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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - replacement wiper motor wire

I'm in the middle of replacing the wire for the wiper motor on my TD. The new wire I got from Abingdon Spares is rather strange: inside the gray outer cable are two VERY SMALL red and yellow wires with maybe one strand of copper wire inside each and a LOT of thin copper strands that aren't inside anything, as if they are to be used as a ground or something. Is this correct? It looks to me like a manufacturing defect but I certainly not an expert on this kind of thing.

The old cable has red and black wires inside which look to be about 18 gauge each. This is definitely not the case with the new wire.

I was about ready to solder the new wire to the old in order to pull it through the windishield frame and discovered this.

Abingdon is closed on weekends so I can't call them. Any advice would be greatly appreciated!

Bryan
52 TD Mk II
B Sieling

Brian - The replacement cable sound like twinax or twisted, shielded pair. I have found that the original wire was barely adequate to handle the current for the wiper motor without (what I felt was) excessive voltage drop, so i'm not sure that the new wire will handle the current. Perhaps Bob Jeffers will weigh in on this subject since he rewinds the motors and has a better feel for the situation. Good luck - Dave
David DuBois

The the best way I suggest of using that sort of cable is to use the sheathing "as you say lot of thin metal strands" as the earth return for the wipers and then join all the other conductors to form the live (making sure they so not come into contact with the outer shearthing. this will give you a good live and return paths without too much voltage drop. Moss also sell a similar cable as the wiper cable.

Even so - dont rely on the wipers !!
J T Smith

My wiper motor ran at a useless craw when powered by the two wire, small gauge which was necessary to fit inside the chrome windshield frame. And the motor would get hot in short order.
I replaced the two wire arrangement with one wire of heavier gauge, running it's original route (through the chrome frame) to a negative battery supply. Running a second short wire from the motor the chrome frame attaching it to one of the mounting bolts for the wiper motor.
I still run the electrical system OEM, as a positive ground.
The motor now runs up to a decent speed and doesn't get hot.
Just my two cents worth.
L. B. Tyson

Bryan; I have used the one wire method for over 20 years without any problems at all. Just ground the windshield frame and run one short wire from the mounting post to one side of the wiper motor.
Sandy Sanders
Sandy Sanders

My motor definitely runs very slow but I don't know if it gets hot or not. Never thought to touch it and I never really run it long enough to get hot anyway.

If I do the single wire method, I would want to pull the wires out of the new Abingdon wire and use the gray outer covering because of the wire's visibility between the windshield frame and the cowl.

I assume I would run the new, heavier (16 gauge?) hot wire to the same A4 terminal on the fuse box as per the original.

How does one "ground the windshield frame"? Is it not already grounded by virtue of being bolted to the sheet metal of the body or is there something else needed to insure good ground?

If I were to use the "twinax" or "twisted, shielded pair" replacement wire, how does one make connections with such thin stuff?

This all started because I wanted to replace the rubber weatherstrip along the bottom of the windshield frame and thought while I had the windshield on the bench I would replace the wiper wire at the same time. The wire was looking pretty bad and had been cut and spliced in a couple places under the firewall.

Its been either hot or rainy in DC lately, which makes it a good time to tinker on something in the cool basement!

Bryan
B Sieling

Haven't seen the replacement wire sold by 'the' companies, but saw the exact same outer sheath at a local hardware store...was thermostat wire and really thin inside wires (plus ground)...looked way too thin, but the sheath looked right. Would think the suggestion of using the outer wire for one lead and combining the two inside ones for the other would work...have heard of it done.
As for the original, my wipers just finished about 5 hours of wiping...worked well, and I thought fast. The motor heats up very hot, but seems to level out and just stay hot.
I have never had the 'grease' end open, just the motor end, but I added a little 'oil' as in three-in-one through the little 'drip' hole figuring it might loosen up any old stuff in there. Something must have worked as they were great (ok, so i'm the only one who likes them and hates Rain-X)
gordon lawson - TD 27667

Bryan,
Using a test light, one of those that look like an ice pick with a bulb in the handle with a long wire with an alligator clip attached.

Attach the alligator clip to a battery terminal and touch the point end to the windshield frame. If the bulb doesn't light switch the alligator clip to the other battery post and recheck, the bulb should light.

By the bulb lighting proves you have completed a circuit. By connecting a short wire from the wiper motor terminal to that frame or a screw attached to the frame, And the other terminal to a wire fished through the frame itself, out the bottom into the hole of the body and connected to the wiring under the dash you should be in business.

One wire from a lamp cord will do the trick, place some black heat tubing over the section exposed at the windsheield frame to the body. Heat tubing can be purchased at Radio Shack.

As a final note, I always solder all wire connections, ever those squeeze terminals. I want a positive connection.

Hope this helps.
Lee
L. B. Tyson

Looks like I've got some options here. I did just get off the phone with Bob at Abingdon Spares and he told me the bare copper strands inside the replacement cable are just a shield and should be cut off. He assures me the two really small gauge wires will carry the current and will work fine but admitted it is difficult to strip their outer coatings without cutting through the wire inside. He did suggest to put a little solder on the ends of the wires so the grub screws have something a little more substantial to clamp on to.

Thanks for all the advice and suggestions. I will play around with this and let you know what I end up with.

Bryan

B Sieling

Anyone pulled the inner wires out and put heavier ones inside....or is this possible? (the outer covering is such a nice period match).
gordon lawson - TD 27667

I was thinking of giving that a try, but its tight and pretty well formed together. Might be possible to pull the wires out of a short section (just the part that shows between windshield frame and body?) but a long section could be difficult.
B Sieling

Bryan, one more option, if it hasn't been mentioned , is to twist the two small gauge wires together at each end of the flat wire, and use them for the voltage feed to the motor. The add a ground wire as others have suggested. The two wires together should carry the load with no drop.
I remember the routing of the flat wire bundle was very tight through the windshield frame and I don't think you would have much success pulling the old out and new in.
FWIW
Dallas
Dallas Congleton

Before messing around with the shielded wire I'd check with Rhode Island Wiring Service. I took a trip down thre one day to check them out and was very impressed. They're at www.riwire.com, 800-241-1955 or 401-789-1955. The head engineer is restoring an MGB.
Bud Krueger

Back in the 70's I found a roll of 'European Phone Cord' that was an exact match of the wire, sheath color, dimensions and black/red wires. If someone from the UK can be on the lookout perhaps its still offered?

Chris
Chris Couper

More great suggestions. I will definitely check out Rhode Island Wiring.
B Sieling

I went to NAPA today and found they had on their wiring carousel a package of the very wire we need. It is in 25' length and retains for $15.00. It is exactly like the wire purchased from Moss but the colors are red and black not white and black. It has the identical silver colored exterior.
Sandy Sanders
Sandy Sanders

Sandy, could you give us the NAPA part #, please?
Bud Krueger

I went to Home Depot this morning and to my utter amazement found wire that is looks to be a perfect match: red and black multi-strand copper wires inside a smooth gray outer sheath. It is called "Sound and Security" wire and is available in 16 and 14 gauge. The 14 gauge is the exact same O.D. as the original wiper wire. The 16 gauge is slightly smaller O.D. but still heavier gauge than the original and would be easier to fit through the windshield frame. Any reason why this stuff wouldn't work?

Bryan
B Sieling

Either should work perfectly, unless of course the wire isn't available with 'lucas smoke' already installed. (sorry about that last bit, I just read a friend's MGB Driver which had a very humorous article by Craig Bolton on the subject of Lucus Smoke)

Thanks for the tip on the wire. I'll probably run down to HD and pick some up as well.

warmly,
dave
Dave Braun

It is kind of a smokey gray color...

Maybe this is the same/similar stuff that Sandy saw at NAPA?
B Sieling

I stopped at Home Depot today and had a look at the wire. I'm not so sure that you'll want to use it. It's twisted within the outer sheath and is somewhat circular than than flat. I suspect that the spiral effect would be somewhat of a problem inside of the windscreen frame. Just MHO.
Bud Krueger

I thought if I went with the 16 gauge, which has a slightly smaller O.D. (but bigger gauge wires) than the original, I should have plenty of room inside the windshield frame. I've got the right side member of the frame off and the top member raised up a bit at the right end to make feeding it through the top member easier.

I did get an e-mail response from Rhode Island Wiring Service. I'm going to send them a sample of the original and they may be able to make something up to match (and hopefully add it to their catalog).

I've still got the wire from Abingdon with the really small gauge wires as a fall back.
B Sieling

When I rebuilt my windshield, I used plain old braided copper lamp cord. It was flat so it fit in the windshild frame very nicely. I only used the silver/gray tubing for the part between the outside of the frame through the hole in the cowl. The wiper motor works fine and the change in type of wire is not obvious.
Jim Merz

NAPA wiper motor wire.. The NAPA number is 785750 and is 16 GA. It is grey and appears to be the same as Moss wire.
Sandy Sanders
Sandy Sanders

I finished the wire installation this afternoon. I ended up using the 16 ga "Sound and Security" wire from Home Depot. It fit fine inside the windshield frame and the exposed section between the frame and cowl looks good. There was some printing on the wire. I couldn't find any solvent to remove it but was able to position it with no printing on the exposed section. The best part, however, is that the wiper motor runs faster now. Still slow by today's standards but noticeably faster than before. Had I had time I would have checked out the NAPA wire Sandy found but I needed to get the car back together for an event this weekend. Thanks to all for your input.!

Bryan
B Sieling

I am reactivating this to Provide the following information.
I am installing the WW Motor wiring. I am using new wire from Moss (I think, but it could be Abingdon) I am using the bundled up ground wires as the ground lead. I have tied the red and yellow together for the hot lead.
Powering up the motor with a battery charger, and using a very accurate analog Ammeter, I find the motor draws between 1.8 and 2.2 amps depending on where you are on the large gear. (The motor was disassembled and refurbished. It is lubed with a Teflon based white grease. It has a new shaft. the wipers blades are fresh(?). They are 25 years old but have never been opened. The arms are new from Abingdon.)

Under these conditions the voltage drop in the bundeled shield wires is in the range of 0.1V. (Measured with Beckman digital volt meter,) The voltage drop in the two paralleled wires (Red and Yellow) is 0.2 V. The meter has only a resolution of 0.1V.

I dont think that amount of drop warrants changing out the wire.

Jim B.
JA Benjamin

Jim, I used the same wire (A/S) in 'the53'. Works fine.
Bud
Bud Krueger

This thread was discussed between 24/06/2006 and 09/02/2014

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