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Discussion Starter #1
Hello, could anybody be so kind as to tell me where I find the earthing points in a 1978 Silver Shadow 2 / T2. I have a lot of motors running slow, seats, wiper, windows etc. and I would have thought its the easiest place to start looking. Thanks very much in advance.
 

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Start with the fuse panel and carefully remove each fuse, one at a time and clean the end caps with a scuff pad or 0000 steel wool.
The wiring diagrams and basic electrical section of the workshop manual shows where fuses and relays are located. Some of the major ground are also described.
Battery terminals must be clean and the ground cable next to it.
 
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Also, thoroughly check the engine to chassis earth cable. This is situated at the rear of the engine, I think from a bell housing bolt to chassis.

Jake.
 

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Discussion Starter #4
Hi, OK I will check that, but I am guessing there is more than 1 earth cable?
 

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Start with the fuse panel and carefully remove each fuse, one at a time and clean the end caps with a scuff pad or 0000 steel wool.
The wiring diagrams and basic electrical section of the workshop manual shows where fuses and relays are located. Some of the major ground are also described.
Battery terminals must be clean and the ground cable next to it.
I think I know the location of all the fuses, its just the earthing I want to check. I will clean all the fuses as suggested, would it help to put a vert thin coating of WD40 on them? Thanks
 

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I only have one engine to chassis earth strap on my Shadow 11 which is a RH drive and the strap is near to the starter motor. Another Shadow 11 I have seen lately, only had one engine earth strap also.
When I restored the car, this earth strap was not connected at all. Everything worked but slow including cranking the engine. Once rectified, no problems.

Very common for windows and seats to be very slow in operating. As windows go, a through clean of motors and there mechanism will usually sort them out. Check windows are free in the channels they run in. Using dry silicone spray in the channels can help as well. They will never operate at the speed of modern cars.

Jake.
 

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Discussion Starter #7
I only have one engine to chassis earth strap on my Shadow 11 which is a RH drive and the strap is near to the starter motor. Another Shadow 11 I have seen lately, only had one engine earth strap also.
When I restored the car, this earth strap was not connected at all. Everything worked but slow including cranking the engine. Once rectified, no problems.

Very common for windows and seats to be very slow in operating. As windows go, a through clean of motors and there mechanism will usually sort them out. Check windows are free in the channels they run in. Using dry silicone spray in the channels can help as well. They will never operate at the speed of modern cars.

Jake.
Thanks very much, yes i used the silicone spray but it didn't have much effect, I was hoping it was the earth. I also thought various parts had different earths, but I will certainly check the one near the starter motor. I have seen the videos with the modification using the central locking or cigar lighters to power the windows and they fly up an down, but it is well beyond my capability to do that. Thanks again
 

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There are quite a few separate earthing points on the car for sure. Far to difficult for me to list them all. I am not sure if they are listed in the workshop manual, they probably are.
Someone else might post the various locations for them.

I would definitely not go down the route of adding more wiring and using a heavier wire to get them to work faster. IMHO that is just a way of getting them to work a bit faster and not really solving the problem of taking them out and cleaning them, doing the job properly.

I do not know if the car has been standing for quite a period but many things will get better the more it is used. I, especially during the summer, open all windows when I leave the car overnight and then close them upon driving. This keeps them all working very well.

Jake.
 

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Discussion Starter #9
Thanks, it is in everyday use but that said everyday is perhaps only 3 times a week during lockdown. I get your point about the wiring. I was hoping that someone would've a list of earthing points that I could check over. Lets hope they do. Thanks again
 

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There should also be an engine earth strap from rear of the B-bank valve/rocker cover to the front bulk head near the LHS bonnet catch.
 

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Discussion Starter #11
Hi Great I will have a look at it. Are there any others that you know of?
 

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The front subframe is totally isolated from the body, so therefore it has a few ground link straps to the body. Usually 2 on top rear from valve cover to firewall and two from the rear motor mounts to body. There are other ground hubs but will not help your issue.
Slow windows. I have dealt with this issue on many cars and the latest project had a slow window when going upward. The windows generally move quicker when going down due to gravity. I found the window channel material to be the issue on my latest build. How did I know? Un-fastened the window from the motor carriage and manually moved it up and down and noticed the binding. Sometimes the window frames are out of alignment and bind the glass.
 
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There are lots and lots of earthing points on these cars.

As to windows and slowness, I can stand behind the modifications specified in the Window Lift Improvement Article by Richard Treacy. Cleaning up the motors certainly doesn't hurt, either.

The wiring to these motors is clearly "insufficient" if you compare it to what was used on other cars of the day and later on across makes and models. Crewe was in a horrible budget squeeze for quite a while, and cost cutting measures were undertaken. The wiring for the window motors would have been far more "robust" otherwise. My 1989 DeVille, now sold to a friend, looked like it had transatlantic undersea wire for the windows, all the way from the switches to the motors, compared to what's in my Silver Shadow II and Silver Wraith II.
 
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Discussion Starter #14
The front subframe is totally isolated from the body, so therefore it has a few ground link straps to the body. Usually 2 on top rear from valve cover to firewall and two from the rear motor mounts to body. There are other ground hubs but will not help your issue.
Slow windows. I have dealt with this issue on many cars and the latest project had a slow window when going upward. The windows generally move quicker when going down due to gravity. I found the window channel material to be the issue on my latest build. How did I know? Un-fastened the window from the motor carriage and manually moved it up and down and noticed the binding. Sometimes the window frames are out of alignment and bind the glass.
Great thanks very much, do you know where the earth for the windows is located as I might as well tidy it up anyway.

Thanks
 
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