Are there many folks out there who have had cracking problems on the McCauley spinner bulkhead pt # D7524 ??
I operate D2A37C230/90REB-2 McCauley prop on my C-180 with that new type pointed spinner. I have had this backing plate bulkhead crack twice in the past, and now a friend of mine has just found his second one crack.
What is up with this? It seems like this bulkhead design is inadequate.
Feedback welcome ...

Although relatively unlikely with a 180 or any other tail dragger, the single most common reason for cracked spinner plates is pushing on the spinner--not unusual with trikes. As "solid" as they may look, they aren't solid at all. If the prop has to be used to push at all, the hands need to be near the spinner, but never on the spinner. I've sure seen a lot of "helping hands" push on spinners, but that's always been on trikes.

The only thing that comes to mind why a spinner plate on a tail dragger would crack is an unbalanced prop, but I would think for it to be that bad, you'd be more concerned about serious vibrations.

Cary

54c180 wrote:Are there many folks out there who have had cracking problems on the McCauley spinner bulkhead pt # D7524 ??
I operate D2A37C230/90REB-2 McCauley prop on my C-180 with that new type pointed spinner. I have had this backing plate bulkhead crack twice in the past, and now a friend of mine has just found his second one crack.
What is up with this? It seems like this bulkhead design is inadequate.
Feedback welcome ...

Seems to be pretty common, I think I have read about 3 and have had 2 myself in the last 2 years.

Nope never had this problem. On my second spinner and first backing plate.

I have had this as well. I understand that the supporting packing at the front is important and the preload is half of the screw hole (if that makes sense)

From McCauley:Our spinners are lightweight and designed with a unique front support that automatically centers the spinner during assembly. The support itself is made of a synthetic material pre-loaded during installation that helps dampen vibration

Hamish

The airplane I fly is on its fourth bulkhead. No real reason found. I set the spinner preload correctly using factory shims but when I take the spinner off, the centering support has little plastic hairs coming off of it like it has been rotating. I'm stumped.

joshuajayg wrote:The airplane I fly is on its fourth bulkhead. No real reason found. I set the spinner preload correctly using factory shims but when I take the spinner off, the centering support has little plastic hairs coming off of it like it has been rotating. I'm stumped.

Yikes ...
Where do you buy the bulkheads and how much$$
Poor design, inadequate
There needs to be an upgrade on this installation ...
Have you tried balancing the prop?

54c180 wrote:Yikes ...
Where do you buy the bulkheads and how much$$
Poor design, inadequate
There needs to be an upgrade on this installation ...
Have you tried balancing the prop?

The prop was dynamically balanced using the Vibrex system. Bulkheads purchased through Yingling. We are working on a warranty claim for the last one. The one before was warrantied. I think they are near $800/ea.

HI Forum, found this thread and felt the need to chime in. I am on my 2nd (3rd if count original) attaching plate and spinner support in under 400 hrs. Brand new blackmac on Bonanza N35 with polished spinner (D7587), From my experience the support is the culprit. It seems to be too soft for the job, I have thousands of GA hours and done my share of prop/spinner work and never had this problem with older McCauley supports. The newer McCauley support is softer than previous supports I have worked with. I shim and load the spinner as usual, visually inspect for wobble and feel for vibration in flight (will dynamic balance this time). Both times around 150 hrs of flight the side of the support tears in flight and rattles away until I land. The attaching plate takes a beating in the process and develops a small crack near the hub which eventually extends outward. I also pulled the prop around 100 hrs ago to replace prop-shaft seal and there was signs of the support spinning on the hub and I am boggled as to how that happens.

The one on my MAULE is great.
I feel your pain.

OregonMaule wrote:The one on my MAULE is great.
I feel your pain.

Glad to see you posting a bit more Rob. I've missed you. Haha.