[NSRCA-discussion] Looking For Props & Header

Thu Nov 5 08:24:25 AKST 2009

Matt:
Thanks--I'll give it a try.  But, I'll admit that I'd mix my fuel with snake oil if I thought it might help.  Frustration reigns supreme.  I should be practicing, and I'm trying to keep the engine from spitting off parts.  Sigh.
Bill
  ----- Original Message ----- 
  From: mjfrederick at cox.net 
  To: General pattern discussion 
  Sent: Thursday, November 05, 2009 11:52 AM
  Subject: Re: [NSRCA-discussion] Looking For Props & Header

  I ran an NMP header on a 140 DZ for a couple years with no issues whatsoever. As most people are aware, the 140 DZ had some of the toughest vibration to tame of any of the YS engines. Here's what I did (no, I did not use any Permatex): Install one extra copper gasket (I had heard the issue may have been with the threaded piece bottoming out in the engine head), and I also re-tightened the header as tight as I possibly could after getting the engine up to running temp (something to do with differential expansion of all the different metals used to mount the headers). I never once had the header come loose, even when the Genesis did a triple lindy into the base of a huge oak tree. The head wasn't atached to the engine anymore, but I'll be damned if that NMP header wasn't as tight as ever (twisted, but still tight).

  Matt

  On Thu, Nov 5, 2009 at 7:54 AM, Bill Glaze wrote:

   In my case, it's a fairly simple problem.  The  1.40L vibrates so much, that the stud unscrews from the head, leaving the header  dangling in space alongside the exhaust port.  I have about a foot of  Teflon tubing between the outlet of the header, and the inlet of the Hatori  pipe. I also have their (NMP) header brace in place to try to help  stabilize the header.  
  The engine has already, after about 6 flights,  broken a Johnson Header; that's why I am trying the NMP.  I got the last  NMP Central had in stock, and they said that the person who was making them is  not doing so any more. (That's what I was told, anyway.)   The  Hatori pipe is sitting on one mount, about halfway back on the pipe, and the  whole outfit is free to move back and forth along with the engine  movement.  I had hoped that, with the entire mess moving, it would permit  the stud to stay screwed in the head.  I'm worried lest the stud strip the  threads in the head.  The instructions say that "some people have had the  header loosen" and to try a certain type of Permatex form-a-gasket  material.  I've used this stuff before when I had a racing engine business,  but I certainly never used it in this type of application. 
  It seems to me that the entire problem is caused by  the excessive engine vibration that the 1.40L is known for. 
  Any help? 
  Bill Glaze 
  ----- Original Message ----- 
  From: Troy Newman
  To: General pattern discussion
  Sent: Wednesday, November 04, 2009 5:39    PM 
  Subject: Re: [NSRCA-discussion] Looking    For Props & Header 

  I    don’t know what you mean by will it stay attached? 

  The    new header is a wrap around style header like the previous NMP and the Hatori    822 style headers. 

  All    of the 120-170 engines have the same head configuration (meaning same angle)     and same thread size. SO the new header will fit all 120-170    engines. 

  There    is one exception. The 120AC has the air box on the back of the head. This    prevents the use of the wrap around style headers on this engine. Other than    that they are all the same. 

  The    NMP header was a really good header for the application. When we were using    Teflon tubing to connect the header to the pipe it was excellent. The problem    was Hatori went to the newer style pipes that the header slides inside of the    neck of the pipe with the o-ring. The aluminum tubing used on the NMP header    was not as bullet proof in this application. Remember the Teflon when hot    would flex. Now the header and the pipe are attached to each other. The header    slides inside the pipe and the result is there is still movement but the    stress on the thin wall aluminum piping is higher. Breaking, and the header    would get a grove worn in it. Actually the o-ring would pinch the aluminum    tubing to a smaller diameter and the header-pipe combo would leak. The added    stress of vibration and the direct connection many folks would break the    header tubing. 

  The    new header is similar to the Hatori in terms of connection to the pipe. So    that swedging ( shrinking of the dia at the o-ring)  problem and the    leaking should be solved. In my setup its working well on the proto-type    headers. Next issue is the tubing being stronger to take the stress of the    direct connection. The solution is kind of unique and is working well. Some    more testing and maybe a few tweaks and its going to be a very good    replacement for the Hatori 822 and 823. 

  Troy 

  From: nsrca-discussion-bounces at lists.nsrca.org    [mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Bill    Glaze 
  Sent: Wednesday, November 04, 2009 9:05 AM 
  To: General pattern discussion 
  Subject: Re: [NSRCA-discussion] Looking    For Props & Header 

  Troy: 
  Will the new header    stay attached to the 1.40 L? Bill Glaze 
  ----- Original      Message ----- 
  From: Troy Newman
  To: General pattern      discussion
  Sent: Wednesday,      November 04, 2009 12:35 AM 
  Subject: Re:      [NSRCA-discussion] Looking For Props &  Header 

  I      don’t believe there is such a prop made as the 18.1-11 Narrow. It doesn’t      exist. I may be wrong but I have been involved with running and testing the      APC props in the 18.1 series and WPN series.  There is a prop that is      designated as just 18-11 and this has a narrower blade than the      18.1-11.  The 18.1 series of props have a very wide blade. The 18-11 is      more like a 17-13 or 17-12 in terms of blade shape but its 18in dia and 11      pitch. 

  I      know there is a 16.5-12 I just pulled one out in my box-o-props and it has a      profile like a narrow prop very similar to the 17-10N
however it doesn’t      have the designation as 16.5-12 narrow. It’s just called the 16.5-12. If you      handed it to me with the name scratched off and said it was a 16.5-12 I      would have said it was a Narrow.  Same goes for the 18-11 regular it’s      a narrow essentially as well. 

  I      don’t know for sure why the “W” designation or the “N” for narrow is left      off of some props and added to others. I think it has a lot to do with the      equations and program that is used to create the prop profile. 

  To      sum up the props APC has the prop if it is or has been produced.  I      don’t think Fred throws any of the molds away. So if a prop was produced at      one time it might be possible with some convincing to get some of them      produced again. I have been to the factory where the props are produced. It      amazing how they are produced, and the quantity and quality of props      produced for a given size. 

  You      may not be asking for it by the proper name/designation
.the 16.5-12 (is      actually like a narrow) and the 18-11 is like a narrow version of the      18.1-11 

  As      for Headers
..the new header is in testing and is performing well. The jury      is still out, we are working hard to insure the bugs are worked out. Right      things are going well and real progress has been made in the last couple      months. It will be sooner rather than later from the looks of things on the      new headers. 

  I      hope this helps answer the questions 

  Troy      Newman 

  From: nsrca-discussion-bounces at lists.nsrca.org      [mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of rjo626 at aol.com 
  Sent: Tuesday, November 03, 2009 8:20      PM 
  To: nsrca-discussion at lists.nsrca.org 
  Subject: [NSRCA-discussion] Looking For Props &  Header 

            Hello all! I'm looking for APC 18.1x11 narrow, and 16.5x12 narrow.      Also, 
  anyone      have a good NMP pattern header they're willing to part with / sell? I've 
  tried      Central Hobbies and APC with no luck. Thanks a      bunch! 

            Later! 
                   RJO 
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