Electrical ring connector failure

[Mark Maulden]

Waiting out some rain here in the Broughtons and thought I'd pass this along. Several days ago. I noticed the alternator was not charging. Hit the dock at Pt. Harvey and started investigating. Alternator is a Balmar series 6 80a with a 614 regulator. Turns out the regulator was not getting battery power. Fuse was good so started following the wire. I had crimped the end to an anchor ring connector and put it on the alternator output about a yr ago. When i touched it, it just broke between the crimp and the ring. Seems it did not like that environment as the metal looked pretty stressed and this engine does not shake much. Wiring was all loomed and zip tied etc. Replaced the ring and will fix it this winter when i combine my 4 GC2's and install an echocharge. The "old guys" on the dock suggested I tap the regultor with a hammer. That's what they did back in the day with their cars......So, I guess the moral of the story is keep smaller electrical connections off the engine.

 

[Stu Jackson]

Hi, Mark, great weather we're having. I'm in Cowichan Bay, 21C.

Good point about ring terminals on alternators. ALL, every single one, of the factory crimps on the regulator wires separated at one time or another on my boat. I blamed them. Then, of course, the few I did myself also died!!!

You're quite right.

Enjoy, nice to hear from you.

 

[agprice22]

A picture of the connector and wire would be wonderful. I would like to see what failed and how. What guage wire? Was it shrinked and adhesive sealed? Was there strain relief? Do you think it became brittle with heat/cool cycles?

 

[Stu Jackson]

I would like to see what failed and how. What guage wire? Was it shrinked and adhesive sealed? Was there strain relief? Do you think it became brittle with heat/cool cycles?

Andrew,

Actually, in my case, as I explained: ALL of the above.

Ya really don't need a picture.

The only two that haven't failed on me are the #2 AO (alternator output) and ground.

 

[Mark Maulden]

Sorry no pix. It basically fell apart when i touched it and I just needed to get it fixed. I think it is 12 ga wire as it has to supply field current. It was an Anchor adhesive lined heat shrink ring connector. Any crimp connector I use is such. There was strain relief as it was tied into other wiring that crosses the engine. There was also a drip loop at the alternator so no tension stress. I like drip loops. As far as heating and cooling, I dont think that was an issue. There is a lot of area to spread some heat around and I dont let the batts get low enough for contact heat to get high to spread from the ring to the crimp. My thought is it's a vibration environment even though the engine doesn't shake. But there are still high frequency components to vibration...

 

[Mark Maulden]

The only other small wires on the engine is the temp sense and oil pressure sense. But they dont get the belt vibration and rotating magnetics vibration....I learned a lesson here..

 

[centerline]

im not going to preach about using the expensive marine quality heat shink terminals (not all of us do all the time) but at the very least it is a good practice keep a length of adhesive heat shrink tubing to use on the terminals that attach to the motor, as the heat shrink allows a good strain relief and minimizes the connection failures due to corrosion and broken wires at the crimp.

 

[agprice22]

I see. Thanks. Spares. I will stay away from those connectors . The ones I am using come with the adhesive shrink. I have a BSP kit. The torch is a little dinky, but it gets it done.
Thanks!

 

[Ron20324]

I think some people are not reading the OP: " broke between the crimp and the ring" tells me that this is not an area that shrink stuff will do any good.

 

[centerline]

I think some people are not reading the OP: " broke between the crimp and the ring" tells me that this is not an area that shrink stuff will do any good.

I read the post and thought i understood what he meant...so if the wire is breaking as it comes out of the crimp, the shrink tube would help support it... but even if its breaking farther back, a longer piece of the shrink tube would help support it... the key is to use the adhesive stuff.

if the wire is supported well enough and the viberation is extreme, the terminal eye will fail as it fatigues and breaks at the stud.. and this cannot be helped by shrink tubeing.

 

[Mark Maulden]

Ron is right and centerline is right..But the crimp was still on the wire and THEN dangling when i touched it. And, it was still a good crimp that was also heat shrunk...the ring was still on the alternator stud. When it happened, I was at first, at a loss as to where the wire terminated. It was not obvious..It had to be the stud so I took the nut off and there was the ring..hopefully, this clarifies.

 

[agprice22]

Yeah. I see it now. I was picturing the crimp failing. The terminal broke between the crimp and the ring. The crimp would seem the most obvious weak point, but it is supported by the shrink. The ring is beneath a screw or bolt, but the thin tongue between them would bear the brunt of force from vibration. A good harness, as was mentioned before, would reduce it, but they would eventually suffer. Good idea to give them a physical inspection now and then. I am sure there is never a convenient time to lose a connection.

 

[Capt jgw]

Try running the wire through a wire clamp or zip tie attached to the alternator before the terminal. That way the alt and wire will vibrate as a unit and the ring won't fatigue. The bending will be spread out over a few inches of wire instead of concentrated at one point.