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Throttle switch and linkage

gsable

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OK folks, here's the story. I bought a 1967 BJ8 a few months ago with 38,000 miles on it (maybe?). The bottom wire on the throttle switch was not connected and there was no linkage from the throttle switch to the throttle linkage. When I inquired to the previous owner why the lower wire was not connected, he responded that you don't have to hit the accelerator to disengage the overdrive; just throw the overdrive switch on the dash and it will disengage the overdrive automatically. He was right and it works just that way. However, I have read that the purpose of having to hit the accelerator is to reduced "shock" to the transmission when switching the overdrive off.

As stupid as this sounds, I never noticed that the linkage was missing from the throttle switch. So I am now going to replace the missing linkage but I don't know what position the shaft coming out of the throttle switch should be in when I connect the linkage.

Any guidance would be appreciated.
Gary
 

Keoke

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Hi Gary, The shaft is positioned so that the switch is at the heel of the cam inside the assembly. Yes, operating the OVD in the bang bang mode without using the clutch can shock the tranny.--Fwiw--Keoke

Alternate check: the slot in the shaft should be vertical when the linkage is connected. Initially it may be right if not rotate it 180 Deg.
 

vette

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Gary, I''m sure that you would rather have the O/D work as intended, but I thought I would mention that there are many examples of people running O/D with out the throttle switch. My own BJ7 has no throttle switch. and yes you do want to have at least a slight bit of excelleration on when I shift the O/D to minimize the shock to the driveline. Of coarse on hard excelleration when running it uup thru the gears you will have any amount of pedal down up to maybe evern full pedal in 4th gear when you might shift into o/d. but on downshifting out of o/d, be sure to at least have some amount of acceleration on. Never let the o/d shift on decelleration. One my car, when when I am coming to stop signs, traffic lights or off ramps from the interstates, I just give it 'just a touch of pedal' just when I hit the switch manually. It makes for an interesting and fun decelleration approaching a stop because just as you are decellerating to the stop, you give it just a slight blip of the throttle, flip the switch down hear the revs and exhaust note climb for an instant and then your on the brakes to make the stop. Gobs of fun. If you make a quick stop in overdrive and havn't have the time to bring it out of o/d before the stop, you can shift it out of o/d while sitting still at the stop, with no ill effects.
 

Dave Russell

Yoda - R.I.P
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Here is a simple diagram of the various switches & relay & how they work.
D
 

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TomFromStLouis

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Excellent info Vette. I need these kinds of tips!

And it seems much better to get them here rather the pretending I did not see the amused snicker of the helpful club guys. /bcforum/images/%%GRAEMLIN_URL%%/blush.gif
 
OP
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gsable

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Thanks to all for the info. You guys are a wealth of knowledge. Why did I spend monry on all those books and manuals that never have the answers when I have you.

Thanks again,
Gary
 
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