Patrick M

Guys - great discussion and insight on the SWTA (now ARI) cowl kit. I am sure it is one of these: https://www.aeroresourcesinc.com/proj98-ci/WebContent/product_category/view/9 I will call them to see what parts they have should I encounter the bulkhead crack again.

Interesting. Log books from 1984 indicate the Cowl was a Lasar 117 kit but that part number could not be found by Lasar.

I measured an M20J and found my cowl was 1" longer. Ideas appreciated.

My cowl looks like an M20J but is about an inch longer at the nose. It may have been part of a Lasar kit from the 1980s but I cannot verify. The 2295 kit is certainly for an M20J cowl.

The Hartzell A2295-5 Spinner Assembly and A2476-19 Mounting Kit (fasteners) is about $2200 at Lasar.

Tankertoad: My solution was to repair back to the original specifications. I found a good used bulkhead (680031-027) and repaired the cracked doublers (680031-029) as they are no longer available. Even the bulkheads are hard to find now. Only 20 hrs. ago so time will tell. The fatigue crack originating in the narrowest area is due to the stress of the vibration from the spinner. The doublers are so thin they provide little structure. I believe the key to minimizing this vibration is to carefully follow the shim-taping procedure (Hartzell Alert Service Bulletin HC-ASB-61-332) between the prop hub and front bulkhead which minimizes spinner wobble. In my application the tape was worn mostly off and hence the fit was loose. The tape is high-temp and specified in the bulletin. Another option is to upgrade. Dan at Lasar was very helpful and offered a new spinner/bulkhead conversion which works with the M20J cowl: Hartzell A2295-5P / A2476-19. It comes with the spinner, bulkhead, doublers and fasteners. It relocates the rear bulkhead from the flywheel/ring gear to the prop hub. The design is much better. Un-fortunately this kit would not fit my cowl which is 1” longer than the M20J.

Mike - agree on the root cause: wobble of the spinner due to gap between the forward bulkhead ring to prop hub dome. Shown on image: Red and Blue. Tape is used to make a snug fit. I have attached two related service bulletins. M201MKTurbo - good idea. I will give Laser a call. Clarence - carbon fiber or custom are an option I would consider if I can't find good used parts. Probably too expensive. I will study. Russell - original kit was installed in 1984. They were called Lasar Kits 100 and 117. No longer available. I saw a kit by ARI 680031-517:one recently sold on ebay which was also cracked. All - thanks for your ideas! M20-201 Bulkhead Spinner.pdf M20-219 Bulkhead Spinner.pdf

Alan - Hartzell HC-C2YK-1B / 7666-A2 Two blade with the "Q-Tip" spinner (see picture). 1967 Mooney M20F 200 HP IO-360-A1A with the M20J Cowl. I am also looking to upgrade to a non AD prop hub. Thanks! Scott - these are from a Hartzell assembly. I need to hold on to this one for now but if I find a replacement/upgrade then I could sell you the cracked one. Thanks!

Looking for spinner rear bulkhead part number 680031-027 or 680031-017 and doublers 680031-029 or 680031-025. I have had a stress crack failure a few times now on my M20F due to excessive wobble of the nose cone. This bulkhead and doublers enable conversion to the M20J cowl by adding the eyebrow cut-out. No surprise the stress crack starts from the bottom which is the weakest point (see pictures). These parts are becoming scarce. Thanks, Patrick