crackheadmel

what about 18g wire? for both inner and outer? explaine please

Lynn E. Hanover

I decided that since I was cutting out a section of the inner "O" ring when building a "J" bridgeport, that the sealing was not that critical because there is only the contact between the rotor housing outboard of the now missing "O" ring and the cast iron. Only a layer of 100% GE silicone tub and tile caulk helps do the sealing.



I came across a supply of aircraft wire with a Teflon insulator and silver tinned stranded copper wire. Very nice wire.



I gave that a try in a 12A engine and used just the wire and a very small bead of silicone in the groove before pressing in the wire. I reused the black outer "O" ring by removing a small piece of the ring by cutting it through with a razor at a steep angle, and placing the joint at the top of the engine, so any leak

would then be visible. With a spot of silicone at the joint, I never had a leak. It ran a whole season. I redid the engine and ran the very same piece of wire another year. A friend of mine did the same thing but with regular Beldon 18 gage hookup wire (maybe Chinese)



He had no problems.



I had never had a problem with the stock seal, but sometimes I didn't have one when I needed to build an engine.



This is not some hop up trick. It just happens to work. If available, I would use the stock "O" ring seals.



This applies to NA 12As and early 13Bs. Inner seal only.





Lynn E. Hanover



Picture is the Mistral aircraft engine based on the Mazda.

The Ultimate 7

18Gauge wire? Now I've seen everything.

AnthonyNYC

I sent an email over to RA regarding the O Rings, here is the first response:



"What I CAN say is that I've personally sold over 1000 sets of the telfon rings in the past 5 years - those are just the sales that went out to private builders and do not include the engines that were over hauled by our partner builders. Of those sales, the only complaint I have ever received about the telfon O rings was once when we had a manufacturing error and the rings were too small. Of course we replaced all those rings (5 to be exact) at no charge to the customer. We not only DRIVE these O rings, but we also fly them in our personal plane, and they are also in use in several of our friend's planes. In retrospect, the fact that we can sell any product with so FEW complaints is rather remarkable in itself.



As you know, most the parts that we (or any other parts supplier) sell end up being installed by builders with varying skill sets and experience. The number of variables involved in any single engine overhaul is high. Once the engine is back together, and even if the job is of the highest quality, we then have to deal with how the engine is treated after it is back in service. We have to consider whether any modifications were made to the engine .. whether it was raced.. overheated for any reason.. boosted with nitrous.. the possible variables go on and on and on. In spite of ALL those factors, we run an average of .001% problem rate. I really believe that if there was a consistent manufacturing or design problem with the teflon O rings, we would have received a LOT more complaints and perhaps most significant, we would have experienced problems with our own engines or with those of our close friends. So far, we have not had that happen.



I also want to say that we encourage ANY CUSTOMER WHO HAS A PROBLEM to contact Tracy or I. If there is an issue with any of our products we like to know about it. We stand behind our products and if there is information that a customer is willing to share which will improve the reliability of anything we sell, or if we need to replace a defective item for a customer, we need to hear from the customer.



I will get back to you again after a tech review of the email."

AnthonyNYC

2nd response:



HI again Anthony - I talked with 4 commercial builders who use our teflon o rings.



I do not want to say anything to offend any builders, (and again, we are NOT saying that product issue can't happen) but the overall consensus is that the cause for "sudden over heating", etc is improper installation of the seals. When properly installed the round seal compresses perfectly into the "square" shaped groove. It IS correct that the seals do NOT install as easily as the stock seals - that is a fact. However, builders who use the seals believe the extra time is worth the increased longevity of the seals (which are usually reusable even after multple engine opens) . We have specific instructions we are going to start adding when we ship the O rings due to the feedback that you forwarded to me. Again, we appreciate the feedback, we are going to add the instructions and hopefully help future builder's to avoid disappointing results with the O rings.

rotaryinspired

What did you expect them to say. Yeah theres a problem?



I am glad to hear they use them.



Unfortunately I don't feel the same way after building 7 engines w/ them and pulling one apart. I can guarantee the oring wasn't pinched. I personally don't feel they fit the groove as well when torqued down.



Think about something, when you were a kid did any round toy fit into a square one? Why should I start trying it now.

Maxt

LOL....

In my opinion, they use the customer as their R&D department..

Just to add to the square groove, round ring subject, I tried these same style of oring in another application. I was rebuilding solenoid valves with round profile o-rings at work since the square oem rings were 4 weeks delivery, when I got the real rings and did the re-rebuild, I found the round profile ring had been extruded from the square ring land and made into a teflon wafer , they were just starting to leak, the lowest pressure area was to the outside of the valve and the material was being exposed oustide the valve body... Being that the land was round, as was the ring, fitment of the ring to the land wasnt any kind of problem. That application was liquid at 34 F and 60 psi..It might be more than the profile, could be the ring to groove size relationship as well.

BDC

Why can't they just be honest about it? They're basically using their customer base as their QC (quality-control) department. Basically, what they're saying is, they've never had any complaints. Well, I'm someone who's complaining who was also a fairly consiistently buying customer. Does my complaint not matter? Am I all the sudden thrown into the categories of not being a "commercial" builder or that I'm automatically "installing them wrong"? Good Lord! It's a ring that fits in the same-sized groove! How the hell can anyone screw that up!?



B

BDC

That's my opinion as well, Max. It seems that's what they're doing, similar to what I felt they were doing with their apex seals when they initially flooded the market with them in late '03 prior to several people coming back with scattered results of abnormal rotor housing and apex seal groove wear.



I still don't get it. Why ammend the installation document with notes regarding their difficulty of installation if there isn't a problem with their o-ring in the first place? (Remember the 0.001% figure) When the o-ring diameter is correct, the o-ring goes right in and is a piece of cake to install. Why make a comment then about their difficulty? Maybe I'm just splitting hairs here but I still feel as if their response to Anthony wasn't an honest one. Does my complaint all the sudden not count? Am I not a "commercial" builder (what the heck qualifies for that anyways?) And, why are they not acknowledging my data regarding random overheating symptoms of motors that have never exhibited such symptoms prior nor ever enountered any conditions that would contribute to overheating?



I know all about the stigma associated with warrantying motors. I get asked alot on whether or not I do. I know full well being not only a builder but also an active enthusiast what can happen with a motor when the hardware isn't setup right or is abused or neglected in ways that can contribute to failure. I'm not an idiot. I know what things can happen having caused them myself in the past. With this, and while I'm not a perfect person, it seems to me that it would behoove them to take what I have to say seriously when I assert that I've got motors that I've built with their o-rings that are experiencing problems that I may have to potentially fit the bill for (arguably) due to the use of those same o-rings.



Goodness gracious. It's this kind of stuff that really hacks me off and is also one of the reasons why I am no longer a customer.



B

j9fd3s

not to single RA out, but it seems like there have been so many shops that come out with some product or service, and then they overnight, get this "they are the best" reputation.



and then you wait a few weeks or months and the stuff that was some miracle save all, is now trash.



if you need an example, how about pineapple? or the "anti detonation kit"