AeroConversions discovered today (Friday 8.19.11) that incorrect hardware had been labeled as ACV-Z01-36 Flat Head Cap Screws and shipped to customers. P/N ACV-Z01-36 is a 1/4-28 thread x .75" long Flat Head Socket Cap Screw (Fine Thread). This Part Replacement Notice impacts AeroVee Engines shipped between March 2010 and today (Friday August 19, 2011).

The entire stock labeled on our shelves were actually 1/4-20 thread x.75" long Flat Head Socket Cap Screws (Coarse Thread).

These screws secure the secondary ignition trigger shaft assembly to the flywheel and are installed by the builder, not pre-assembled by AeroConversions.

The ACV-F01-11 steel center fitting in to which these screws thread is drilled and tapped for a 1/4-28. A coarse thread socket cap screw can be installed and will give the incorrect impression that it's provided a tight fit. The resulting joint using this hardware is not acceptable and must be repaired.

All AeroVee Customers who received their engines since March 2010 and have not assembled their engines must immediately check your ACV-Z01-36 Screws and verify they are the correct 1/4-28 thread. If found to be the incorrect thread, please contact us immediately at techsupport@aeroconversions.com and we will send you the correct hardware at no charge.

If the ACV-Z01-36 hardware has already been installed, the alternator cover plate should be removed and one of these 4 screws should be removed and verified for proper thread. If they are found to be coarse thread, then a re-tapping to 1/4-28 can be attempted. If this does not succeed, the flywheel should be removed and the 4 mount holes should be up-drilled and tapped for a 5/16-24 x 3/4" length thread flush head cap screw. Please refer to your AeroVee Assembly Manual for the proper installation instructions for this hardware.

Accessory Case/Flywheel Centering Check:
We have found that a few of the Supplied Crank Cases (Old P/N 1274 New P/N ACV-P01-36) do not have the transmission locating/centering boss on the flywheel end of the case concentric with the crankshaft bore. This does not impact the operation or service of any of the AeroVee Parts. It can, however cause a slight mis-alignment between the AeroVee Accessory Case (x-mount P/N ACV-A01-01) and the center of the crankshaft. If this misalignment is more than 0.015 inches, the alternator stator can contact the magnet ring, causing, in extreme cases, the stator to be burned up.

The identification of this problem and the fix are both simple procedures: The following check is required BEFORE RUNNING YOUR ENGINE FOR THE FIRST TIME:
Step 1: Remove the Alternator Mount Plate and " Paint " the outer surface of each coil of the alternator stator (See Figure 1 and Figure 2) and inside of the magnet ring Blue (See Figure 3 and Figure 4) with a permanent blue Sharpie Marker.
Step 2: Reattach the stator mount plate assembly to the Accessory Case. (Reinsert as carefully as you can to keep the Blue Marker intact. Also remember that the magnets are strong! They will pull the alternator right out of your hand and can pinch your fingers).
Step 3: Remove one set of spark plugs and manually rotate the crankshaft (turn the engine over) 3 or 4 revolutions. A socket on the prop hub attach bolt works well to pull the engine through.
Step 4: Remove the stator mount plate assembly and inspect the blue paint on the stator and magnet ring. (Again use care to keep from scratching off the Blue Marker as you remove the stator). If the blue marker is intact on both the stator and magnet ring, your alignment is acceptable. If either the stator or magnet ring show signs of contact, proceed to Step 5.
Step 5: Remove material from the Alternator Stator using a belt sander or equivalent where the Blue Sharpie has been wiped from the Stator. (See Figure 5 and Figure 6) Repeat Steps 1 through 4 until no contact is evident. Note that this same procedure can be used on the primary ignition (magnetron units) by " painting " the trigger magnet on the flywheel to ensure no contact is occurring between the magnet and ignition module.
(list of all images for this Service Notice):
Painting the Stator- Figure 1
Painting the Stator- Figure 2
Painting the Magnet Ring- Figure 3
Painting the Magnet Ring- Figure 4
Removing Material from the Stator- Figure 5
Removing Material from the Stator- Figure 6

Proper Grounding Procedure:
The red anodized surfaces of your AeroVee Engine Components act as an insulator. For the primary and secondary ignition coils to function properly, they must be grounded. In order to ensure their proper function, we highly recommend the installation of a ground wire to the body of each ignition unit. This ground should be routed directly to the engine crank case. Below are images of the areas to place a ground wire for the Primary and Secondary Ignitions (see images below):
AeroVee Primary Ignition Grounding
AeroVee Secondary Ignition Grounding

New Assembly Procedure for Flywheel:
The o-ring mounted in the steel center fitting of the flywheel has proven to be a challenge to install for some builders and has the potential to cause a problem by getting pinched in between the flywheel and back of the crankshaft. This can keep it from seating all the way and can cause the flywheel to turn off-center leading to potential ignition and alternator problems. We recommend removing the o-ring and applying a light coat of high-temp silicone sealant to the dowel pin area and a 1/8² diameter bead in the o-ring groove.(see image below):
Flywheel High-Temp Silicone Application

General Prop Hub Assembly/Removal Practice:
Do not use a propane torch or other flame to remove shrink-fit components under any circumstances. If you have used a torch on any of your shrink-fit components, they MUST be replaced immediately. The proper removal procedure for all of your shrink-fit components is to use a hydraulic press with no heat applied.

One other quick note on ongoing maintenance and supplemental materials for your AeroVee. There are some excellent reference materials available that we strongly urge all AeroVee builders to purchase, read, and add to your permanent reference library as supplements to the AeroVee Assembly Manual and DVD. These materials are available at most major bookstores and online from the major book sellers.

One book in particular has become the vw builder guru's primary reference book. This book is titled " How to Rebuild your Volkswagen Air-Cooled Engine " by Tom Wilson (1987). Any AeroVee Builder who reads this book cover-to-cover will be prepared for most any maintenance issue and will have a better working knowledge of the VW Engine from the inside out.

Optional Dual Ignition Upgrade:
The AeroVee now comes standard with a Secondary 12V Ignition System. This was incorporated to meet Foreign (European) Market Requirements, to meet the ³Light, Sport² Aircraft Manufacturing Engine Standard, and aid starting in all conditions. This Secondary Ignition is clean and simple. It operates with one moving part (no additional drive gears), is mounted on the back of the engine keeping smooth cowl lines, and adds only 2 lbs to the engine package. The new price for the AeroVee system is $5695.00 and includes the Secondary Ignition System.

Previous purchasers of the AeroVee engine may elect to upgrade their AeroVee to include the new Secondary Ignition System. The total cost to you will be USD$500. This includes the machining for Dual Heads and all the components you¹ll need to fit the system to your AeroVee. Note that this can be easily retrofitted to your AeroVee without removing the engine from the airframe. If you¹d like to get this upgrade, remove and return you cylinder heads (P/N 1446) and your Alternator Stator Plate (P/N ACV-A01-12) and these will be returned to you modified for the dual ignition system along with the rest of the component parts and hardware. (Shipping Address: Sonex,ltd, 511 Aviation Road, Oshkosh, WI 54902)