Cracked Spinner Cone - MX-7-160

Aerobatix · Post by **Aerobatix** » Sun Aug 10, 2008 7:02 am

During preflight noticed a significant crack in the spinner cone about 4" long starting at the front section of the prop blade cutout.

Pulled the spinner and the internal support cone. The backplate is still attached since its behind the prop. Can I fly with the spinner cone off?

Where can I get a new spinner cone for the best price and what should I expect to pay? Anyone have a good condition used one for sale?

Appreciate any help!!

Rob

rjb · Post by **rjb** » Sun Aug 10, 2008 7:20 am

In a seminar on ramp checks given by the local FSDO, the speaker was adamant that an aircraft was not airworthy with a cracked spinner, a spinner that had a crack stop drilled, or without its spinner. (He did concede that the POH could conceivably be written so that the spinner was optional.)

210TC · Post by **210TC** » Sun Aug 10, 2008 7:43 am

I think rjb is correct. Ramp check could spell bad news.
Don't tell anyone I wrote this....I would fly without and watch the temps as this could effect the flow of air. I have seen at least a 100 aircraft operated without spinners over the years. I have also seen dozens of spinners welded from the inside. I have never done this and do not know if it is allowed.
My theory would be..fix what caused the crack in the first place then find a welder that welds aluminum EVERY day, preheat the spinner in an oven and place a really small bead on the inside of the spinner. Install and inspect,inspect and reinspect. Meanwhile eye's open for used one.

Aerobatix · Post by **Aerobatix** » Sun Aug 10, 2008 8:35 am

I plan to put the spinner cone and support ring in the back of the plane IF I need to fly it before I can get a replacement. That way I would "hope" to get through a ramp check by stating we are on our way home and discovered the problem at our last fuel stop.

Anyone know the best source for a replacement spinner?????

rjb · Post by **rjb** » Sun Aug 10, 2008 8:50 am

I suggest you check out backcountryboyscout posts at backcountrypilot.org and ask there as well about a used spinner.

a64pilot · Post by **a64pilot** » Sun Aug 10, 2008 5:25 pm

Long story short. I watched an ATL FSDO inspector crawl all over an ATL ACO test pilot when he was caught flying an FAA rented C-310 with the spinner removed. The Atl FAA test pilot found a crack in the spinner in Savannah at Gulfstream, so he removed it. The inspector turned three shades of colors when he was told to go away. The FSDO guys think a WHOLE lot of that spinner. I can tell you don't worry about temps, there will be no difference, and you won't be able to tell it's not there. I have no idea why they are so anal about spinners, but trust me they are. Don't weld it, buy a new one.

maules.com · Post by **maules.com** » Sun Aug 10, 2008 6:28 pm

Maule MX7-160's had spinner problems.
The middle bulkhead was prone to cracking at the prop bolt holes and because it is fixed pitch the spinners were not getting pulled at each annual as they should be. Possibly this was the start of your cracking.
When Maule introduced the MX7-180A and 160, they ended up short of middle bulheads for the 180 and Sensenich and Maule decided to ream/drill out the holes of the 160 bulkheads to accomodate the 180 bolt size.
I had to call warranty on many of these bulkheads in the past and Sensenich responded very well with replacement.If your mounting screw holes are ovalled or wallowed out atall thes can cause the cracking.

Aerobatix · Post by **Aerobatix** » Mon Aug 11, 2008 4:32 am

Jeremy,

On my Maule the bulkhead has no bolts/screws to attach the cone to the bulkhead. The only screws are those that attach the spinner cone to the backplate.

Does this seem correct? I checked the Seinsinich website and I did notice most of the spinners had holes for mounting the bulkhead to the cone in addition to the backplate.

Thanks!

maules.com · Post by **maules.com** » Mon Aug 11, 2008 1:52 pm

I have not looked at an MX7-160 in some time so cannot properly remember the screw pattern used.
I have here a 1993 MX7-180A (fixed pitch) and a 1999 MXT7-180A (fp) and they both have 12 fasteners around the backing plate and 6 fasteners around the support bukhead.

Aerobatix · Post by **Aerobatix** » Mon Aug 11, 2008 1:57 pm

I ordered a complete new spinner kit from Sensinich today. Total cost was $637 and this spinner has screws for the middle bulkhead as well as the backplate. Should have it on Thursday!!

a64pilot · Post by **a64pilot** » Mon Aug 11, 2008 3:16 pm

I think you will come out better in the long run. I'm afraid of welding spinners, yes it's done, but I'm not sure it should be. If nothing else it throws the balance off.
If your up this way on a weekend I'll balance the prop if you want to. You buy the beer.

AK Mauler · Post by **AK Mauler** » Mon Aug 11, 2008 7:09 pm

I have the MX7-180 fixed pitch, any idea on the cost for just the spinner cone? or do you have to purchase the whole kit with spacer and bulkhead?

Aerobatix · Post by **Aerobatix** » Tue Aug 12, 2008 6:05 am

check out the sensinich.com website for spinner prices. I believe the spinner cone alone was $395. They were very helpful when I called to speak with them. Good service, fair price and same day shipping!

Aerobatix · Post by **Aerobatix** » Tue Aug 12, 2008 6:08 am

a64pilot wrote:I think you will come out better in the long run. I'm afraid of welding spinners, yes it's done, but I'm not sure it should be. If nothing else it throws the balance off.
If your up this way on a weekend I'll balance the prop if you want to. You buy the beer.

A64 - I'd like to take you up on the prop balance offer. I'll check in with you once we're back in the air!!!

Thanks,

Rob

Cracked Spinner Cone - MX-7-160

Cracked Spinner Cone - MX-7-160

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