SonexBuilders.net

Look at this: ACV-SB-061714

Sonex Aircraft requires the immediate replacement of all ACV-Z01-36 (3/4” long) Flat Head Socket Cap Screws that hold the Trigger Shaft Assembly (ACV-F01-24) to the Flywheel with ACV-Z01-81 (7/8” long) Flat Head Socket Cap Screws. The ACV-Z01-81 screws provide added thread engagement to help prevent these screws from potentially backing out. Applying Locktite Primer and 242 Threadlocker, and using the proper tightening procedure on these cap screws are also extremely important.

See the following AeroVee Installation Manual Page that references this hardware and details the proper assembly, Download: ACV-SB-061714_Flywheel_Cap_Screws.pdf

All AeroVee Engines sold since late 2012 include the longer ACV-Z01-81 Cap Screws.

Any AeroVee Engines sold before late 2012 that have the ACV-Z01-36 (3/4” long) Flat Head Socket Cap Screws on the packing list and/or installed can obtain new ACV-Z01-81 (7/8” long) Cap Screws at no charge. Please contact the Sonex Aircraft orders department to initiate this order, reference ACV-SB-061714 and include part numbers ACV-Z01-81, Qty 4: orders@sonexaircraft.com

Charlie,
Thanks for posting this, I've got my order in. For whatever reason, I didn't get the SB email from Sonex-- I'll have to be sure I gave them my current email address.

I got my order in as well but this would have been alot easier to accomplish last year when I already had the engine off to replace the stator screws.

Keith
#554

I will probably wait until my next annual to apply the SB. (You watch...I'll be the one that it happens to next).

It kind of funny. Both times a service bulletin came out on the alternator, my engine was already apart for some reason. Lucky me, Ha Ha!

It will not get above 2700 rpm static at 1000' elevation. It has only 10 hours on the engine, runs fine and
out side of requiring 1300 ' to get off the ground, it flyspeck fine. The plane is a Onex. I know it will develop more rpm as it breaks in but is this normal at this point.? I get 2900 in level flight at 140.

Gtragesser wrote:It will not get above 2700 rpm static at 1000' elevation. It has only 10 hours on the engine, runs fine and
out side of requiring 1300 ' to get off the ground, it flyspeck fine. The plane is a Onex. I know it will develop more rpm as it breaks in but is this normal at this point.? I get 2900 in level flight at 140.

No, this is not normal. Something is definitely wrong. You should get at least 3000 rpm static.

Mine won't go 140 at 2900------Your Tack or Airspeed is off
Merle reppert

Or propeller. Based on low static RPM, somewhat extended T/O run, and 140 @ 2900RPM you may have a prop with a bit more pitch than others. Can you maintain a higher RPM (than 2900) in level flight?

Just as an FYI, I received my new ACV-Z01-81 screws in the mail today from Sonex.

From start to finish, this SB took a little under an hour to complete.

I had no luck finding Loctite Primer at any local stores so I completed this without it; I was told that the only real purpose of the Primer is to accelerate the cure time of the actual sealant. Has anyone heard this? I'm not opposed to performing this job again if the Primer is actually needed, but most feedback thus far says that, as long as you let things cure a full 24 hours, it's not really needed. Regardless, I plan on letting the sealant cure for a few days then check the screws after a few hours of flight time.