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I just never understood that MB would not have a direct ground cable to the engine block. Grounding to a single fender can't be good for long term.
With that in mind, I found a wide open area at the bell housing. I wanted to use the bolt lower that didn't have a bracket, but it was too close to the exhaust pipe. So here is where I decided:
There are several ways to connect to battery but I choose the easiest. There is an empty stud on the batter terminal.
I decided to go with a #4 wire that is 40" long. The common part number is A40-4L.
To remove the bolt from the bell housing use an E14 socket.
Slide the terminal on and retighten.
After threading the cable around the RCM box, you can then connect to the battery using the appropriate nuts and washers.
I slid some loom on it just for additional protection.
I NO LONGER SUPPORT MY POST - after careful thought, I have made up my mind James' idea is the best way. Our cars were designed with a HEAVY ground to chassis due to the fact that we have a lot of high current loads (brake controller, convertible top pump, engine fan, etc.) that get a ground return thru the chassis. For this reason, my fix below is not adequate. I won't remove it, as I think it's an example of a BAD idea and if YOU have this idea, I'd suggest you consider doing James' fix instead. I never remove what I think are my bad ideas, I think it's better to be intellectually honest and leave them up. January, 2023
So when I got the SE, I wanted to 'fix' this before it became an issue.
Just for the record, THIS TIME, I did it James' way and not MY way.
Well---- a modified "James way". I bought a generic cable at Autozone, put a BIG lug on the
Have to share a before and after view if a ground strap (pretty stout) that appears to be factory. Hope others will chime in to confirm.
Notice the heavy green corrosion (think its 13 years worth). Took a wire brush to clean off the loose stuff then used a small paint brush and baking soda/water to clean those wire strands.
You guys might want to check that strap if you are not doing what Janes1549 suggests here.
Regards,
Last edited by CROSSFIRERUSH; 08-24-2018 at 07:36 PM.
Reason: Add a photo
There is likely as much under the crimp as on the cable itself. Cleaning the cable did nothing for you, the wires, under that corrosion, are handling the current fine.
But any corrosion between the wires and the crimp lug IS a problem as THAT corrosion is in the path of current flow.
As old as our cars are getting, it's time we all took a look at that jumper.
Yup. Either I'm going to remove it, soaking the crimped ends in baking soda/water or replacing the cable with a shorter version as James1549 used in his original post.
I looked under my 05 and it was there. Never noticed it before. Good to know. I still feel better with a cable directly to the engine from the battery. Thanks for posting the pics.
Your welcome! Glad to help. This SRT6 has spent its life sheltered but in a hostile, rust belt environment. Definitely worth the trouble to get under her and look for any deterioration.
Thanks again James1549 & Pizzaguy. Today I installed that 40" long ground cable directly to the battery and to the bellhousing. I still need to add that plastic sheathing to somewhat shield that cable from heat. I also replaced that shorter, bare copper ground on the bell housing to the frame structure. I bought a 12" length, it could have been 8" or 9". Pics follow. Cheers!
This 12" cable replaced the factory raw copper cable shown previously above. This ground strap is on the driver's side, bellhousing to frame structure.
Thanks again James1549 & Pizzaguy. Today I installed that 40" long ground cable directly to the battery and to the bellhousing. I still need to add that plastic sheathing to somewhat shield that cable from heat. I also replaced that shorter, bare copper ground on the bell housing to the frame structure. I bought a 12" length, it could have been 8" or 9". Pics follow. Cheers!
This 12" cable replaced the factory raw copper cable shown previously above. This ground strap is on the driver's side, bellhousing to frame structure.
Regards,
The cable could be just bare copper wire, there is no need to have plastic on the cable, it is not as though it would be dangerous if it touched the chassis. Adding plastic to protect plastic seems to be a waste of money, route the cable away from excess heat and the insulation should be fine. The replacement for the OEM ground wire should be long enough to make a loop in it if possible, too short and it risks getting work hardened and slowly fracture over time.
My fix for a ground cable to the engine
