SDS No More Leak Induction Tube Solution

rv6ejguy · #1 06-01-2018, 04:26 PM

We've been working on this design from a concept submitted by Michael Robinson (Toobuilder) for some time now. With machine shop time being constantly tasked to supply normal parts for our EFI kits, it seemed to take forever to get these prototyped, tweaked and tested. We finally have production parts available.

These use a COTS silicone O-ring to seal the tube flange against the head, eliminating the flat gaskets which have been known to leak and cause grief on occasion.

Like our SDS valve covers, these billet flanges tighten down flat with even, metal to metal contact so there is no more flange distortion or "give" in the gasket over time.

They will come as a kit which also includes the O-rings, silicone hoses and constant tension clamps to replace the factory parts. For carbed engines, we'll supply new standard rubber hoses and Viton O-rings. Will be available for both 1.5 and 1.75 OD induction tubes, in gold or red anodized finish.

I'll try to get a photo of the complete kit this weekend.

Mike S · #2 06-01-2018, 04:52 PM

Oh my, and I am now stuck in the certified world

rv6ejguy · #3 06-01-2018, 05:56 PM

Quote:

Originally Posted by Mike S

Oh my, and I am now stuck in the certified world

OK. What have you done with the real Mike Starkey?

Toobuilder · #4 06-01-2018, 09:58 PM

After trying several different gaskets including paper, composition, silicone and even dead soft copper, I threw a rough O ring idea at Ross and sure enough, he took it and improved it. Some prototype parts showed up in my mailbox and I promptly installed them on the -8. Keep in mind the -8 is an angle valve, requiring the added step of cutting and re welding the tubes to replace the flange clamps. Easy, but not required on the parallel valve engines.

Anyway, once the new clamps are on the tube, you simply install the O ring over the inner retainer and slip the assembly in place between the head and clamp. Snug up the bolts to spec and you are done. Unlike with the paper gaskets, it is impossible to bow the retainer or over compress the O ring. It's simply a install and forget thing.

There have been many attempts to "fix" the induction leaks at the head over the decades since the Lycoming was designed - this is finally the one that works.

rv6ejguy · #5 06-02-2018, 03:37 PM

Here's what the whole kit looks like for a 4 cyl. (will have 8 clamps of course)

For injected engines, the price is $60US per cylinder.

Carbed engines are a bit more as we have to supply a standard hose which is more expensive than the silicone ones.

Thanks to Mike again for his good idea and for offering to test these for us.

vic syracuse · #6 06-02-2018, 05:31 PM

That is really neat!!!

Vic

flynwest · #7 06-03-2018, 07:22 AM

Sign me up for a gold set. Angle valve engine.

BillL · #8 06-03-2018, 09:39 AM

The latest parallel valve engines (M1B) is made like your angle valve description and would need the tube cut/welded. Then, it has a formed flange for a fat o-ring fitting into the intake manifold/oil pan.

Kudos!! So let me understand, the intake tube flange will sit hard on the new flange on the bottom, then the o-ring seals between the top of that flange and the head, with the addition loose ring providing a hard clamping on the top side between the flange and head? This will result in the top end hard clamped with the ring insert, sealed with the o-ring, and floating (head motion) on the intake end of the tube?

In rewelding the tubes, do they need to be tacked in situ to ensure they are aligned and flat against the head?

FasGlas · #9 06-03-2018, 12:42 PM

Perhaps you should offer a flange only kit for people with cold induction. They won't need the sleeves & clamps.

snopercod · #10 06-03-2018, 01:15 PM

This is a great idea, but I'm not visualizing how it would all fit together on my carbureted O-290-D2. My intake tubes have flanges on the ends. So the new billet pieces (not sure what you call them) would slide onto the tubes and the flange on the end of the intake tube would seat metal-to-metal into the billet piece? Is that right? Then the O-ring would be inserted on top of the intake tube flange, and that shiny metal ring (not sure what you call that, either) would also fit on the intake flange inside the O-ring? Is the purpose of the metal ring to keep the O-ring spread? Also, I don't understand why would I need new hoses and hose clamps?