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"dipping " the overdrive

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anthony7777

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just changed the headligt "dipping" switch in my bj7,as a result when im in overdrive and step on the dipping switch,it disengages the o.d.relay downshifting it under load,not good!checked the skizz-matic but can not disearn a relationship,someone tell me there is and its simple.thanks anthony7777 63 3000 M.K.II /ubbthreads/images/graemlins/frown.gif
 
Anthony,

When you changed the dip switch did you do any other electrical or mechanical work around the throttle switch, OD relay, instruments, etc?

Cheers,
John
 
john,thank you for responding so quickly,to answere your question,no,i did no other electrical changes adjustments etc,the reason i had to change the flasher unit it because when i changed all the groments,and subports for the throttle linkage,i bumped one of the terminals on the flasher and it popped off,im shure i replaced all three wires in the exact previous locations to the new unit,this problem never happened previously,ive tried to trace any association between all elect. components concerned and can not derive any cross in the wires,i did how ever relocate the new dimmer switch aprox. 2" ferther to the left of original location,ive been thinking perhaps i drilled into one of the wires that have to do with the mentioned relay wires etc,but i do not think they run near this location,thanks for the come back.a7777,still looking at the skizz-matic. /ubbthreads/images/graemlins/frown.gif
 
Anthony, Forget the Skizz-magic and get a new switch from a
different supplier.---Now guess who said dat- /ubbthreads/images/graemlins/grin.gif
 
ah,keoke,would that be shg? virginia will get p.o.ed at me if she finds out,check this,my wifes opinion, "if you need your high beams that means you cant see the road well,your going to fast,and this way when you step on the switch you will automaticaly slow down"she might have a point!but i didnt need to hear that after 5 hours under,in,and around my beast.to eliminate the posability of a bad switch,im going to remove the three wires from the flasher and manualy make and break contacts in various combinations and listed for the o.d. sol.click,if it does click,ill know its a hard wiring problem,if not,then ill know the switch is bad,any other "bright"ideas welcome.anthony7777 63 bj7. /ubbthreads/images/graemlins/frown.gif
 
What is the condition of your battery and battery connections including the battery switch? What is the condition of your generator? If you switch to high beams and you experience a voltage drop, the OD relay will drop out.
 
Anthony,

The voltage drop suggestion is probably correct but that could be caused by the new (inferior) switch. Is there enough left on the broken terminal to solder a piece of wire? Then you could reconnect the old switch temporarily and go for a test drive. If it works you need a new switch and another round for Keoke /ubbthreads/images/graemlins/thirsty.gif

Cheers,
John
 
big6 & johnloftus,my battery is very new,the condition of the cables,grounds,and my most favorite healey electrical component the "master batt switch"are all new having redone the entire trunk area this summer,of course that doesnt rule out a poor ground that may have just accured,as for the "dynamo"it was rebuilt/remanufactured just prior to my purchasing the car in may 2005,i have not had a chance to put a meter on it as of yet,but will do so this afternoon,all the lights are bright,and i didnt see a gen.worning light befor or after stepping on the switch.as for the old switch,well ive been taking things apart since im 3 weeks old [literaly] and couldnt resist opening this little jem up, it "was" very cool inside with contacts that flip around and all,but its since been placed in the universal recicle aperture,nothing that could have been saved of it,at least until i got my hands on it!i will take the advice of both you gentleman and explore the generator,grounds,switch,voltage drops etc,ill let ya know what i may find,keoke may have hit it on the first blast "get a different switch from another supplier" /ubbthreads/images/graemlins/yesnod.gif shg's gunna love to hear that one! /ubbthreads/images/graemlins/devilgrin.gif
 
Anthony,

The P.O. drilled out the rivets to disassemble my original Lucas head light dip switch and then used machine screws and nuts to hold it back together so I have pulled it apart to see the inner workings .. it is pretty cool inside, eh? You can still find the Lucas switches from some UK suppliers but not sure of the quality.

Cheers,
John
 
johnloftus,that was my intent also to rebuild it,but the pieces that comprise the rectangular barrels were too severly worn,however i did have the rivet gun and mach. srews on the bench!i know zackaly what ya mean. /ubbthreads/images/graemlins/yesnod.gif
 
[ QUOTE ]
guys,my reff. to the "flasher" was ment to be "dipper" switch,so solly! /ubbthreads/images/graemlins/tongue.gif

[/ QUOTE ]


/ubbthreads/images/graemlins/savewave.gif-Man this guy is really confused.---Keoke- /ubbthreads/images/graemlins/devilgrin.gif
 
Hi Anthony,
Maybe I can "add" to the confusion.

I'm assuming that the OD only drops out when the headlights are on? A very important clue. you didn't really say. Also you didn't say if the headlights dim or anything unusual when you push the HL dimmer & the OD drops out.

The only common point between the OD & the headlights is at the voltage regulator "B" terminal. A high resistance connection on one of the several connections at the B terminal could cause a voltage drop at the OD when the headlights are switched. As could high resistance in the wire from the "B" regulator terminal to the starter solenoid main feed terminal from the battery.

The feed circuits can be isolated at the fuse block #3 terminal.

The only other thing could be that the dimmer switch or it's wiring are shorting to ground. This should be easy enough to check with an ohmmeter while operating the dip switch.
D
 
Anthony,
Just put a volt meter on the battery and check your "not running" battery voltage. Start the car and see if the voltage goes up a bit ( indicating your generator is working at a high enough potential to charge the battery. Watch the running voltage when you turn on your head lights, it should stay above the "not running battery voltage". If all is OK, turn on the high beams. Check the voltage again. If it remains where the voltage regulator should be set, the problem is not with the dynamo or battery (I bet it doesn't). I like the idea of a voltage drop causing the OD solenoid to drop out. Let us know.

Jon
 
[ QUOTE ]
I like the idea of a voltage drop causing the OD solenoid to drop out. Let us know. Jon

[/ QUOTE ]
It would take a very large voltage drop to cause the problem. Once the OD solenoid is engaged, & only it's holding coil is energized, the normal situation BTW, the solenoid will remain operated until the voltage to it drops to six volts or less. Very unlikely that the battery and/or generator is going this low. Much more informative to put a voltmeter at the OD to OD relay connection & then work back toward the source.
D
 
daverussell,id recently changed the "flasher" unit due to bumping it and breaking of one contact,but did not notice the problem when i did that,i subsequently changed the "dipping" switch,and then began to have the downshifting/disconecting of the o.d. sol, when stepping on the "dipping switch" to get high beams while in overdrive. /ubbthreads/images/graemlins/yesnod.gif
 
problem solved! i finaly got a replacement dip switch n.o.s. that was not very easy to find installed it and all lines of communication between the o.d. relay and the head light dip switch have been severed,as john loftus suggested i found that the inner workings of the first after market replacement switch had an internal short causing a voltage drop to the o.d sol. causing it to drop out, the voltage drop also caused the left front head light to give up the ghost,i replaced both head lamps with "sylvania" 7" halogen "extravision" h6024xv, from auto zone $9.00 very bright and very pleased! "onward and upward"
again thanks all for your generous replys 7777. /ubbthreads/images/graemlins/savewave.gif
 
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