R

Ron B.

Well Known Member
Got a chance to see an ECI cylinder failure yesterday. The cylinder failed at the junction of the sleeve to head just at the end of the threads like all the failures in the AD. This cylinder serial number is, 19372-20 which puts it in the group A list. ECI was surprised to here about this failure and stated that this serial number belongs to a non defective part and should not have failed. They did offer a discount for replacement ,but no questions or wanting to see the broken parts leaving me to believe that they have experienced this before in the serial numbers similiar to this one. Now this is just my opinion and that is all it is "my opinion".
Anybody else have a culinder fail on a group A ECI cylinder?
Ron
 
I hadn't realized how rare blowing the head off a cylinder was til now. Searching on the net revealed a different picture!!
Ron
 
This might warrant a call to the FAA's aerospace engineer responsible for the AD to pick his brain about failures among other serial numbers which "should" be unaffected. The contact person is always listed in the AD.
 
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Read the article by Mike,can not recall his last name in the Feb 2013 issue of Sport Aviation, I think it will shed some light on these failures which actually are pretty rare.

Smilin' Jack
 
Cylinder failure-why?

A man I used to work with called cylinders the "garbage dump" of the engine, meaning anything wrong with the fuel system, intake system, ignition system or cooling system manifests itself as a problem with (or in ) the cylinder. Then the simple summary is, "Manufacturer X made a POS cylinder".
Most folks know that the steel barrel is threaded into the aluminum cylinder head and the assumption is that the threads are what secure the head to the barrel. Not true. There is a shrink fit of the head on to the barrel and that shrink fit is what holds the head on to the barrel. If the head is heated up to a point where the shrink fit diminishes and the load of combustion is transferred solely to the threads, it's gonna come apart. Usually right at the top thread of the barrel.
The head/barrel shrink fit is an engineered clearance imparted at manufacture and any operational condition that weakens that jeopardized the security of the head/barrel joint. ECI guy wrote a series of articles about that last year and they are on the ECI website. It highlights how bad baffling and glazed barrels can contribute to heads breaking. Above 460 degrees the security really falls off.
I can't believe ECI wouldn't want to look at the broken cylinder. Talk to either Tim or Ruth and I bet you'll get a different response.

Keep 'em cool, keep 'em flying.

Grub
 
grub0927 said:
The head/barrel shrink fit is an engineered clearance imparted at manufacture...
Click to expand...

The screwed-on cylinder head is a really silly idea and is really only relevant from a historical perspective, especially when today the bores are Nikasil-type plated anyway. I think the single-piece heads of the Franklin or Andrew from AC Aero's new cylinders are today's solution. I can't wait to see how well they turn out.
 
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