Dash wiring and grounds

[TulsaFred]

While inspecting the jumbled mess of wires behind my dash in preparation for a new harness, I see several apparent black ground wires. These are attached using ring terminals to a few of the posts securing the various gauges to their respective brackets.
I assume then that a good ground connection is important not only at the gauge bracket post, but also the bracket to dash interface. That interface looks tenuous as there is nothing to strongly secure the gauge bracket to the dash. It is just the posts on the back exerting some pressure on the metal bracket to keep it (hopefully) firmly against the backside of the metal dash.

Do I have it right?
If so, have any members had problems keeping good grounding?

I wonder if someone kludged my dash. Seems like a dedicated ground post makes more sense. The wiring diagram just indicates a ground, but not a location for that ground.

Thanks for any advice
Fred

 

[JPSmit]

Do I have it right?
If so, have any members had problems keeping good grounding?

Thanks for any advice
Fred

EVERY member on this board has had problems keeping good groundings (That is where the "British" on British Car Forum comes from)

seriously, probably not bodged, but anything you can do to improve will pay off later. BTW might not be that the wire is grounded to the instrument, but that the instrument is grounded through the wire.

 

[TulsaFred]

Thanks John-Peter,

The ground wires I'm referring to are not related to the instrument whose bracket is used to ground the wire.
These ground wires emerge from the wiring harness and appear to just "borrow" a convenient post to use.
For example, the speedometer has two ground wires attached to the passenger side post that secures it to the bracket/dash. Same for the Tach. They are not wires from those instruments, just coming out of the harness and attaching.

Also, there are knurled thumb wheel type nuts on these posts, but several are missing. Are these knurled nuts available anywhere?

BTW, it's a 59 Bugeye.

Thanks!
Fred

 

[jlaird]

Available from old cars. Sigh.

That is why we never throw anything away when parting out a car.

 

[The_architect]

Tulsa Fred,

I just did this on a 60 Bugeye last year, and I know exactly what you are talking about.

Um, yes, it is difficult to keep things grounded. Poor grounds are the bane of <span style="font-style: italic">all</span> Spridgets. I would say, in fact, that you cannot have enough ground wires. Keep 'em clean, bright, and tight.

All of your gauge's lights need to be grounded to work, and the fuel gauge itself in particular needs to be grounded or it won't work at all. As you have no doubt have observed there is only one wire going to the back of each of the gauge light bulbholders, and so yes, the metal shell of the sockets grounds it to the metal gauge case.

The idea originally was that the metal brackets would ground the gauge cases through metal dash, which in turn would be grounded to the car's body through the screws that hold it on. After 60 years of paint and rust it might not work at all, if it does I would be surprised if the lights are as bright as they should be.

The replacement harnesses for the Bugeye do not have a ground wire for each instrument, as the originals did not. So, when I rewired I too grounded all of the gauges together with short little ground wires with ring terminals on each end, that hopped from one to the next. I ran the last one to a ground that screws directly to the car's body. Did I say yet you cannot have enough good grounds?

Also, if I remember correctly I also had to solder a dedicated ground wire to the flasher bulb socket too. I highly recommend you use LEDs in these sockets, by the way.

Those gauge nuts have a special thread, but you can find them on ebay:
Dash nuts on Ebay.

When you get that replacement harness (I like these guys British Wiring) do observe that there are separate ground circuits within the harness and that these each have their own point where they have to be screwed to the body. The ground wires do not terminate at a single main ground.

Once you get your harness, it is extremely helpful to match each color against your BE wiring diagram. I made a little label for each wire.

I also pulled the dash and wired all the switches and gauges on the bench, then I put the dash, gauges, wires, switches back in as a unit. It is a perfect time to recover the dash with vinyl if it needs it.

You may find that there are chalk marks on the back of your dash that were put there when your car was assembled at the factory

Good luck,
Charlie

 

[TulsaFred]

Thanks Charlie,

Very helpful information.
I've already ordered those dash nuts form ebay.

I think I'll follow your lead and string a ground wire hopping along the gauges and then to the body.

I've wire wheeled the backs of my gauges to remove scale and rust and then painted them with black epoxy paint. No doubt this will add to grounding issues.

Looks like dash components are not repro'd much. The brackets, nuts, temp sending tube, oil pressure sending tube, etc. all not available thru Moss, VB, or AH Spares.

Best
Fred

 

[jlaird]

Wow, those guys got parts.

 

[Jim_Gruber]

And very expensive parts.

 

[jlaird]

Price is only relative. How bad do you need it. LOL

 

[The_architect]

Hi again, Tulsa Fred

I think if your gauges' studs are clean and not epoxied with paint, you will have no problems with grounding them, with the loop-to-loop ground wires. No problem at all.

You realize that the temperature gauge/OP gauge is the same gauge? The temperature gauge has a skinny tube wrapped around a heavy gauge wire. The engine-side end screws either into the block behind the genny or into the radiator. That tube is not replaceable. It is integral to the gauge. The oil pressure portion of the gauge has a 1/8" diameter pipe screwing into the backside of the gauge the other end screws into the block right behind the distributor. If this is pipe is missing it is probably capped at the block.

I bought my combination temperature/oil pressure gauge from The Gauge Shop in the UK. Straight up guys, answered all my questions promptly and I had my gauge in about three weeks. If you buy it from them there is no need to send a core. Several eBay vendors sell them. I guess they are around $150.

If you need replacements or rebuilding on your original Bugeye speedos, tachs or fuel gauges, AH Spares can do that for you. You might have to send your old gauges as cores to AH Spares though. I sent my speedo and they exchanged it for a new one; they had my fuel gauge rebuilt for me.

I had my BE tach refitted with an electric tach by a vendor here in the States (long story) and that is one way to skin that cat.

Good luck, you'll make it! Compared to some other things other people have done this is a drive in the park.

Charlie

 

[TulsaFred]

thanks for the info guys

I do have the combination gauge and it was working before I took the dash apart, but it has a plastic tube for the oil pressure. I wanted a copper tube for the oil pressure and needed a bracket for the speedo and a few missing knurled nuts. I was surprised that none of this was available at the major vendors.

I did order 4 knurled nuts for a few dollars from the ebay salvage yard guys.

I also read that you can simply buy 1/8" copper tubing from a local auto parts store and some 1/8" NPT fittings (which apparently work fine despite original "BSP" threads, perhaps with a little teflon tape). I was directed to Mcmaster.com for the fittings by another thread.
Why wouldn't Moss/VB just offer this in their catalog? odd.

I didn't realize the temp sending tube/wire was integral to the gauge. Mine screws into the top right side of my radiator. I'll have to be careful with this. Curious: how does temp wire/tube function to transmit the temp?

Best
Fred

 

[The_architect]

HI Fred
I have read that the capillary tube is filled with ether. When it expands it moves the needle. Be very careful with it.

I also found it bizarre that the usual suspects don't carry the oil line. I think Spridget Mania has a braided hose that may work. Or there is this company in the UK if you are not in a hurry: Speedograph Richfield. I ordered mine from small parts supplier in the UK over eBay, but I don't see his offerings on there anymore.

That same company that has the gauge nuts probably has brackets too. Give em a call.

Good luck
Charlie

 

[jlaird]

Well shucks, I am haveing a senior moment. There is a source and it is in OZ. Nice guy, good stuff, reasonable prices. I even have one from him. NO markings, he has em made.

Someone help me out here pls.

 

[TulsaFred]

Hmm
would definitely be nice to just order the tube with the correct fittings
rather than try to piece together, only to find out you made a mistake when it arrives.

Fred

 

[jlaird]

https://www.spriteparts.com.au/ Here ya go, brain finaly chunked.

Colin Dodds, nice guy, send him an email and mention my name if you wish. We know each other.

Just describe what you want and he will get back to you with all the imfo.

The man is a wizard with BEs and Spridgets. check his site carefully.

 

[The_architect]

Say, Fred, I got mine from this guy in the UK, Chic Doig. Chic Doig's eBay page. He doesn't have it listed right now but you could shoot him an email if Jack's supplier doesn't work out.

Best
Charlie

 

[middie]

----------------------------------------------
<span style="font-style: italic">https://www.spriteparts.com.au/ Here ya go, brain finaly chunked.

Colin Dodds, nice guy, send him an email and mention my name if you wish. We know each other.</span>
------------------------------------------------

Exactly right, Colin is a terrific bloke, and I'm lucky enough to live only an hours drive from his place.

Good shoulder to have a cry on as well - very helpful. You could mention Wazza as well, but he may temporarily lose control of his emotions

Wazza

 

[TulsaFred]

Thanks for the tips guys,

I ended up finding a kit at autozone that seems like it will work:
part number CP7584 for $10.99.

I've added the recommended suppliers to my contact list, though.

Went ahead and took the wire cutters to the wiring harness today and pulled the dash all the way out.
There was yellow handwritten notation still on the back with the car's serial number, as well as options/fitment ("MPH" "R/C" "W/W" for mph speedo, rev counter, and windshield washer).

Onward with the resto!

Fred