Cold Cylinder

Submitted by Anonymous on

Forums: 

From: jwilless [at] itd-nc.com <jwilless [at] itd-nc.com>
Sender: <marv [at] lancaironline.net>
Subject: Cold Cylinder
Date: Sun, 20 Jul 2014 17:03:12 -0400
To: <lml [at] lancaironline.net>
I have a Lancair ESP with a TSIO-550. Engine is very rough and low on power with #3 cylinder cold (100 degrees or more) on cht and egt while ROP. In cruise everything returns to normal if I go LOP. 

The injector o-rings looked okay when I inspected them. I sprayed the nozzle out pretty good with brake cleaner and shot a good amount of fuel out the spider and line. The injector is clean.

Cylinder #3 acts normal at idle and run up. At full takeoff power the engine stumbles as #3 goes cold. 

I've already done a visual inspection of all the clamps and couplings and conducted a soapy water soapy water test of the intake system.

There is a definite correlation between RPM and #3 going cold. Under about 2450 rpm ROP, #3 was smooth but a good 70 degrees colder than usual. When switching to LOP, #3 CHT comes right up in line with the other cylinders as normal and I can increase the rpm. When #3 get's rough, egt drops lock a rock. 

I tried using the high pressure fuel boost and modulating the flow with the mixture for a full rich condition but #3 stayed pretty cold. 

Mags checked out in all phases ROP and LOP. 

The #3 valves looked good with the scope and the compression was 72/80. The top plug looked a bit oily when I pulled it. 
Data can be viewed here. 


--

Thanks, Justin 

Cold Cylinder

Submitted by Anonymous on

From: Robert R Pastusek <rpastusek [at] htii.com>
Subject: FW: [LML] Cold Cylinder
Date: Mon, 21 Jul 2014 03:06:59 +0000
To: lml [at] lancaironline.net <lml [at] lancaironline.net>
Message Header


Undecoded Message

Justin,



At 5 hours of total time, my TSIO-550 developed a definite miss at high power/RPM. It would smooth out a bit if leaned, but the EGT and cylinder temp on #4 were definitely low at anything above about 2000 RPM. Engine idled smooth as silk; mag check at 1700
RPM totally good.

 

Short version of a long story: The valves on this engine have two springs, and the inner spring had broken, allowing
the #4 exhaust valve to “float” at higher RPM. I won’t tell you what all we tried to identify the problem, but it was “exhaustive.” The broken spring was not visible/could not be determined by just looking the cylinder. I found it by poking between the coils
of the outer spring with a piece of wire to determine that something inside was loose/moving around…and should not be…

 

Once the problem was identified, Ed Smith flew up with a home-made tool to compress the valve spring and remove the keepers.
He also brought a new spring (on a Saturday). Once the parts arrived, it 
was less than two hours to have it up and running….but the diagnosis went the better part of two weeks.

 

Check this as a possibility, and I REALLY 
HOPE you find the problem more quickly than I did mine!

 

Bob

 

From: Lancair
Mailing List [lml [at] lancaironline.net]">mailto:lml [at] lancaironline.net] On Behalf Of jwilless [at] itd-nc.com

Sent: Sunday, July 20, 2014 5:03 PM

To: Lancair Mailing List

Subject: [LML] Cold Cylinder

 

I have a Lancair ESP with a TSIO-550. Engine is very rough and low on power with #3 cylinder cold (100 degrees or more) on cht and egt while ROP. In cruise everything returns
to normal if I go LOP. 

 

The injector o-rings looked okay when I inspected them. I sprayed the nozzle out pretty good with brake cleaner and shot a good amount of fuel out the spider and line. The injector
is clean.

 

Cylinder #3 acts normal at idle and run up. At full takeoff power the engine stumbles as #3 goes cold. 

 

I've already done a visual inspection of all the clamps and couplings and conducted a soapy water soapy water test of the intake system.

 

There is a definite correlation between RPM and #3 going cold. Under about 2450 rpm ROP, #3 was smooth but a good 70 degrees colder than usual. When switching to LOP, #3 CHT
comes right up in line with the other cylinders as normal and I can increase the rpm. When #3 get's rough, egt drops lock a rock. 

 

I tried using the high pressure fuel boost and modulating the flow with the mixture for a full rich condition but #3 stayed pretty cold. 

 

Mags checked out in all phases ROP and LOP. 

 

The #3 valves looked good with the scope and the compression was 72/80. The top plug looked a bit oily when I pulled it. 

 

Data can be viewed here. 

 

 

--

Thanks, Justin 

Cold Cylinder

Submitted by Anonymous on

From: Janie & Ed Smith <2luv2fly [at] cox.net>
Sender: <marv [at] lancaironline.net>
Subject: [LML] Cold Cylinder
Date: Mon, 21 Jul 2014 07:25:57 -0400
To: <lml [at] lancaironline.net>
Message Header


Undecoded Message

Justin,

 

I would suspect a broken valve spring.  Check with Bob Pastusek.

 

Tailwinds,

 

Ed Smith

Chesapeake,VA

 

From: Lancair Mailing List [lml [at] lancaironline.net]">mailto:lml [at] lancaironline.net] On Behalf Of jwilless [at] itd-nc.com
Sent: Sunday, July 20, 2014 5:03 PM
To: Lancair Mailing List
Subject: [LML] Cold Cylinder

 

I have a Lancair ESP with a TSIO-550. Engine is very rough and low on power with #3 cylinder cold (100 degrees or more) on cht and egt while ROP. In cruise everything returns to normal if I go LOP. 

 

The injector o-rings looked okay when I inspected them. I sprayed the nozzle out pretty good with brake cleaner and shot a good amount of fuel out the spider and line. The injector is clean.

 

Cylinder #3 acts normal at idle and run up. At full takeoff power the engine stumbles as #3 goes cold. 

 

I've already done a visual inspection of all the clamps and couplings and conducted a soapy water soapy water test of the intake system.

 

There is a definite correlation between RPM and #3 going cold. Under about 2450 rpm ROP, #3 was smooth but a good 70 degrees colder than usual. When switching to LOP, #3 CHT comes right up in line with the other cylinders as normal and I can increase the rpm. When #3 get's rough, egt drops lock a rock. 

 

I tried using the high pressure fuel boost and modulating the flow with the mixture for a full rich condition but #3 stayed pretty cold. 

 

Mags checked out in all phases ROP and LOP. 

 

The #3 valves looked good with the scope and the compression was 72/80. The top plug looked a bit oily when I pulled it. 

 

Data can be viewed here. 

 

 

--

Thanks, JustinÂ