Throttle cable adjustment

[Skyland field]

Hello all,
Wrote recently about throttle cable snapping in flight. Thanks for all the comments received.
Went up yesterday with new cable installed by A & P at my airport. Worked smoothly but only got 2800 max rpm where it used to get 3300. Jabiru 3300A engine.
Looking at the Aero injector manual I would think the adjustment is just in the hand throttle lever and not down on the engine side.
Would loosening the nut and having lever at full throttle position be the correct way to adjust this. At that point pull cable rearward until it stops and that would be full throttle, then tighten.

Any suggestions once again would be appreciated.
Ed

[gammaxy]

When I installed my throttle quadrant, I pulled the throttle cable to full open (verified by looking through the throat of the Aeroinjector). I then positioned the throttle lever most of the way open, with an ~1/8" gap before the forward limit. This way, I know that it's not the throttle quadrant limiting wide open throttle.

Before you adjust anything, visually verify whether the throttle lever is hitting a stop at the full throttle position.

If you don't already, it's a good idea to know your static rpm so when an adjustment like this is made you can do a full-power run-up to verify and not be surprised by a lack of power in flight.

[Skyland field]

Thank you Chris,
I'll be heading back out Wednesday to see about adjusting it. Will take your recommendations.
Ed

[mike.smith]

Like Chris I verified the movement of the slide, and set my cable adjustment from that.

Also, while flying WOT did you check if you got a rise in RPM by making the mixture a little leaner? At one point I found I was running too rich and 'drowning' (my words) the engine in gas. My first clue was when the engine would stumble at a full-rich take-off. I had to pull the mixture out 1/2" to get it to run right.

And during flight pushing the mixture in 1/4" to 1/2" likewise made it run much better (RPM, smoothness and fuel burn). So I adjusted the mixture cable at the AeroInjector arm. I would say don't just go by the "45 degree angle" quoted in the manual. I did it with a protractor but found that the mixture was still not where it should be. Now it runs great at all times.

[Skyland field]

Good tip. Seems to run fine at the 2800 but will check that in flight before I try the adjustment.

[kmacht]

May not be the problem but try throttling back about a 1/4 inch. I get higher rpms and smoother running on my aerovee/aerocarb with the throttle back just a little from full open. Don't know why but there used to be a number of threads discussing it on the old Yahoo groups site and it is mentioned in the aerocarb install manual

Keith
#554