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How To Get This Pipe Into That Hose?

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VF84Sluggo

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And now, for the next episode of my ongoing Sky Dynamics cold-air induction system intake leak saga... :)

I get to the "install new hose segment" part...and now, how in the world to get this slightly flared tube end into the hose segment? It slips over the plenum end just fine.
 

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Maybe try using one or two plastic tire irons that one would normally be used for changing a bicycle tire? Just a thought.
 
Put the rubber sleeve in boiling water for a few minutes.....

You're welcome!

-Marc

Man...I boiled, and boiled again, and again, as long as 5 minutes...and these hose pieces will NOT give enough to get over that flared part of that induction tube. Man....
 
Reinforced hoses

The fiber wrapping reinforcement isn’t going to stretch or get pliable like the rubber..
Possibly slowly using a swedging tool. Try a piece first to make sure you don’t break the fibers..
 
Haven’t tried it on these/don’t know the amount of interference, however:

Dry ice is ~ -100F. Chilling acetone to equilibrium with it will make the heat xfer very effective; enough to shrink the metal appreciably.

It’s effective for metal/metal interference fits. Should work here. Work fast.

If you try it use caution as it’s both flammable and will (cold) blister you.
 
According to the Sky Dynamics installation instructions these joints are sealed with an internal silicone o-ring and not an external rubber tube and clamp setup. Probably why they don’t fit.
 
Yes, looks that way.

But, I have emailed and called SD a handful of times in the last week, email and phone call today, asking - no, begging - for help: nothing. No response. Totally NORDO on me.

I'll figure something out.
 
It is clear that your tubes don't have the internal o-ring.

I would either (or both) get an exhaust tubing expander and use some talc (talc is the best lubricant for rubber) or get a hose that is not so stiff. Since the tubes nest, the hose is not so important for pressure just to seal a small suction leak and allow some axial float. No reinforcement would be required.

Depending on the reinforcement it might shrink with elevated temperature.:eek:

Screen Shot 2022-10-25 at 4.41.46 PM.png
 
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Some engine set ups use a larger hose going over the smaller diameter hose such that the smaller hose is used as a "shim" to get the diameter up to the ID of the larger. Continental A65,C85,C90 & O-200's are one example.
 
Silicone spray.

Worth a try.

I'm not the builder, didn't install this Sky Dynamics cold-air induction system, so all I have to go on is how it's installed in the plane. Don't know if this is the original install, or has been worked on, but there were gaskets in addition to o-rings at the cylinder flange. And, hoses/clamps at the manifold stub pipe/intake pipe junction.

Neither seems to be how the system is supposed to be. O-rings only, both at the flange and at the pipe/manifold junction. SD has been pretty much unresponsive.

Kind of on my own here. I did solve (I hope) the flange o-ring/gasket nonsense. The thickness of the o-rings as installed were too small, not making a seal. Perhaps that's why someone added gaskets. Who knows. But I found thicker o-rings today that were a drop-in fit, preliminary soapy water leak test look good. Keeping my fingers crossed on this!
 
Tube and hose fitting

I did not believe this till I tried it. Wet the rubber with rubbing alcohol, liberally. It will slide slicker than snot on a doorknob.
 
And now, for the next episode of my ongoing Sky Dynamics cold-air induction system intake leak saga... :)

I get to the "install new hose segment" part...and now, how in the world to get this slightly flared tube end into the hose segment? It slips over the plenum end just fine.

Try installing the intake tube without the hose. Each tube is numbered for the correct cylinder. The intake tube should have a bead formed near the end to hold the O ring.
 
Try installing the intake tube without the hose. Each tube is numbered for the correct cylinder. The intake tube should have a bead formed near the end to hold the O ring.

Ok. Problem is, I have no idea what o-ring goes inside the pipe/manifold stub junction. And I don't recall seeing a bead on any of the numbered pipes, or a 'seat' inside the manifold stubs.

Now, the best I can tell is that this SD cold-air system was installed by the Sorrell folks back in Feb 2006. From the ONE time I actually got someone from Sky Dynamics on the phone, it sounds like there have been subsequent versions. For sure the pic they show of the 4-cyl Lycoming kit does NOT match the installation instructions you can pull up on their website. The single sheet of installation instructions I found in my paperwork that I got with the plane does not match SD's online instructions, either.

In just one example, in the kit pic on their website you'll see these truss-like brackets that go from the sump/engine to the fuel servo for support. In the instructions on their website you'll see the truss/tubes are gone, and a bolted flange-bracket does the supporting (much better, IMO...these truss/tubes SUCK!)

I'll end up just solving this mess on my own. I no longer expect a THING from Sky Dynamics.

1st pic: Website 4-cyl kit; 2nd pic: Website 4-cyl install instructions
 

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What is the actual OD measurements of the intake tube & plenum tube flanges?

Most Lycomings intake tubes are 1 3/4" OD, obviously won't work for you.

O320-H2AD intake has a stepped hose that joins the tube to the oil pan/plenum, the tube OD is 1 3/4" & the plenum is slightly larger (sorry, couldn't get an OD measurement), the hose pt# is LW-18101 for the H2AD.
Possibly that might work for you.

Note- although some radiator hoses have diameter bulges that might fit - do not try as those hoses are not compatible with fuels & will degrade quickly, than you would have a bigger problem...

"gasman
You could try this on the hose and see how it effects the hose..... https://www.harborfreight.com/medium...der-57707.html
Do you still have the hose that was removed? You may see how it was installed."

Or you could take the tubes to a car exhaust shop & see if they could shrink the intake tube diameter as another possible option
 
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O320-H2AD intake has a stepped hose that joins the tube to the oil pan/plenum, the tube OD is 1 3/4" & the plenum is slightly larger (sorry, couldn't get an OD measurement), the hose pt# is LW-18101 for the H2AD.
Possibly that might work for you.
Yes, that might work...but at anywhere from $70 to $95 per hose...yikes!!!
 
Before you jump at the LW-18101 hoses, get someone to measure the intake hose flange diameters on a H2AD oil pan....

& what's $70 (x4) to an airplane fanatic? I thought everything on the plane started at $50 & goes up!
 
Well, the guy at the aviation aisle at O'Reilly Auto Parts solved my hose/pipe hassle. He initially suggested a radiator hose, but thanks to Ralph Inkster I knew that would be bad juju.
He then suggested I try the local industrial hose, rubber, gasket company.

I went there. In their aviation aisle, they had 1 3/4" ID fuel/hydraulic hose that would give just enough to slip over the flared (slightly larger than 1 3/4" ID) end of the intake riser pipes.

AND! it was only $12.50 / foot. Had I known this, I'd have never wasted the $7.50/section of the Lycoming/Superior hose sections.

Anyway, looks like the problem is solved....I hope :D
 
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