breeched oil gallery on new case

[SonexFactoryTech]

Yesterday Sonex Aircraft emailed the notice, below, to every customer we feel may have received a defective case.

At the time of this posting, only two defective cases have been identified (one still on our shelf). One of the customers who received our email yesterday confirmed that his case was NOT defective.

Note that the numbers cast into the engine case have no bearing on this issue. The error occurred in our supplier's machine shop where all of the machining was performed on the rough castings. All of the rough castings (for the entire VW Type-I aftermarket) come from a single foundry in Brazil.

While we do not wish to downplay the severity of the machining error, speculation and discussion is no substitute for performing the described inspections. If you find you have a defective case, contact Sonex Aircraft directly at tech@sonexaircraft.com and we will make arrangements to get you a replacement case and issue an RMA for the return of your defective case.

Below is the email we sent to each customer we feel may have been impacted by this issue:

_____

AeroVee Builders:

On May 2nd, 2016, we discovered that we delivered engine cases that may have a machining error from our supplier. We believe the extent of the problem goes back no further than our most recent delivery from our supplier. This email has been sent directly to the customers we feel may have been impacted and, out of an abundance of caution, a few customers who pre-date what we believe is the delivery date of the impacted cases.

The affected cases were delivered between mid-November 2015 and May 1st, 2016.

If you took delivery of a new AeroVee engine case between November 1st, 2015 and May 1st, 2016 – our records indicate you have which is why you’ve received this email - please perform one these mandatory inspections:

Unassembled engine:
Inspect the oil passage that feeds the center cam bearing for "break-out" between the base of the cylinders. This is shown in the attached photo by the appearance of the red straw. This break-out is the defect.

Assembled Engine:
If you have already run your engine and have proper oil pressure it is highly unlikely you received a case impacted by the machining error. The break-out of the oil passage would result in the loss of oil pressure. However, the only way to know for sure is to perform the inspection described below.

To inspect an assembled engine you will need to remove a cylinder head and one rear piston. With the cylinder removed you can inspect the affected area with a mirror.

If your engine is impacted by this machining error please contact us at tech@sonexaircraft.com and we will arrange to ship you a replacement case as quickly as possible.

Sonex Aircraft Tech Support

Sonex Aircraft LLC
511 Aviation Road
Oshkosh, WI 54902
Tech Line: (920) 230-TECH (8324)
Mon, Wed. and Fri. 10 AM to 12 AM and 2PM to 4PM CT

[n502pd]

Whatever Kerry is telling us is all I have. He should be the driver on this, and probably should be asked directly for other info? :?:

[n502pd]

Just an update on the breeched oil gallery problem. I got my replacement case Thursday, and inspected it this evening. All is right in Gunter Tx again. The new case is great on the inside and out. Nothing I can see that I will have to do except remove several shavings, clean it up and paint it up! Woo-Hoo! I am getting there!! :D :D

[paulonex]

I do not know the details of this issue ( is it a machined surface against a cast hole our a machined surface against a drilled / machined hole).
Either way a visual inspection is not any assurance that thing are good to go.
There could only be .oo1" of material and a visual inspection would look OK.
Sonex needs to understand the issue and come up with a way to assure a quality result (a "look" is only a first step given that there is a core underling issue).
They need to communicate the core problem and what they / their supplier is/has done to rectify the problem and what procedure they have put in place to assure compliance.
We are not building watches as John M. says, but we are building machines that are life could depends on the results

[n502pd]

I do not know the details of this issue ( is it a machined surface against a cast hole our a machined surface against a drilled / machined hole).
Either way a visual inspection is not any assurance that thing are good to go.
There could only be .oo1" of material and a visual inspection would look OK.
Sonex needs to understand the issue and come up with a way to assure a quality result (a "look" is only a first step given that there is a core underling issue).
They need to communicate the core problem and what they / their supplier is/has done to rectify the problem and what procedure they have put in place to assure compliance.
We are not building watches as John M. says, but we are building machines that are life could depends on the results

Very good question. Maybe you should ask for more clarification from Kerry, with your idea of , maybe, a thickness of material in that area that can be easily measured from the seating surface of the cylinder? Or maybe how deep that area is susposed to be machined from some other reference point? And then everyone who has an engine that might be affected would have hard numbers for a reference. There should also be go/no go limits too. If Sonex/Aeroconversions dosent know the level of concern in the field, then they can not respond to it properly, and completely. I am just saying...IMHO!! :)