John,
You can send your injectors to have them flow tested and cleaned for
about $17 each plus about $5 each way for shipping the entire batch. That
will be about $80.
http://www.cruzinperformance.com/fuelinj.html
Rich at cruzin performance did mine.
You can check to see if they are leaking by pulling them out of the
engine with them still attached to the rail. (use a wire to firmly attach them
to the rail so they will not blow out) turn on the fuel pump. If
there is a leak they will drip.
I doubt the problem is with the injectors leaking because the engine
runs poorly when on the injectors, but not on the carb. When air flows
thru the carb, fuel in the carb will be sucked into the intake. That could
cause the engine to run rough on the injectors and if the supply continues, the
engine would keep running when the injectors are shut off.
But the first thing you are going to have to do is isolate the problem
to either of the two systems and then fix the bad one. As long as you
keep running both systems, you are going to have difficulty determining what
the problem is. Disable one or the other so there is no way it can get fuel or
introduce air and check for how it runs, then do the other one the same
way. At least you will know which system is screwed.
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of John
Sent: Friday, September 18, 2009
9:38 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Mixture
Condition
Gentlemen, thankyou for your input. I talked with Bob
White tonight and he thought that the #1 primary injector may be sticking open
and letting the fuel run and keeping the engine running. Try doing that
on a recip engine and see how long the muffler lasts. Not sure how to
check for this condition, as when it finally stops, I turn on the LP
pumps and start the engine so the pressure on fuel injection doesn't bled to
zero, putting the fuel into the standing engine, then I let the fuel burn out
of the carb until it quits. In a few minutes it will start and run normal
again and will stop when you turn off the injectors and as it gets hot again it
repeats the cycle.
Does anyone know of a reasonable substitute for Mazda
injectors, their price is quit steep.
I can plug the fuel line to carb, but I don't believe
that after 7 hours of running that gas would start siphoning up to the carb and
with the fuel pump and injectors off it keeps running until the fuel pressure
gets down to 17#'s before it quits. The fuel pressure is holding a steady
41 pounds when the engine is running normally. JohnD
Sent: Friday, September
18, 2009 4:57 PM
Subject: [FlyRotary] Re:
Mixture Condition
With such an odd
assortment of symptoms I suspect that you may have more than one problem.
This is the hardest situation to diagnose because fixing any one thing will not
make it right, only change the symptoms.
If there IS a single problem, it is to be found by finding what makes the
engine run with all injectors disabled. This can't happen unless
there is a major problem somewhere. I would suggest fixing this
first.
Tracy Crook
On Fri, Sep 18, 2009 at 1:08 PM, John <downing.j@sbcglobal.net> wrote:
I have narrowed the mixture condition down to the fact that
when it starts to miss up I can keep it running poorly by turning the mixture
control down to minimum, but if I turn off the primary injectors switch the
engine appears to run okay, the secondary injector switch doesn't
seem to make any difference in the way it runs at 4000 rpm or idle. The
injector switches as well as the wiring harness I purchased from Bob and all
wires are soldered and covered with heat shrink. I checked the best I can
with a light and mirror and everything looks okey under the panel. It
runs the same, rather in mode A or B. On rereading the instructions I see
that the coil disable can only be checked in mode B, so I haven't done that
yet.
I turned of the fuel pump and with the injector switch's off
the engine continued to run until the fuel press was down to 17 pds. and
quit. I turned on the fuel pump (LP) to the Weber and it started
immediatly. This condition started at 7.2 on the hour meter. I
really now don't have any idea where to start looking for the problem.
JohnD