IO-540 mystery

On 8/27/2007 10:41:13 PM, The Visitor wrote:

Okay, but there is an "idle mixture" setting to check out.
On my cont, it is about the spider.

I had a problem with an Continental IO-520 engine quitting after roll-out
that turned out to be an idle mixture problem, even with the mixture control
set to full rich at landing. Note to Paul that this setting was adjusted
somewhere within the fuel system at the engine (spider?) and did not have to
do with the mixture control.

--
Peter

"Paul Tomblin" wrote in message
...
Our club's PA32R-300 has an IO-540 with lots and lots of hours on it.
After 20+ years, at this year's annual the compression was down a few
pounds on a couple of the cylinders, and the mechanic said he really has
his doubts about it passing next year's annual. That might be
significant, or it might not.

Twice this year, while people have been flight training in it (I was doing
a BFR this spring, another pilot was checking out in the plane for the
first time a few weeks ago), the engine has been running fine and on
rollout afterwards the engine died and couldn't be restarting. Both times
it was after doing some air-work (stalls, steep turns, etc) and then a
couple of touch and goes. Nobody has had any problems in a normal point
to point flight, although we've had the normal problems with hot starting
that's endemic to fuel injected aviation engines.

Many of the replies here are confusing the operation of the Continental fuel
injection with the Bendix system on the Lyc. The delivery fuel pressure and
flow rate in the Bendix system is controlled by the servo unit, no external
regulators or fuel return to tank. The servo measures the impact of the
entering air and adjusts the fuel flow rate accordingly.

An idle speed a little higher than normal might stop the dying on rollout
and a slightly richer idle mixture might help dissipate vapor that could be
forming in the heat of the day.

"Ronnie" wrote in message news

I fully, completely, agree with your comment about it being hard
to taxi when one quits during roll-out. Hopefully the turn you need
to make onto the taxiway is to the side that quit!

Ronnie


You could always do a 270° turn...

;-)

Well put and true. I was. My experience is with Continentals. I didn't
realize the extent of the differences.

John

John Kunkel wrote:

Many of the replies here are confusing the operation of the Continental fuel
injection with the Bendix system on the Lyc. The delivery fuel pressure and
flow rate in the Bendix system is controlled by the servo unit, no external
regulators or fuel return to tank. The servo measures the impact of the
entering air and adjusts the fuel flow rate accordingly.

An idle speed a little higher than normal might stop the dying on rollout
and a slightly richer idle mixture might help dissipate vapor that could be
forming in the heat of the day.

"Paul Tomblin" wrote in message
...
Our club's PA32R-300 has an IO-540 with lots and lots of hours on it.
After 20+ years, at this year's annual the compression was down a few
pounds on a couple of the cylinders, and the mechanic said he really has
his doubts about it passing next year's annual. That might be
significant, or it might not.

Twice this year, while people have been flight training in it (I was doing
a BFR this spring, another pilot was checking out in the plane for the
first time a few weeks ago), the engine has been running fine and on
rollout afterwards the engine died and couldn't be restarting. Both times
it was after doing some air-work (stalls, steep turns, etc) and then a
couple of touch and goes. Nobody has had any problems in a normal point
to point flight, although we've had the normal problems with hot starting
that's endemic to fuel injected aviation engines.

The last time it happened, the engine died at the airport where our
mechanic is based, and he pulled the plugs and said they weren't fouled
and they were dry (so the problem restarting wasn't that he flooded it).
Based on a suggestion here, I had them check the fuel pressure, and it
seems fine. Could it be vapour lock? Any other suggestions?

If it was really hot and you have a low idle or the idle is running too
rich...it's most likely vapor lock.

Kobra

http://www.lycoming.com/support/trou...ting-Guide.pdf

The last section of this guide is the Bendix fuel injection trouble shooting
guide. See page 22.

Jim

In a previous article, (Paul Tomblin) said:
Twice this year, while people have been flight training in it (I was doing
a BFR this spring, another pilot was checking out in the plane for the
first time a few weeks ago), the engine has been running fine and on
rollout afterwards the engine died and couldn't be restarting. Both times
it was after doing some air-work (stalls, steep turns, etc) and then a
couple of touch and goes. Nobody has had any problems in a normal point
to point flight, although we've had the normal problems with hot starting
that's endemic to fuel injected aviation engines.

Just heard back from the mechanic. He says the magnetos are shot. This
is a single drive dual mag, and it's going to cost $1450 for the part.
Yikes. Hope it fixes it.

--
Paul Tomblin http://blog.xcski.com/
Reliability went through the floor, tunnelled its way to the centre of
the Earth, and perished in the magma.
-- Saundo

Ewww... Bummer What's an overhauled exchange cost for that big "lunch
box" mag?
Jim

"Paul Tomblin" wrote in message
...
In a previous article, (Paul Tomblin) said:
Twice this year, while people have been flight training in it (I was
doing
a BFR this spring, another pilot was checking out in the plane for the
first time a few weeks ago), the engine has been running fine and on
rollout afterwards the engine died and couldn't be restarting. Both
times
it was after doing some air-work (stalls, steep turns, etc) and then a
couple of touch and goes. Nobody has had any problems in a normal point
to point flight, although we've had the normal problems with hot starting
that's endemic to fuel injected aviation engines.

Just heard back from the mechanic. He says the magnetos are shot. This
is a single drive dual mag, and it's going to cost $1450 for the part.
Yikes. Hope it fixes it.

--
Paul Tomblin http://blog.xcski.com/
Reliability went through the floor, tunnelled its way to the centre of
the Earth, and perished in the magma.
-- Saundo