Community Forums

lanthony2020 · 05-11-2015, 05:35 PM

Hello, I was reading an article on "Good Sam" about maintaining the electrical "Chassis Grounds" on RVs? With all of the issues surrounding an RV, this has to be a good practice?

I have a 2003 Safari Trek 3011 Motorhome, new to me, on an F53 Ford Chassis. My research has revealed a Bodybuilder's "Ground" just behind the gas tank, apparently for the Coach Builder, in this case, Safari (Monaco).

Does anyone out there know the number and location of additional "Grounds" for the F53 chassis? Any Safari Trek Ford folks know of any additional "Grounds" that Safari used?

Thank you in advance,

LN

MT4Runner · 05-12-2015, 08:56 AM

It's worth some time on a creeper underneath your RV to find that ground and follow it.

Does that chassis/bodybuilders' ground tie into the ground at your converter/distribution box?

How is the ground path from the coach batteries to the distribution box?

How is the ground path from the alternator/engine block to the coach batteries?

(The hot path should go through the solenoid when the engine is running so your alternator can charge your coach batteries. The ground path does not need to be switched).

On my '92 Four Winds, the ground path was from the alternator to the engine (good), from the engine block to the frame (good), from the frame to the body (bad), from the body to the bodybuilders' ground in the floor of the rv (bad), from there to the batteries (bad) and to the converter (good). A single bad point in that path means you will either not get adequate charging or you can't adequately use your coach batteries.

I sincerely hope that your 11-year newer MH will be better than mine...but it's worth checking. Don't take another Safari Trek's owner's word for it...if you're physically capable, find out for yourself. A different employee could have run the grounds on your coach than on another.

nothermark · 05-12-2015, 09:16 AM

I think what you are talking about is a tapped hole in the frame with a lug on it to accept a ground wire from the coach. That is what I found on our 2011 E-450 chassis. In essence the whole frame is a ground path so in theory you can tap a hole anywhere as far as electrical is concerned. What Ford does is put in a point so the house builders have a known connection point instead of drilling random holes in the frame.

TeJay · 05-12-2015, 10:01 AM

FYI, The ground aspect of electrical circuits were always necessary in the past but have gained even more importance with the advent of the computer controlled vehicles along with all the bells and whistles that have been added.

Here's just one example of how things have changed. Your lights and radio along with most systems use 12 volts as their source voltage. If that source voltage is off by a few volts it won't matter to much. When you get into computer circuits that's not good enough.

The TPS (throttle position sensor) does not use 12 volts but 5-volts. It needs a more precise, always maintainable voltage because the position of the TPS tells the CPU (by means of a variable voltage) exactly how you want to drive. The voltage coming from that sensor must be precise if fuel is going to be controlled precisely. The ground circuits play an integral role in keeping all voltage levels constant.

Most any good schematic circuits will have the locations and number of grounds marked and located for you.

MT4Runner · 05-12-2015, 02:48 PM

Quote:

Originally Posted by nothermark

I think what you are talking about is a tapped hole in the frame with a lug on it to accept a ground wire from the coach. That is what I found on our 2011 E-450 chassis. In essence the whole frame is a ground path so in theory you can tap a hole anywhere as far as electrical is concerned. What Ford does is put in a point so the house builders have a known connection point instead of drilling random holes in the frame.

Yes....in theory, that is correct.

....but add in road salt, rain, metal, and electricity together and you get electrolysis.

If you want to have less risk of long term frame damage or poor grounds, tie everything together with actual electrical cable and don't leave it to bare (or potentially bare) structural components.

lanthony2020 · 05-12-2015, 03:11 PM

Thank you to all that replied. I am disabled right now after 3 surgeries. I hate it. So I have to be anal and do my research so I can pass it along to a mechanic or friends that might be helping. I would be all over this thing and enjoying ever moment of it if able.

I think all comments were very valuable. I am taking it into the Dealership tomorrow to change out fluid/filters on tranny. They want to flush and said Ford recommends this. I don't like flushing. Thought I would side bar this in.

Since the motorhome is new to me, I am having Ford hook up to the PCM and check for updates and any tunes that may have been installed prior. (Trying to install 5 Star but fails) Another tune will cause this and or bad ground.

I think now, a good idea to service grounds anyway. Ford will do he "Ford" grounds, so be covered here.

Thanks,

LN

MT4Runner · 05-12-2015, 03:59 PM

Good luck.
You don't live anywhere near western Montana, do you? I'd take a look in exchange for coffee or beer.

lanthony2020 · 05-12-2015, 04:15 PM

I am actually thinking of Trekking up that way to South Dakota. I would probably catch the area around Yellowstone and then up and over through the Black Hills.

Hey thanks! What an offer!

LN

nothermark · 05-12-2015, 04:34 PM

Quote:

Originally Posted by MT4Runner

Yes....in theory, that is correct.

....but add in road salt, rain, metal, and electricity together and you get electrolysis.

If you want to have less risk of long term frame damage or poor grounds, tie everything together with actual electrical cable and don't leave it to bare (or potentially bare) structural components.

I am very familiar with electrolysis and ground problems. It can be a big issue with riveted or bolted parts but I thought those frames were welded. If so then not so big an issue. Guess I will take a look the next time I am under there. Still can be a problem getting the antenna's connected though. ;-)

FWIW Good grounds is also why I do not recommend putting disconnects in ground side battery terminals. If it is working why break a very sensitive system.