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Frayed Wire at Overdrive

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Dave Richards

Dave Richards

Jedi Knight
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3000 BJ8, the gearbox cover is off and I'm cleaning and puttering...There are 2 wires at the overdive unit, one long one from the front of the car and one short one that starts and terminates right at the OD unit.

The long one has a cover and is in good shape. The shorter one has two big gouges with frayed wire bits poking out. The OD has operated flawlessly since I've driven the car.

I'm baffled about what could cause the fraying of this wire, since (I think) it's only the fiberglass cover that's near it. I'm going to replace the wire, of course, but I'd like to take steps to protect the new wire, any suggestions?
 
The short wire is from the gearbox 3-4 interlock switch to the solenoid, as you know. Fiberglass is quite tough & abrasive. It could easily wear the insulation if in contact with the wire. My car has a small wiring clip on one of the transmission housing bolts to keep it in close to the machinery. I guess you could either add a clip or put some armor sleeving over the offending wire.

Actually it sounds more like the wire got pinched in the wrong joint at some time.
D
 
Thanks Dave, I did notice the longer wire has a clip on it about 1/2 way down the gearbox.

It may have been pinched, but I can't fiqure out how...it's probably not important, now, I'll put some armour on it and figure out a way to clip it, I'll post a picture tonight, if I have time. I hadn't considered the abrasiveness of the tunnel.
 
Dar 100 if my mmory serves me right both wires should run in the protective tube and be held inplace by the metal clip. It is advisable to slip a bit of shrink tubing over the frayed one first.---Fwiw---Keoke

Nope! only one long wire. I rewired mine and ran a twisted pair down to the switch.
 
I looked at it closely tonight. The short wire is wired directly into the selonoid. I don't think I should be messing around in there, or should I??? /ubbthreads/images/graemlins/devilgrin.gif It was these two tiny (tempting) screws holding a plastic cover on the top of the selonoid. Take it apart?
 
Now you have me confused. The OD solenoid should have a rubber cover on the top. A wire goes through the cover to the electrical contacts inside. The other end of this short wire goes to the 3-4 interlock switch. The rubber cover is held on by a crimped metal band. If it is this pigtail wire that is damaged just put an insulating sleeve over it & secure the wire out of harm's way. Don't take the rubber cover off the solenoid. There is a delicate set of contacts in there that don't like to be disturbed, unless of course, they aren't working. I don't believe you have a problem with them at this time.

I don't know what the "two tiny tempting screws" are.
There are a couple of solenoid mounting screws lower down that mount the solenoid to the OD housing. Don't take these screws loose. If you do, it will likely require resetting the solenoid adjustment.

It should look like item 48 here:
https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=28884
D
 
[ QUOTE ]
I looked at it closely tonight. The short wire is wired directly into the selonoid. I don't think I should be messing around in there, or should I??? /ubbthreads/images/graemlins/devilgrin.gif It was these two tiny (tempting) screws holding a plastic cover on the top of the selonoid. Take it apart?

[/ QUOTE ]
/ubbthreads/images/graemlins/savewave.gif

/ubbthreads/images/graemlins/nonono.gif No you should not be messing around in there. /ubbthreads/images/graemlins/nonono.gif No do not take anything apart holding the cover on to the soleniod either. /ubbthreads/images/graemlins/nonod.gif /ubbthreads/images/graemlins/nonod.gif---Keoke /ubbthreads/images/graemlins/hammer.gif
 
[ QUOTE ]
Now you have me confused. The OD solenoid should have a rubber cover on the top. A wire goes through the cover to the electrical contacts inside. The other end of this short wire goes to the 3-4 interlock switch. The rubber cover is held on by a crimped metal band. If it is this pigtail wire that is damaged just put an insulating sleeve over it & secure the wire out of harm's way. Don't take the rubber cover off the solenoid. There is a delicate set of contacts in there that don't like to be disturbed, unless of course, they aren't working. I don't believe you have a problem with them at this time.

I don't know what the "two tiny tempting screws" are.
There are a couple of solenoid mounting screws lower down that mount the solenoid to the OD housing. Don't take these screws loose. If you do, it will likely require resetting the solenoid adjustment.

It should look like item 48 here:
https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=28884
D

[/ QUOTE ]


That's the one, HOWEVER, there was no crimped metal band around the dust cover, it slid right up and that's where I discovered the two tiny screws, I haven't (fortunately) touched either of these screws, or the mounting screws.

I'm going to put the dust cover back!!! and protect the wire.

Thanks Dave, I didn't mean to confuse you, /ubbthreads/images/graemlins/blush.gif but you're the first to admit you're easily confused... :jester
 
Loud and clear Keoke, I'll be leaving that alone! Should I be worried there is no crimped metal band on the dust cover?
 
[ QUOTE ]

I'm going to put the dust cover back!!! and protect the wire.


[/ QUOTE ]
The "dust cover" is the only thing that protects the delicate contacts from moisture/water splash.

I would definitely secure the bottom of the cover with a zip-tie or something. Also, it would be good to seal the wire entry & any place else that water could get into the top. If the contacts don't make reliably the OD doesn't work. If the contacts fail to open, the solenoid will burn up in short order. The latter is why some folks fuse this lead. You can fuse it right where the lead leaves the OD relay on the firewall. (C2 terminal)
D
 
Simpler yet just switch the overdrive power wire from the unfused side of the 35 AMP fuse and reconnect it to the fused side. I think that's where it was originally intended to go but the forefathers got confused. As it is originally wired; in the event the solenoid fails or a short occurs in the wiring to it, the wire becomes the fuse---Keoke- /ubbthreads/images/graemlins/grin.gif
 
Yes Anthony, I initially used that method. Because the 12 GA wire will transmit the fault current to the fuse, or the little wire to the solenoid will become your salvation!. Presently, overdrive is powered off the horn circuit with its own dedicated 6 Amp Fuse.---Keoke- /ubbthreads/images/graemlins/driving.gif
 
If you use a heavy gauge wire, it will just let the lucas smoke out of the car somewhere else. Likely someplace that you would have rathered that the lucas smoke stayed in !
/ubbthreads/images/graemlins/cryin.gif
 
Thats correct ED, The smoke will come out of the fuse!, or we will sacrifice the little wire to the solenoid which is toast already.---Keoke
 
I have always wanted to use the phrase " let out the lucas smoke " in a sentence.
/ubbthreads/images/graemlins/spam.gif
 
Well ED ,Just do it!---Keoke- /ubbthreads/images/graemlins/laugh.gif
 
Aaaaahh, thanks?

I'll carefully replace the dust cover and seal, and zip-tie. I will also either swith the lead to the fused side of the block, or fuse the lead to the relay. I'd prefer not to "let the Lucas smoke out". Thanks all for your help.

BTW, my gearbox and OD are getting a slow, (i.e. extened, as I have a few minutes every couple of days) bath and showing their true colors.

Redline MT-90 will go in the gearbox/OD at some point soon.
 
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