Al Gietzen wrote:

I'm using the stock primary fuel rail and injectors on my 20B,

and a TWM

throttle body with it's secondary fuel rail.  The stock primary

rail has

a

pulse dampener at one end where I intend to weld on a -6 fitting

for a

series connection from the secondary rail.  It seems easiest to

just cut

it

off and put on the fitting.  Is there a good reason to keep the

dampener

on

there?

Thanks.
Al Gietzen

Al, I have a friend in CA who has his own shop repairing Mazda

Rotary

engines for over 20 years.  He says to ditch the fuel rail pulse

dampener as

it is only a matter of time (not if) before the pulser develops a

fuel leak

due to fatiguing of the dampener disk.  FWIW

Ed Anderson

Snip

       Paul and All,
           I believe we have a major safty problem here. We need to put

an "AD" out

 to all that plan on flying the 13B or 20B using the stock primary fuel

rail that

 they should remove the pulse dampener.
           Just a week ago a friend asked me to look at a fuel leak on a

87 RX-7. It

 was leaking profusely when the fuel pump was activated. To make a long

story short

 it was the pulse dampener. Since I do not work on RX-7's for a living I

thought it

 was an isolated incident. Ed's post brought to light that we who want

to fly these

 things have a inflight fire fed by 40 psi of fuel just waiting to

happen!

          Kelly Troyer

It is true that the pulse dampener is a well known failure point (fuel leak)
in the Mazda rotary.  Still, Mazda put it there for a reason so I'm still
using mine.  The purpose is to dampen out fuel pressure variations caused by
two sources:  1. fuel pump pulsations and 2.  injectors switching on & off.
Those of you who remove the dampeners could help us all by reporting on any
anomolies you may notice.  The ones I would expect are EGT variations
between the two rotors.  The variation would likely change depending on
engine rpm.  If you get any unexplained EGT imbalances, let us all know.
EGTs should match within 50 degrees or less.

Tracy Crook
tcrook@rotaryaviation.com
www.rotaryaviation.com

 
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