700R4 TV/Detent Cable Setup Procedure
Thread Starter
Instructor
Joined: Feb 2017
Posts: 209
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From: Iowa
700R4 TV/Detent Cable Setup Procedure
Hi all. I have an '82 car, but I figured I'd reach more 700R4 owners in the C4 section. I just finished a full rebuild of a 700R4 trans manufactured in 1988. My trouble comes in properly setting up the TV cable. I understand that for the adjustment to be correct, the plunger needs to be flush with the bushing at WOT.
The problem is that there is so much effort required in making this happen, that something is bound to break, bend, or snap. I took the linkage apart on the valve body, but nothing appears to be stuck or out of the ordinary. The TV valve itself is free and moves smoothly. The spring also appears to be factory.
Does anyone have any suggestions as far as what is going wrong? I have never done this before, and I am at a loss. The cable is brand new and moves freely when disconnected. Help!
The problem is that there is so much effort required in making this happen, that something is bound to break, bend, or snap. I took the linkage apart on the valve body, but nothing appears to be stuck or out of the ordinary. The TV valve itself is free and moves smoothly. The spring also appears to be factory.
Does anyone have any suggestions as far as what is going wrong? I have never done this before, and I am at a loss. The cable is brand new and moves freely when disconnected. Help!
Thread Starter
Instructor
Joined: Feb 2017
Posts: 209
Likes: 21
From: Iowa
Wow! I really appreciate the quick and thorough response. This is all very new to me, and never having rebuilt a trans before, I am taking the time to do things right before I hop in and drive off.
Funny enough, I was actually able to get 3ish grooves to show and still reasonably open the throttle bodies to WOT. My service manual does state that the plunger should be flush with the bushing, but maybe that's only for pre-1987 transmissions. Looking in while the cable moves, it's clear that all mechanical advantage is lost when the plunger is less than 3 groves showing. The cable is more or less pulling at a 180 degree versus a 90 degree angle if that makes sense.
I didn't even think to look at the position of the throttle valve when I was assembling the valve body. It's being held in by a roll pin from the opposite side, so I'd have to take the VB off to observe its movement.
Basically, it sounds like I need to take the valve body off and look inside to see what the throttle valve is doing relative to the plunger and count the grooves. Is there any other way around it, or is this it?
Funny enough, I was actually able to get 3ish grooves to show and still reasonably open the throttle bodies to WOT. My service manual does state that the plunger should be flush with the bushing, but maybe that's only for pre-1987 transmissions. Looking in while the cable moves, it's clear that all mechanical advantage is lost when the plunger is less than 3 groves showing. The cable is more or less pulling at a 180 degree versus a 90 degree angle if that makes sense.
I didn't even think to look at the position of the throttle valve when I was assembling the valve body. It's being held in by a roll pin from the opposite side, so I'd have to take the VB off to observe its movement.
Basically, it sounds like I need to take the valve body off and look inside to see what the throttle valve is doing relative to the plunger and count the grooves. Is there any other way around it, or is this it?
Thread Starter
Instructor
Joined: Feb 2017
Posts: 209
Likes: 21
From: Iowa
Unfortunately, that method was what I tried first. My cable has the grooves, and looks like it will ratchet, but it doesn't. From what I understand, not all cables are the ratcheting style. That being said, my second train of thought was to just adjust the WOT cable position to allow the plunger to be fully depressed. With the cable set for that configuration, the accelerator pedal in the car doesn't have near enough strength to open the butterflies fully. If I had to guess I'd say they're 3/4 open. Without the cable attached they do open all the way.
I hope I'm missing something obvious here, but I can't help but feel I've checked almost everything. I just know this is such an important step to get right. Any more ideas, please send them my way!
I hope I'm missing something obvious here, but I can't help but feel I've checked almost everything. I just know this is such an important step to get right. Any more ideas, please send them my way!
