John Marzulli's Blog – January 2013 Archive (2)

Still Working On A Root Cause

We are still trying to figure why exactly all the coolant came out. The best hypothesis is an airlock developed in the system and forced the coolant out.

That still leaves us wondering why the airlock started in the first place.

Once piece of the puzzle has been figured out, which sadly creates a new question. The bottle failed due to exhaust heat. We were seeing EGTs close to the yellow\warning zone before the failure. The portion of the bottle that melted was…


Added by John Marzulli on January 10, 2013 at 3:17pm — 4 Comments

Engine News

Some good news:

First the cylinder bodies were all fine. They measured in spec and had no scaring and no signs of warping.

The better news is the cylinder and heads all passed their hardness tests. The minimum hardness of the heads is 85HB and the Cylinders 90HB.


The heads measured between 102-134 and the cylinders 108-118. The lowest values were for #1 head and #2 cylinder.

As expected the bolts were all loose from the…


Added by John Marzulli on January 9, 2013 at 3:01pm — 11 Comments

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.

Custom Upholstery Kits for your Zenith Aircraft:

Zenith Vinyl Upholstery Kits

Zenith Apparel from EAA:

Zenair Floats

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

Builder & Pilot Supplies:

How to videos from

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 for the latest DVD titles.

Aircraft Insurance:


West Coast USA:

Pro Builder Assistance:


Transition training:

Golden Eagle Aviation

Pianosa Flying Farm

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

© 2021   Created by Zenith.Aero.   Powered by

Badges  |  Report an Issue  |  Terms of Service