Group Poll: How many hours between mag overhauls?

Our Mooney has a 500 hour recurring AD for inspecting the Impulse
Coupler. While they have it off they will inspect the points and
condensers and replace worn ones. Our left mag was out of time by 5
degrees so they had to remove the magneto anyway.

Jon Kraus
PP-ASEL-IA
'79 Mooney 201

Jim Burns wrote:

To the group: At how many hours do you rebuild or replace your mags? or do
you wait for a problem to arise first?

Jim

Jim Burns wrote:
: To the group: At how many hours do you rebuild or replace your mags? or do
: you wait for a problem to arise first?

My airplane has Bendix mags, which as Jon pointed out have a recurring
AD for impulse coupling inspection. I think it's every 400 hours, though, but
I can't remember. So, every 400 hours the impulse mag gets an internal
inspection. I have the non-impulse mag inspected at the same time, although
not strictly required. It makes me feel better while I'm flying night IMC over
the Chesapeake Bay. Most of the time nothing needs repair, although the
first time we found some "superceded" parts that were replaced.

If I notice different mag drops and the plugs are OK I have the mags looked
at, as the timing may have changed. Every 100 hours I check mag to engine
timing when I clean the plugs.

Keeping the mags well tuned makes the engine start much easier, too.
--
Aaron C.

To the group: At how many hours do you rebuild or replace your mags? or do
you wait for a problem to arise first?

Jim

I have the mags (Bendix) overhauled at the same time the impulse couplings
get done. (Seneca)
"Jim Burns" wrote in message
...
To the group: At how many hours do you rebuild or replace your mags? or
do
you wait for a problem to arise first?

Jim

Jim Burns wrote:
To the group: At how many hours do you rebuild or replace your mags?
or do
you wait for a problem to arise first?

When the left comes off for the impulse coupler inspection, I have
both sent over to the accesory shop. Rather than having them
overhauled, I have the shop "inspect and repair as necessary". It's
much less expensive than an overhaul. If the mags are in good shape, I
see no need to go the full overhaul route and replace a bunch of parts
that are working just fine. Most of the time, the mags come back with
little or no work having been done. If they were really getting rough,
the shop would let me know and I'd OK an overhaul. My current set of
(Bendix) mags went about 1200 hrs. between overhauls.


John Galban=====N4BQ (PA28-180)

Jim Burns wrote:
To the group: At how many hours do you rebuild or replace your mags? or do
you wait for a problem to arise first?

Jim


500 hours. Usually, one needs some parts and the other needs to be
replaced. Slick mags in a Cherokee 140.

Mike

I replaced the Slick mags on my Husky's Lycoming O-360 after 2000
hours, though the plane didn't run any better with the new ones. Seemed
like it was time for new ones. They work great too. Mechanic managed to
miss-time them at first go around. Had trouble with his buzz box. It's
tight back there, hard to adjust them.

On Thu, 21 Apr 2005 00:51:16 GMT, Mike Spera
wrote:

Jim Burns wrote:
To the group: At how many hours do you rebuild or replace your mags? or do
you wait for a problem to arise first?

Jim


500 hours. Usually, one needs some parts and the other needs to be
replaced. Slick mags in a Cherokee 140.


I've put a 1000 on them and I'd have to dig out the log books but I
believe they were new with the engine. That'd make about 1300
currently. Still workin' good.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
Mike

"Jim Burns" wrote in message ...
To the group: At how many hours do you rebuild or replace your mags? or do
you wait for a problem to arise first?

Jim


I have them opened every 500 hours in my Mooney. I don't have the AD
because my mags were replaced. However, I've never actually O/H'd
them. I have them opened, inspected and replace points, etc. The shop
has never found any issues worthy of an O/H. Figure 3-4 hours per mag.

-Robert

MAINTENANCE INTERVALS FOR ALL TCM AND BENDIX AIRCRAFT MAGNETOS
see SB643B
http://www.tcmlink.com/servicebulletins/index.cfm

i use 500 hr for bendix & slick for service
for Bendix D-2000 450 to 500 for service
jon