What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Lean of Peak Problems with Dual P-Mags

A little off the original topic here, but very useful and applicable information. While we're on the subject... I'm not a builder. One day I will be, but in the meantime, I plan to learn everything I possibly can by working on my bird. On that note, what is the approved solution for aviation "heat shrink" and the like, once you've crimped/soldered/butted your wires together? I ask specifically because I now have exposed connections that I uncovered while tracing my tach problem. They were covered in some kind of balled up rubbery electrical tape that might have done the trick but was at the very least unsightly. I'm wondering how people get those beautiful finishing touches like in Jim's last photo. See attached picture to get an idea of what I'm working with.
 

Attachments

  • Tach Wires - 1.jpeg
    Tach Wires - 1.jpeg
    314.7 KB · Views: 220
...what is the approved solution for aviation "heat shrink" and the like, once you've crimped/soldered/butted your wires together? ...
Two solutions: 1) slide some heat shrink on the finished connection like you have in the photo; 2) put the heat shrink on before finishing the connection and make the connection in a straight line.

If you want to learn a lot about wiring best practices, spend some time on this site: http://www.aeroelectric.com - there are a lot of hints and tips there.
 
A little off the original topic here, but very useful and applicable information. While we're on the subject... I'm not a builder. One day I will be,... I'm wondering how people get those beautiful finishing touches like in Jim's last photo. See attached picture to get an idea of what I'm working with.

Those are awful splices. You can slide some shrink tubing over them, but note how pulling the wire just splits the tube and stresses the wire across a 90 degree bend.

Want to be a builder? Time to start your tool investment. The standard butt splice is an AMP PIDG. You'll invest in the correct ratcheting crimp tool, which guarantees the correct degree of crimp. A PIDG does not require shrink tubing. Here is one popular source: https://www.steinair.com/product-category/terminals-tape/

Shrink tubing comes in many varieties. The good stuff is 3-to-1 or 4-to-1 shrink, lined with heat melt adhesive, as it significantly improves fatigue performance and seals it against the elements. There is also clear, no adhesive, which makes for nice labels, and lots of specialty types:

https://www.delcity.net/store/Shrink-Tube-&-Tape/

If the shrink covered connection is preferred, use a bare, brazed barrel terminal:

https://www.delcity.net/store/Non!Insulated-Butt-Connectors/p_801870.h_801871
.
 
If you absolutely have to solder wires, I recommend you use one of these Solder Sleeves, in the correct size. Used correctly not only do they make a good electrical connection, they provide mechanical support.

You can also splice them together with one of these Wire Overlap Connector. Make sure you get the correct hex key for it. They are a bit pricey but well worth the extra cost.

:cool:
 
Last edited:
Ok I got it, some people just want to make it appear difficult :D -

1. Why not just solder the wire - with care & the correct technique the just very end of the wires can be soldered without solder wicking much at all.
2. Each P-Mag has a p-clip fitted & my method is to cable tie the wire loom (usually 3-4 wires) to it. That makes it easier to completely remove the mag for annual (100hr) inspections- much easier than trying to remove the cap screw in situation.
3. IMO securing the wires to the p clip close as possible to the connector will give all the support needed & therefore mitigate the risk of wire breakage. It’s not rocket science :)
It appears in an earlier post that an OP wire may have been loose because the wire was not in place properly to start with - the slotted screws need to be undone first before inserting the wires ( I’ve made that mistake, once) , do the screws up & then do the standard ‘pull test’. 650+ hrs & many P-Mag installs later without issues since.
 
Last edited:
If you want to learn a lot about wiring best practices, spend some time on this site: http://www.aeroelectric.com - there are a lot of hints and tips there.

This site is a gold mine! Thanks for sharing!

...

The standard butt splice is an AMP PIDG. You'll invest in the correct ratcheting crimp tool, which guarantees the correct degree of crimp. A PIDG does not require shrink tubing. Here is one popular source: https://www.steinair.com/product-category/terminals-tape/

Shrink tubing comes in many varieties. The good stuff is 3-to-1 or 4-to-1 shrink, lined with heat melt adhesive, as it significantly improves fatigue performance and seals it against the elements. There is also clear, no adhesive, which makes for nice labels, and lots of specialty types:

https://www.delcity.net/store/Shrink-Tube-&-Tape/

If the shrink covered connection is preferred, use a bare, brazed barrel terminal:

https://www.delcity.net/store/Non!Insulated-Butt-Connectors/p_801870.h_801871
.

Perfect. Exactly what I needed to know. Thank you!

If you absolutely have to solder wires, I recommend you use one of these Solder Sleeves, in the correct size. Used correctly not only do they make a good electrical connection, they provide mechanical support.

You can also splice them together with one of these Wire Overlap Connector.

...

Thanks for the info!
 
Ok I got it, some people just want to make it appear difficult :D -

1. Why not just solder the wire - with care & the correct technique the just very end of the wires can be soldered without solder wicking much at all.
2. Each P-Mag has a p-clip fitted & my method is to cable tie the wire loom (usually 3-4 wires) to it. That makes it easier to completely remove the mag for annual (100hr) inspections- much easier than trying to remove the cap screw in situation.
3. IMO securing the wires to the p clip close as possible to the connector will give all the support needed & therefore mitigate the risk of wire breakage. It’s not rocket science :)
It appears in an earlier post that an OP wire may have been loose because the wire was not in place properly to start with - the slotted screws need to be undone first before inserting the wires ( I’ve made that mistake, once) , do the screws up & then do the standard ‘pull test’. 650+ hrs & many P-Mag installs later without issues since.

Do you have a picture you could possibly share? It sounds interesting but I'm having trouble visualizing your setup.
 
If you absolutely have to solder wires, I recommend you use one of these Solder Sleeves, in the correct size. Used correctly not only do they make a good electrical connection, they provide mechanical support.


:cool:

Hate to disagree but Solder sleeves are made for terminating the shield on shielded wire not joining wires.
 
Those are awful splices. You can slide some shrink tubing over them, but note how pulling the wire just splits the tube and stresses the wire across a 90 degree bend.

Want to be a builder? Time to start your tool investment. The standard butt splice is an AMP PIDG. You'll invest in the correct ratcheting crimp tool, which guarantees the correct degree of crimp. A PIDG does not require shrink tubing. Here is one popular source: https://www.steinair.com/product-category/terminals-tape/

Shrink tubing comes in many varieties. The good stuff is 3-to-1 or 4-to-1 shrink, lined with heat melt adhesive, as it significantly improves fatigue performance and seals it against the elements. There is also clear, no adhesive, which makes for nice labels, and lots of specialty types:

https://www.delcity.net/store/Shrink-Tube-&-Tape/

If the shrink covered connection is preferred, use a bare, brazed barrel terminal:

https://www.delcity.net/store/Non!Insulated-Butt-Connectors/p_801870.h_801871
.

To be more specific, crimp terminals should meet MS25036 specifications. Both Amp (TE) PIDG and Molex AVIKRIMP brands meet this specification. When I built my Rocket, the inspector actually asked the specific brands of my terminals.
 
To be more specific, crimp terminals should meet MS25036 specifications. Both Amp (TE) PIDG and Molex AVIKRIMP brands meet this specification.

Insulated ring terminals should meet MS25036. There are similar milspecs for other connection styles and for uninsulated terminals.
 
I have dual "P" mags with 9:1 pistons, performance cam, ventury cut seats, etc. I run BR9ES plugs, a bit cooler. NGK plugs of the same number, ie
BR8ES can come with screw on caps or solid caps. If the screw on caps get loose, it will cause radio noise, and burn areas on the plug end connector of the spark plug wire. Will run rough at altitude. Using the solid plug caps and new terminal ends, runs great!!

DAR Gary
 
Insulated ring terminals should meet MS25036. There are similar milspecs for other connection styles and for uninsulated terminals.
Righto, badly worded. I'm trying to point out that both PIDG and AVIKRIMP brands are acceptable for various terminals and that they meet milspecs.

Thanks, Vern
 
This video shows how to join wires together using "solder sleeves", the original design idea. :D

Ya Gotta love youtube...

https://www.youtube.com/watch?v=unxEdyW8RP8

Never seen a 'solder sleeve' called out for a splice repair in any document I've ever seen. On the other hand I have repaired a few bad/cold solder joints where this method was used for a CAN bus and a few other things.

Just the fact that it would take me 10x longer and 3 hands to do what an amp butt splice can do in seconds with 100% reliability is a good enough reason not to use it.
 
Last edited:
Just the fact that it would take me 10x longer and 3 hands to do what an amp butt splice can do in seconds with 100% reliability is a good enough reason not to use it.
FWIW I also prefer a butt splice but solder sleeves can and do work.

BTW, awesome "thread drift". :D
 
Last edited:
3 hands needed

...

Just the fact that it would take me 10x longer and 3 hands to do what an amp butt splice can do in seconds with 100% reliability is a good enough reason not to use it.
The 3 hands part is my main complaint - you think you have it stable, put the heat gun on, and it all moves.
 
E-Mag Install Manual

From the "Maintenance" section of the E-Mag manual:

Every annual or 100 hour inspection:

6. Examine control plug and coil plug connections. Tighten to 4-5 inch pounds. Verify there are no stray wire strands. Verify all control wires use the Adel clamp strain relief.

The control plug needs an eyes-on every time the cowl comes off, IMO. I have a short list of things like this I look at each time it does on mine. Just to be sure.

I like the ferrule idea...neat....clean...secure.

Rob S.
 
Back
Top