912 cracked stacks...ceramic coated, new source?

[bruceschimmel]

Once again, the stacks on my 912 are cracked.

A three-year-old part, straight from the factory: treated with black ceramic coating. (And, yeah, I had the prop balanced.)

I have not yet seen the pipes myself, so I don't know if only the ceramic is cracked or if the metal underneath is also compromised. (I had not previously seen any stains on the wrapping to suggest that exhaust is escaping.)

Is is possible for the ceramic on coated pipes to crack and the pipe underneath still be quite viable –- as strong as ever?

And assuming the pipes underneath the ceramic *are* cracked, who would repair them?

And if they can not be repaired, where would you make up a new set -- now that the factory is closed?

many thx, Bruce

[John Lawton]

Is is possible for the ceramic on coated pipes to crack and the pipe underneath still be quite viable –- as strong as ever?

Hey Bruce,

There's one quick way to tell. If you have a shop vac that also will blow air (usually you have to switch the hose to the outlet port) you can duct tape the shop vac hose to the stack and blow low pressure air into it. Take a spray bottle with soap/water solution and mist the areas where the cracks have appeared. If it's cracked all the way through the soap will bubble up as the air escapes through the cracks. If not, it's likely that just the ceramic is cracked.

Hope it helps!

Regards,

John Lawton
Whitwell, TN (TN89)
Ximango #135