Van's Wiring Kit Crimp Failure

[bkc3921]

Was making some minor angle adjustments to the "engine ground to firewall" P-26 wire, from Van's wiring kit..and POP! ..off came the crimp. I am very easy on the wiring..gave the other end a slight tug..and POP!!..off it came also. My wiring guru and I stripped the heat shrink off..and the crimp "failed"..The wired should have been deformed in the crimping process..and they were not..I don't know for sure, but it almost seems like the wrong size crimping tool was used at the point of manufacture. These are the largest wires in the system. We will re-crimp and solder these connections.

Has anyone else had this problem?..I am very careful with the wiring, and the failure of the crimp was not due to unnecessary or unusual bending. I am now suspect of the other large wires in my system..i.e. starter and battery power, etc. ...Please let me know if this is a "normal" problem..Or I just have some bad ones...Thanks.

[Bob Axsom]

You should let Van's know of your problem even though I suspect someone from there will see this post - there is absolutely no doubt in my mind that every wire bundle that went through the process at the same time has the same problem.

For you there is no reasonable option but to redo these terminations. If you can isolate the problem to one wire gauge and terminal size and type then you only need to fix them. However, the process of determining that requires that you at least inspect a reasonable sample of the others.

Bob Axsom

[Ironflight]

Bob Collins reported on this sometime in the past year - he had several cables fall apart. If I recall correctly, Van's was notified and made aware of the problem, and it did affect a number of people. Might check Bob's blog - I know he talked about it!

Paul

[Danny7]

teh bob collins thread

http://www.vansairforce.com/communit...ad.php?t=56194

[noelf]

IIRC, Van issued a notice (SL or SB) on defective crimps on the large wires a few years ago. Was your wiring from a recent kit, or an "older" kit.

[Doug]

refer:
http://www.vansaircraft.com/pdf/batterycables.pdf

If your cables are outside the applicability of this notice - let Vans know!

I had to replace every one of these crimp lugs - I used heavier lugs typically found in large switchboards - I do not recall the manufacturer (perhaps Utilux).

When the lug is correctly swaged - the wire will yield rather than have the lug pull off, and given the size of this cable reasonably heavy duty equipment would be necessary.

If the lug can be removed by hand - it is seriously short of the mark.

BTW broken wire strands are indicative of overcrimping.

Doug Gray

[LettersFromFlyoverCountry]

I thought Van's would say something after the crimps fell off. They asked me not to say anything on any of the bulletin boards while they investigated (a request I agreed to), but I never saw or heard anything else on the subject, which was particularly troubling because all of the connectors that fell off, came off cables that I ordered months apart.

It's certainly up to them whether they want to issue a SB or not, but the much more important aspect of this is a reminder for us builders to get into the habit of checking ALL parts we're installing on the plane. We don't really need an SB to take action.

I'm now making all my own cables and doublechecking everything I've gotten from third parties. Here's the blog post on the subject.

By the way, it's nice of people to remember stuff I wrote. That's kinda cool, actually.

[Ironflight]

Originally Posted by Bob Collins

By the way, it's nice of people to remember stuff I wrote. That's kinda cool, actually.

What's that quote Bob...."They Like me, they really like me!!"

You do a great job of represnting and documenting the trials of the average builder Bob, and that is pretty important in my book. Keep it up! (One of thse days, you'll fly and become a hardened former builder/pilot that forgets to share....)

[SMO]

Here is how I did my big wire connections as per Bob Knuckolls. Worked good and they will never pull out, that is for sure:

http://www.aeroelectric.com/articles/big_term.pdf