Ignition Harness NIGHTMARE!

[MikeOH]

1970 M20F, TCM/Bendix mags: S4LN-200/204, 3/4"-20 RHM38E plugs.

Ordered a new Kelly Aerospace harness P/N: KA12630.  The attached photo shows the problem between my old and new: the insulators in the cap are too high and prevent the cover from closing flush with the mag housing.  I called Kelly Aero this morning and spoke the their tech service guy who told me he answers this question all the time!  His answer: The mag design was changed in the early seventies, so use as is, just put some RTV on the gap between the cover and mag housing

This doesn't sound right to me. BWTHDIK?

I ordered from Kelly because I could not find the Champion M2360 in stock.  Does anyone KNOW if the Champion harness looks like my old one, or will I have the same issue?

And, just 'cause I'm a glutton for punishment...is Spruce going to take the harness back?  (I know auto parts stores will NOT take electrical items back)

[Janat83]

I don't know about champion harness but Aircraft spruce might charge restocking fee, or they might not change it, but you can sell them here or on FB groups they'll sell fast.

I hope your issue will be solved asap. 

[Shadrach]

I think that’s terrible advice. I’m pretty sure that harness will fit but it will be a PITA to get everything fully seated. My mags date back to 67 and have a harness made in this century.  One of the leads is a Kelly product purchased when a 90° Elbow failed.  I recall it being frustrating to reinstall

Edited August 31, 2021 by Shadrach

[KSMooniac]

I try never to buy any Kelly products. I'd return it and demand a full refund since it doesn't fit the application they advertised.

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[Shadrach]

21 minutes ago, KSMooniac said:

I try never to buy any Kelly products. I'd return it and demand a full refund since it doesn't fit the application they advertised.

Sent from my LM-V405 using Tapatalk
 

What’s the alternative? Champion no longer makes Bendix harnesses.

[KSMooniac]

What’s the alternative? Champion no longer makes Bendix harnesses.

Unfortunately I do not know... I'm planning to switch to Electroair pretty soon, hopefully before I need a new harness.

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[MikeOH]

7 minutes ago, Shadrach said:

What’s the alternative? Champion no longer makes Bendix harnesses.

Oh, that's just great!

So, I have no choice but to make the Kelly POS work???

[Shadrach]

Just now, MikeOH said:

Oh, that's just great!

So, I have no choice but to make the Kelly POS work???

Maybe you see something I don’t.
https://www.championaerospace.com/pdfs/AV-14.pdf

Spruce sells a Bendix harness kit but it is not a certified harness. They suggest that some of their harnesses have been installed with a field approval. 

 

[carusoam]

Something to look into…

With the electronic mags coming in…. A new (to us) mag harness company has showed up on the scene…

https://www.newhorizonsmaggieaircraftignitionsystems.com/maggie-ignition

There was something about the old wire harness guys that left the door open for the Maggie system…

I don’t think the silicone solution would match the normal certified airplane standards… that barely meets the experimental standards by the sound of it…

PP thoughts only, not a mechanic…

Best regards,

-a-

[MikeOH]

30 minutes ago, Shadrach said:

What’s the alternative? Champion no longer makes Bendix harnesses.

@Shadrach

I just downloaded this.  Are you sure they are discontinued?

 

[N201MKTurbo]

I just ordered a harness set from Maggie A mom and pop harness business (PMA).

They were cheaper than the big guys and she called me 4 times after I ordered it just to make sure we were all on the same page.
 

I’ll let you know how it turns out.

BTW for a 56 Cessna, not a Mooney.

Edited August 31, 2021 by N201MKTurbo

[carusoam]

Let’s see if @HoJo87 the Maggie Ignition guy is around… it’s been about a year since they posted last…

Best regards,

-a-

[mike20papa]

Ask https://www.aircraftmagnetoservice.net

They are super to deal with.

[DV8Pilot]

1 hour ago, N201MKTurbo said:

I just ordered a harness set from Maggy. A mom and pop harness business (PMA).

They we’re cheaper than the big guys and she called me 4 times after I ordered it just to make sure we were all on the same page.
 

I’ll let you know how it turns out.

BTW for a 56 Cessna, not a Mooney.

Another vote for Maggie harnesses. Fast and great customer service. Really nice product too. I installed on my Bendix Sl4ns with no problems.

[hammdo]

Ditto on Maggie...

-Don

[Jeph357]

Plus one for Maggie. Fast, available for questions as needed

[Shadrach]

11 hours ago, MikeOH said:

@Shadrach

I just downloaded this.  Are you sure they are discontinued?

 

I have had no luck finding a new harness that is physically available for sale that is not made by Kelly Aerospace.  I had not heard of Maggie and will be investigating that option as mine is starting to look a little tired.

[Shadrach]

14 hours ago, mike20papa said:

Ask https://www.aircraftmagnetoservice.net

They are super to deal with.

They make ignition harnesses?

Edited August 31, 2021 by Shadrach

[Ragsf15e]

13 hours ago, N201MKTurbo said:

I just ordered a harness set from Maggie A mom and pop harness business (PMA).

They were cheaper than the big guys and she called me 4 times after I ordered it just to make sure we were all on the same page.
 

I’ll let you know how it turns out.

BTW for a 56 Cessna, not a Mooney.

Another plus for Maggie.  Works fine so far.  Easy to deal with.  As a bonus, they’ll do one side instead of having to order both if you’re getting an electronic mag on one side.

[bfreelove]

 

From TCM CSB668

"The edges of the ignition harness attachment plate are not required to mount tight (flush with) to the magneto distributor housing: Tests of sample conforming parts show complete ball-cone seat contact made at 12 in-lbs. Additional torque application did not improve contact on any of the brands tested."

http://www.tcmlink.com/pdf2/csb668.pdf

 

[mike20papa]

 Great info!  I am sure lots of mechanics torque the hell out of the screws thinking the cap will eventually mate.  This quote I find interesting, "These harnesses are manufactured and distributed under PMA approval without TCM knowledge or approval."  So, anybody .. does TCM/Bendix sell a harness that does "fit".

[MikeOH]

4 hours ago, bfreelove said:

 

From TCM CSB668

"The edges of the ignition harness attachment plate are not required to mount tight (flush with) to the magneto distributor housing: Tests of sample conforming parts show complete ball-cone seat contact made at 12 in-lbs. Additional torque application did not improve contact on any of the brands tested."

http://www.tcmlink.com/pdf2/csb668.pdf

 

@bfreelove

WOW!

THAT was quite the pull!  Thank you very much.

So, it looks like the guy at Kelly was spot on.  I just could not believe the gap was in any way OK.  It still bugs me...seems like as the rubber ages the cover is going to get loose.

[MikeOH]

4 hours ago, mike20papa said:

  So, anybody .. does TCM/Bendix sell a harness that does "fit".

Exactly what I'd like to know, too!

I found stock at Spruce for the 5/8" plug Champion Harness (mine is presently for 3/4" plugs, RHM38E).  I was going to go take a look tomorrow and see if it looks like my old plate.  If so, I may just buy a set of REM38Es and go that route.

[Shadrach]

28 minutes ago, MikeOH said:

@bfreelove

WOW!

THAT was quite the pull!  Thank you very much.

So, it looks like the guy at Kelly was spot on.  I just could not believe the gap was in any way OK.  It still bugs me...seems like as the rubber ages the cover is going to get loose.

I have had the same mags on my plane since 1967. The current harness was installed at overhaul in 2001. The attachment plate has always mounted flush.

[MikeOH]

1 minute ago, Shadrach said:

I have had the same mags on my plane since 1967. The current harness was installed at overhaul in 2001. The attachment plate has always mounted flush.

Do you know what brand your current harness is?  Not sure what my old one was but, like yours, it mounted flush.  I'd still really like a new one to do the same!  (I'm trying to figure out if this is dependent on if it's Champion/Slick vs. Kelly, or something else)