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Date: Mon, 20 Aug 2012 18:44:42 -0400
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Subject: =?windows-1252?Q?Re=3A_=5BLML=5D_Pictures_from_Cylinder_no2=85?=
 =?windows-1252?Q?=2E=2Ewhat_the_heck=3F=3F?=
From: Paul Miller <pjdmiller@gmail.com>
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Hi Ronald, I agree with another poster, I don't really see the issue =
here.   If an EGT starts going wild I wouldn't pull a jug and I =
certainly wouldn't change the engine.  Deposits are normally found so =
that isn't a reason either.    TCM has a large section on checking for =
problems starting with the EGT probes and going from there.  To pull =
cylinders first and swap out to an Allison makes less sense than trying =
to verify the EGT issue in the first place.  Swapping a probe comes to =
mind and is somewhat less expensive and doesn't require surgery on the =
patient.  And they recommended pulling cylinders based on what?  And how =
many hours on the engine because now you have to be absolutely sure the =
crankcase halves don't fret and cause more problems.  Been there, done =
that.  Make sure they check the SBs on that subject before you fly =
again.

Paul
Legacy (and two dogs with lots of brown deposits)
On 2012-08-19, at 9:36 AM, Ronald STEVENS <Ronald@sdc.com> wrote:

> Hello guys
>=20
> Well, this is one the reasons why I am thinking of replacing my engine =
with a turbine lol
>=20
> Anyway, we are scratching our heads here. We found (looks like lead) =
deposits inside the cylinder and on top of the pistons. It is pretty =
soft, some parts are harder (probably baked) and you can actually take a =
harder sponge and start cleaning lol
>=20
> But why?? Why did this happened?? I mean I am thinking I am always =
driving my engine according to the 'gospels', Full rich in climb and =
take off, never over powering (using MAP 31-34 in climb), then level =
off, go back to MAP29, lean to 16.5, bump it up to MAP31-32 with approx. =
18GPH/2500 RPM
>=20
> Always checking for CHT, (cruise temps are approx. 370), TIT=3D1610
>=20
> So.....then suddenly my EGT (not CHT) starting to act up, and showing =
a HOT warning, me adding mixture to full rich, EGT back to normal, this =
happened twice on the same cylinder, so I requested a borescope and =
found this.....so we pulled the jug.
>=20
> Now I can pull them all, clean them all, and wait for the next time?? =
Why could something like this happen? (I even heard someone telling me =
that I was leaning too much??)
>=20
> Any idea ??
>=20
> Thanks -- Ronald
>=20
> ps Pict 3 showed some of the stuff that we were able to scrape off, =
and in the upper left corner you see the hot spots, they are colored but =
the 'skin' feels the same, so it looks like material was coming off or =
burned in, but it is not, it is the deposit on top.=20
>=20