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SDS No More Leak Induction Tube Solution

Ok gents, I picked up the flanges from the anodizer this afternoon so can start shipping tomorrow. I'll contact those on the list first who've spoken for a set.

Thank you to everyone for your support and being patient.

Great! I'm looking forward to ruling out one more potential area for intake leaks.

-Marc
 
Flanges 'r Us



We started shipping orders today and will ship some more tomorrow. Still waiting on some larger CT clamps for the carb hoses. Will see some late next week I hope and some more to follow so right now, we can only fill the FI orders using the smaller OD silicone hoses.
 
I got some clamps in for the carb hoses yesterday but all sold out again now. I just ordered some more, cleaning out the supplier. Ditto on the 1.75 silicone hose. These should be here Monday if lucky and I can fill the rest of the orders. Sorry for the delays. I had not anticipated this sort of demand.
 
Hi Michael,

After I installed the flange around the intake tube, I placed the O-ring in first, and then the retaining metal ring on top of the o-ring. I then pushed down on the metal ring to make it flush with the top of the flange and o-ring.

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This made installation pretty easy, as it all wanted to stay together.

Got my parts last week and installed a couple on the Rocket today. I tried Mike's method above (well, similar) as well as "my" original method to compare. First off, either one is comically easy to do on a straight tube, parallel valve. Hard to complain about one method being "harder" when at worst, it's less than a 5 minute job per tube. That said, I think Mike's method of pre loading the seal assembly into the retainer and tube, then bolting the whole thing to the head is the best way to go. This is opposed to hanging the tube/retainer by the two bolts THEN slipping the O ring assembly into the gap. The one caveat to this is that I load the o ring onto the inner retainer (looks like a little mototcycle tire) and drop this into the tube retainer (or slip it into the gap). The inner retainer (or "rim" if you prefer) has a concave groove cut which holds the O ring pretty securely (like a tire).

At any rate, its just easy, easy, easy, and I expect this is the end of the age induced induction leaks.
 
Good pix Mike. Thanks for posting.

We are getting a lot of feedback from users saying their EGTs have evened up in cruise, idle is smoother etc. Some people must have had some truly massive leaks before. I could see the idle/ part throttle improvements perhaps but it's hard to believe there could be such a change in cruise at near WOT where there is little delta P between the inside and outside of the joint.

Anyway, we're happy they work so well. Continuing to ship more this week as our other parts come in.

Thanks to everyone for your orders and feedback.
 
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Received some of the big CT clamps for the carbed engines late yesterday. Will ship a few of those outstanding orders today.

Another run of flanges will be CNC'd later this week.
 
Looked on the web site but couldn't find a way to order a set.
Could you put me on the list for a set? Gold flanges, IO-320 E2D.

PM me if you need any other info.
 
To all those who've placed orders, I haven't forgotten about you. We're shipping sets as fast as we can given the large backlog of these and CPIs/ EM-5s.

Summertime is often a slower time for us. Not this year. Thanks to all for keeping us hopping!
 
To all those who've placed orders, I haven't forgotten about you. We're shipping sets as fast as we can given the large backlog of these and CPIs/ EM-5s.

Summertime is often a slower time for us. Not this year. Thanks to all for keeping us hopping!

How do we order? Sent a PM.
 
I want in on a set.

I would like to get in on a set for my IO-320 Ross. I sent you an email.
Dave
 
I have a few hours on the prototype set now and after some long cross country time in record breaking desert heat I decided to pull the cowl and inspect. I removed a tube, washed the O-ring in soap and water and gave it a good look. Essentially, it looked new, as did the other parts - so I put it back together. Nothing to see here - as expected. Good product.

Hey Ross, I have 5 other people headed your way - each for a set. Hope your machine shop can keep up!
 
I have a few hours on the prototype set now and after some long cross country time in record breaking desert heat I decided to pull the cowl and inspect. I removed a tube, washed the O-ring in soap and water and gave it a good look. Essentially, it looked new, as did the other parts - so I put it back together. Nothing to see here - as expected. Good product.

Hey Ross, I have 5 other people headed your way - each for a set. Hope your machine shop can keep up!

Thanks for the report Mike.

We have another batch scheduled to run before Aug. 20 and at this point have scheduled recurring runs every month until (or if) demand starts to taper off.

We appreciate all the VAF orders and are shipping sets every day trying to keep up with demand.
 
This may be a far out question, but does anyone have an idea of what it would take to get a one-time 337 approval for a certified plane?

If the temperature specs on all of the parts are similar to the Lycoming paper gasket, it sounds almost like a minor change.
 
Suggestion for those with larger intake tubes.

Rather than having to cut and weld, split the new flange similar to the way the plastic spark-plug wire pass-through works in the rear baffles.
 
This may be a far out question, but does anyone have an idea of what it would take to get a one-time 337 approval for a certified plane?

If the temperature specs on all of the parts are similar to the Lycoming paper gasket, it sounds almost like a minor change.

We've looked into the STC and PMA processes a bit and it's looks pretty involved satisfying the letter of the law even on such simple parts as this. It comes down to vetting and tracking of the materials and manufacturing process of each part plus testing to validate performance on the PMA stuff.

Even in quantities of thousands, I wouldn't be surprised if it tripled the price of these to comply. As we only make the flange and not the other OTS parts in the kit, it doesn't seem to be worth it for a small company like us to jump through all the hoops and create that paper trail.

Now if someone else wanted to do all the work to get an STC approved, we could supply the parts...
 
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We've looked into the STC and PMA processes a bit and it's looks pretty involved satisfying the letter of the law even on such simple parts as this. It comes down to vetting and tracking of the materials and manufacturing process of each part plus testing to validate performance on the PMA stuff.

Even in quantities of thousands, I wouldn't be surprised if it tripled the price of these to comply. As we only make the flange and not the other OTS parts in the kit, it doesn't seem to be worth it for a small company like us to jump through all the hoops and create that paper trail.

Now if someone else wanted to do all the work to get an STC approved, we could supply the parts...

My question was for a one-off 337 field approval, not a full STC. :)
 
The best bet would be to find a "sympathetic" party to get the first 337 approved, thereby creating the supporting data for the rest to follow. I understand it's hard to get the first one to stick their neck out these days however.
 
Next batch

G?day Ross,

When are you taking orders for the next batch?

Wouldn?t mind a set for io-320 & o-360
 
G?day Ross,

When are you taking orders for the next batch?

Wouldn?t mind a set for io-320 & o-360

We take orders continuously and put folks on a waiting list. I just doubled the next run quantities which should be in hand mid August.

Still shipping orders on what we have left in stock to those previously on the list.

I'll add your name.

Thank you.
 
I ordered a kit for my IO540 as I always suspected an intake leak on my engine. I had already replaced all of the flat gaskets, but the idle was still not as steady as it should be. While doing the install, I found that at least one of the flat gaskets (and maybe two) were leaking.

It turned out that the intake tubes, which are connected to the plenum with rubber hoses, just didn't line up with the stub-outs on the plenum, This caused the stiff rubber hose connectors to exert too mush pressure on the tubes, which in turn caused the flat gaskets to leak. My number 1 intake tube was 7/I6" lower than the stub out it was connected to! It was impossible to use the o-ring replacement from Ross without correcting the tube alignment.

I've ordered new parts from Barrett and will have them custom TIG welded when they arrive. If you plan to use these on a 540 they are difficult to install. If you have a cold-air induction system make sure the tubes line up with the plenum first.

-Marc
 
I received another order of green silicone hose for the injected engines today and have red flanges in stock. Anyone with an injected engine who wants red flanges with green hose, drop me a PM or email and we can ship this week.

I expect the clamps for the carbed engines tomorrow and we can start shipping red flanges for carbed engines then.
 
Have red flanges, CT clamps and hoses in stock now for carbed engines. I've contacted most people on the "list" now. If I've missed you somehow, drop me a PM. Thanks.
 
For those who don't know Ross' work ethic, I received a call from him Saturday afternoon to say the parts were available. How many vendors will call you on a Saturday afternoon?!?!

Sorry I wasn't able to answer the phone, Ross. Was being vectored around north of Montreal and had my hands full with an on-the-fly low level re-route.
 
I was at the shop Sunday too but at least I got a short flight in despite the heavy smoke around here.

For folks phoning us, we are on Mountain time and I'm usually in the shop before 0630 but often have to leave around 1400 to run parts pickup and delivery errands in the city. I like to avoid the rush hour traffic which begins around 1500 here.
 
Too much to hope that someone would design a "take-apart" solution so that no welding is required? Now that would be truly awesome. :)
 
Spare O-Rings?

Ross, loving my induction setup! if a guy wanted to source a couple spare O-rings to keep in the spare parts kit (non-silicone for me - carb engine), is this a common size? Or should I call you for some spares?
 
Ross, loving my induction setup! if a guy wanted to source a couple spare O-rings to keep in the spare parts kit (non-silicone for me - carb engine), is this a common size? Or should I call you for some spares?

Glad you like them. We have received tremendously positive feedback on how these cure many running problems and we're happy to hear that. Some folks have some really serious popping and rough running with the paper gaskets and stock flange setups. These seem to cure those leak induced issues entirely.

We purposely chose off the shelf O-rings so people can source locally. These are #135 Viton, 70 or 75 durometer. For the injected folks, they can also run these or get silicone ones in the same size and durometer range.
 
Too much to hope that someone would design a "take-apart" solution so that no welding is required? Now that would be truly awesome. :)

Another fellow suggested that idea a few weeks back and I'm looking at a couple of designs we may prototype next month and see if we can get adequate stiffness.
 
Thanks Bill. I added you to the list and PM'd you.

Another batch is scheduled to run on the 27th and we'll do a bunch of those in gold.
 
The flanges got machined ahead of schedule and are at the anodizer now. Hope to have in hand by the 29th. We'll have gold, red and some clear to fill the existing orders.
 
I am a little bit concerned about the cut and re-weld operation. Perhaps some of you that have done that can reassure me.

On the engines with the rubber sleeve connection of the induction tube to the sump, I can see that alignment is not particularly critical, and welding the pieces back together by just 'indexing' the bandsaw cut should be fine. Any misalignment gets taken up by the rubber sleeve.

But for those of us with angle valve, horizontal induction sumps, where the induction tube fits into the sump with a big doughnut seal, the tube alignment is a lot more critical. It seems like if the rewelding isn't pretty much perfect, then tightening the clamp at the cylinder flange will put some bending moment into the assembly as it forces the tube flange to mate against the cylinder. Lots of possible consequences to this, perhaps the most benign being that the weld fatigues and cracks. Possible that the flange face, where the o-ring is, gets distorted by the clamping force and doesn't seal. Maybe even possible to put enough bending load into the cylinder itself to induce a crack at one of the studs?

So, short of welding in place, which seems pretty awkward on an installed engine, how does all this turn out?
 
Steve- having done a 200hp, AV, horizontal sump as the prototype for this product, IMHO, you would have to be really sloppy in your welding to mess this up. Yes, you could drive the condition which you fear, but reasonable precautions should keep it straight.
 
Just completed install

I just got done installing this on the IO-540 parallel valve in my Rocket and have some observations:

The kit fit perfectly once I got everything lined up. Looks great and I expect it will give very long service with no leaks.

The o-ring assembly is a real bugger until I learned to first get both of the flange bolts tightened up to where the flange was about 3/16" lower than the mating surface. Then I assembled the o-ring and aluminum washer and carefully slid the assembly into the 3/16" gap, pushing it around with the tip of a screwdriver until it looked like it was correctly placed. I then ran the nuts up snug by hand (no ratchet/wrench) carefully watching to make sure the o-ring wasn't pooching out and getting pinched somewhere - this happened to me twice. Once convinced I didn't have a pinched o-ring I then tightened the nuts with a wrench.

The new flange seems to be slightly thicker than the one it replaced, causing difficulty in tightening the back bolt on at least one of the cylinders. In general those back bolts are difficult to get to. A 7/16" socket that's somewhere between the length of a standard socket (too short) and a deep socket (too long) would probably help, especially if it had very thin walls.

A majority of my original (7-yr old) intake gaskets were in bad shape. One was in pieces - parts fell out when I was in the process of removing the bolts and hadn't yet tried to move the flange.

It takes quite a bit of ingenuity to get some of the supplied clamps in place. In general the one securing the flex tube to the sump is relatively easy, but the one holding the flex tube to the intake pipe can be quite difficult to get pliers on. I used a medium sized Channel Lock and on a couple of cylinders it took quite a bit of head-scratching to figure out how to get the jaws wide enough to grap the clamp with to first open it, yet close together enough to get the clamp expanded onto the flex hose. As might be expected the placement of the exhaust and intake pipes also doesn't help with access. A few creative helper words in the right spots and a couple of strategic time outs finally got me over the hump.

I haven't run the engine yet but it sure looks better than the old set up.
 
Steve- having done a 200hp, AV, horizontal sump as the prototype for this product, IMHO, you would have to be really sloppy in your welding to mess this up. Yes, you could drive the condition which you fear, but reasonable precautions should keep it straight.

What about the issue that the re-welded pipe is now shorter by roughly the bandsaw kerf width? Assuming you bandsaw cut it, then reassemble by putting the two pieces together, it is now shorter by, what, 0.050" or so.

Does that affect the sealing of the big doughnut seal where the pipe fits into the sump?

I'm guessing the sealing surface in the sump is long enough, (deep enough) that being a little bit shorter doesn't affect the seal? If it is just sealing in a cylindrical bore, that is probably true. If the seal relies on some compression from bottoming in the bore, then the shortened tube would not produce as much seal compression.
 
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Steve- the sump to tube seal is around the bore. The tube itself is free to translate in and out a bunch (probably +- a half inch). With amount the cylinders walk around in service this connection would never handle a rigid seal. The .050 change due to cut and welding is not significant.
 
A little guidance would be helpful. I just ordered my Lyc. IO390 from Van's. Should I consider using these as a preemptive measure?
 
A little guidance would be helpful. I just ordered my Lyc. IO390 from Van's. Should I consider using these as a preemptive measure?

These were created to solve a known problem that has plagued pilots and mechanics for decades. Bottom line: if your stock gaskets are not leaking yet, they will.

So yes, this is a good preventative measure.
 
Very effective

Installed a set along with valve covers. Been chasing what I believed was an intake leak, was getting some slight stumbling at lower RPM's

Was doing some other work work under the cowl as well.
When I started it up the first time I thought the Manifold Pressure gauge was broken. Was reading way lower then I had every seen it before.
After flying it, the gauge was fine. I just had that much of an intake system leak. Running way smother now at idle once it warms up.:)
 
Next batch

I picked up a another run from the anodizer this afternoon so will start contacting those on the list tomorrow as time permits.

Thanks for everyone's patience.
 
I've sent out many sets of these this week so far with some more to go out tomorrow.

The problem now is we're almost out of the clamps for the carbed engines which use a thicker wall hose. I already bought up all I could find from several sources and have been searching for more for the last 3 weeks to no avail. I have emails out to several manufacturers and distributors, hopefully something will come back soon.

Clamps for the injected engines are available but all I have is the green hose as I bought up all the black hose I could find weeks ago and now it's long gone. Hopefully I'll see my big order of black in about 2 weeks now. Been on order for 6 weeks.

I haven't forgot about anyone, it's just the list is very long and we only have time to ship 3 or 4 sets a day with our other work to do.
 
Vibrations - Gone

Installed Russ' o-ring intake kit last weekend. Took it out for a test flight, wow, my vibrations are gone. Manifold pressure at idle is around 10 inHg. Nice smooth running at low idle. Nice improvement to the plane. Thanks Russ.

Another satisfied customer.
 
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That's a pretty setup Alfio. Mike and Ross did it right. Their solution will be on my next engine :)
 
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