Jabiru CHT temps high one one side - EGT's OK.

Jabiru CHT temps high, on 2,4,6, but 1,3,5 OK.

All EGT OK.

I flew my new Zodiac for the first time today, It was great, except for the high CHT.

I had someone else fly it first, did my GA conversion and flew it today.  I was told cyl 4 was too hot (170 C), so I installed a baffle in the ram air duct above cyl 4. (Jabiru 3300), The test are much cooler.

When I flew it cyl 6 was hottest.= the baffle cut air to 6.

I tried cutting off the lip on the cowl, and moving it back, made it slightly better, but still too hot.

It is running a bit rich, but I will leave that until run in,

I am thinking of cutting the exhaust pipe which extends about 8" past the cowl to a close fit, I am told that may help.

My next steps are to experiment with the cowl shape.

Any constructive ideas welcomed.  Can;t wait to sort this so I get to the real flying.

 

Bob Emery

Newcastle NSW Australia

 

Views: 548

Comment

You need to be a member of Zenith Aircraft Builders and Flyers to add comments!

Join Zenith Aircraft Builders and Flyers

Comment by Robert Emery on June 26, 2011 at 1:53am

Thanks for the replies.  I installed an aitr intake divider today.  Amazed at the results.

I now have much improved CHT;s when I flew today.

I also am experimenting with the lower cowling lip - position, size and angle.

Great stuff.

Bob Emery

Comment by Michael Herder on June 25, 2011 at 9:33am
As you've may have heard before, an intake divider helps tremendously.  my EGT's and CHT's are all tolerable with about 10 or so hours of tinkering.
Comment by Michael Herder on June 25, 2011 at 9:32am

Try tilting your bing carb. It makes gets more fuel to your lean bank of cylinders and helps them run cooler.  It really makes a difference.  When you tilt, double check to make sure you have full control of the throttle through all ranges.  Ask me how I know:).

 

Are you monitoring your EGT's?  The advice I just gave assumes that some of your cylinders are running lean, and therefore hot.

New from Zenith:

Zenith Planes For Sale 
  

Classified listing for buying or selling your Zenith building or flying related stuff...

Custom Instrument Panels
for your Zenith:

Custom instrument panels are now available directly from Zenith Aircraft Company exclusively for Zenith builders and owners. Pre-cut panel, Dynon and Garmin avionics, and more.

Zenith Homecoming Tee:

Zenair Floats

Flying On Your Own Wings:
 A Complete Guide to Understanding Light Airplane Design, by Chris Heintz

Builder & Pilot Supplies:

Aircraft Insurance:

 
 

West Coast USA:

 
Pro Builder Assistance:

 

Transition training:

Lavion Aero

K&S Aviation Services

Aircraft Spruce & Specialty for all your building and pilot supplies!

How to videos from HomebuiltHELP.com

Developed specifically for Zenith builders (by a builder) these videos on DVD are a great help in building your own kit plane by providing practical hands-on construction information. Visit HomebuiltHelp.com for the latest DVD titles.

© 2024   Created by Zenith.Aero.   Powered by

Badges  |  Report an Issue  |  Terms of Service