BMW engine ground strap. Any old thing to replace?

[Bob Kontak]

2008-ish 325xi (ix?). Customer says cranking slowly. I say ground strap as I have seen identical on the BMW jeeps.

Three weeks, seven appointments cancelled to confirm problem. Finally breaks down 30 miles away and has to have it towed here.

Anyhoo. Broken ground strap. I ripped it in half with a tug. Almost the diameter of a 410 shell. Do I replace with factory part or is anything fairly robust good enough?

Pic is LF wheel well, rearward.

[304065]

Why not use the factory part? If you use something else and have problems in the future, you will always have doubt. And remember that if you have 100 amps flowing in the wires, you need 100 amps flowing in the ground.

[Bob Kontak]

Originally Posted by 304065

And remember that if you have 100 amps flowing in the wires, you need 100 amps flowing in the ground.

I hear you. I'll call BMW in the morning. "Last eight digits of the VIN, please"

Just bet you they have it in stock. Why? Reasons.

Guessing $82 just on a wild a*s guess. Will report back.

[sc_rufctr]

I've never liked those braided ground straps. There must be a reason so many manufactures use them (flexing/movement?)
but I'd make something like this. Except I wouldn't use red heat shrink on a ground strap.

[GWN7]

The braided straps on the 914's corrode internally. Someone measured the resistance and found it to be 60-70%. Replace it with the coated aftermarket part unless this is a trailer queen. I used to add a ground strap from the battery directly to the engine/trans. Solved most starting issues.

[Bob Kontak]

Originally Posted by GWN7

The braided straps on the 914's corrode internally. Someone measured the resistance and found it to be 60-70%. Replace it with the coated aftermarket part unless this is a trailer queen. I used to add a ground strap from the battery directly to the engine/trans. Solved most starting issues.

Did this. It was a horribly tight fit and a nasty job.

Still no start. Tried all the tricky things per the internet like disabling the intelligent battery system. Then I finally find the starter. OMG. It's under the intake runners and the trigger wire is inside a sealed connector. Just kill me.

However. It took less than 30 minutes to gain access and confirm starter was dead. Not bad. Starter stunk bad like burnt electrics. Ground strap surely caused or hastened it's death.

Thanks all for the input.

[sugarwood]

Originally Posted by Bob Kontak

Guessing $82 just on a wild a*s guess. Will report back.

For the record, it's $20
12427551714

[Bob Kontak]

Originally Posted by sugarwood

For the record, it's $20
12427551714

Thank you. I did not ask as I went with the $5 coated steel cable. Original only lasted ten years.

I spent $15 on the aluminum stretch bolts for the starter but got a free cup of Starbucks at the BMW dealer. They had an I8 there I scoped out.

Then $35 on Mahle intake to head gaskets (O-rings) from Advance Auto.

Did you find that online?

[john70t]

Water and cancer gets in the end and wicks it's way through the cable eventually.

You can put anti-corrosive with lubricant such as petroleum jelly and seal it up with shrink tube and Liquid Tape(may not hold up to severe heat).
I don't know if the jelly affects the factory wire wrap, but remember it is only a ground like the chassis and everything else exposed.
There is no rule except concours dictating you can only have one single engine ground.

[Bob Kontak]

Originally Posted by john70t

Water and cancer gets in the end and wicks it's way through the cable eventually.

Where the strap is located and being in Ohio I can't argue.

However, this is not normal for every day cars. (BMW symptoms) I see Jeep/Chrysler copper/brass ribbon ground straps that have zero integrity but the car still starts.