.

rzbill 10-14-2014 09:24 AM

Danny,
Your sig file says angle valve motor. The OPs is a parallel. They are different widths.

While I imagine one can install the snorkel on a parallel valve without cutting it, its my opinion that the filter sits to far outboard and it affects the outboard baffle position negatively where it interfaces with the cowl.

RKellogg 10-14-2014 10:01 AM

FAB rework
 
I think my extreme snorkel rework was due to the cold induction manifold & adapter pushing the fuel servo farther forward... Many possible combinations.
- Roger

Paul K 10-14-2014 10:35 AM

Scroll, I feel your pain!

I used an IO360 with ECI cold air induction and the fit wasn't even close! I,m talking off by more than 1 inch on the inside and 3 inches on the outside plus it made contact with the starter flange and the alternator. I started out doing what you did to make it fit but was so totally turned off by the results that I tossed it in the junk and built one from scratch. Not that hard to do and ended up looking better than I dreamed it could! Give it some thought and feel free to call me with questions. It can be done!







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