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Need some 700R4 help...back together post 64!

Interesting, wonder why it has so much pressure?

So this excess pressure is holding the tv valve and not letting it shift, right?
 
The TV is stuck, causing too much pressure. The high TV is why it won't shift out of 1st. The valve body thinks the throttle is open and you're not able to get enough governor pressure (i.e. driveshaft speed) before the engine runs out of revs.

Since you have the gauge, you can disconnect the TV cable from the throttle and feed it in and out by hand (tranny in park). If the valve is working, the line pressure should respond.
 
Does it feel like its doing anything when you move the cable? I'm wondering if the cable has come unhooked from the valve.
 
Yea it would snap back a bit, so I think it's still hooked up.

I've drained the pan again and going to remove the valve body again and go over it, removing each valve...

I guess it's possible something got stuck In there during my reinstall or maybe during the flush, who knows :)

I ordered up a new VB gasket so that'll be here in a couple of days, enough to thoroughly clean this thing and have another look around.
 
If everything is fine in the trans and the cable is disconnected, it will default to low pressure.
 
Well now something interesting... First the gasket and plate...lost a ball from the lower left corner somewhere...see pic. I have an idea where but not quite sure as I was holding the body up trying to keep my balls out of the street lol. The gasket on the VB side was torn in a couple of spots as well, most notably where the 1-2 accumulator resides...missing about 1/4" of material.

On the body itself, the tv was stuck from the spring on the back side, and both small valves next to the tv that face towards the front of the truck were stuck.

Lots of a grease like substance throughout the valve body, but not much if any in the pan itself.

For the tv return spring, it looks like the spring got wrapped around the shaft and kept the tv frozen in place. The PO had a shift kit with the improved tv valve and anti stick spring...

So when running, pressure pushes on the back side of the valve and the tv cable pushes the plunger against the spring which pushes against that valve, right? If I did away with that return spring would I cause myself any heartache later? The valve moves freely back and forth, but there is no detent to center the valve, which is why I'm asking about pressure vs that valve and which side it's on.

image.jpg
 
The grey grease stuff doesn't do you any favors. It's partly metallic. You should clean that valve body while it is out. The safest way it to remove one valve at a time. Brake cleaner works fine to clean the junk out.

The original design has the inner-most section of the TV floating with only hydraulic pressure to push back against it. So the spring technically isn't needed on a stock valve. But you make it sound like an aftermarket valve. It's important to know what's in there. Maybe you can take the TV apart and post a picture? You should have a manual or the valve body diagrams at least to compare to.

The old gasket may or may not be working OK, but why not pick up a new set while it's apart? For any parts you need, any mom and pop type transmission shop should be able to hook you up.
 
Here's the checkball locations:

700-R4_36.jpg


If you're setting them on the spacer plate instead of in the transmission case, then you need to see it backwards:

700-R4_36_checkballs.jpg
 
Can you show how this spring was hanging up on the valve?

The good news is that a problem like this is a real "smoking gun" to give you confidence you are fixing something and not just putting it back together with the same problem.

How does the valve bore look? You'll have to assess whether that valve is going to work in there or not.
 
I'd be stoked if this is the smoking gun for sure...

The bore itself looks really clean, no pitting that I can see. The valve moves back/forth cleanly, I'm just concerned that without the return spring it may not work correctly...

I do have an OEM valve I picked up, but I think this may work. I also have a spare valve body now too, complete with valves :)

In the pic, the spring gets a bit bound up on the grooves on the end of the valve. Also with the spring in the valve body, the valve won't move all the way to the end of the bore (towards the front of the vehicle). Not sure if that matters

image.jpg
 
That spring should be pushed up farther on the valve till the small part of the spring is seated on the back side of the first large land on the valve. It is made to collapse upon itself as the valve strokes, not having it seated this way could cause it to bind up the valve.
 
If it goes up further, it won't let the valve move in the bore. Basically i think it's grabbing the valve and not letting it move.
 
It's been years, but I think the spring in mine is smaller. It only touches the very tip of the valve. It would look like this with yours:

aftermarketTV.jpg


But the black valve doesn't seem to have the little tip on it that the spring rides on. In this image, you can see how a small spring could sit on the end of the stock valve and hardly restrict full motion of the valve.

image063.jpg


If the spring is hanging things up, I would definitely want to run without it. A clean stock trans can go for years with no spring there and shift fine. Maybe Greg can give some advice for what's best at this point - stock valve, black one, spring or no. Maybe you can figure out who makes that black valve and get their advice.
 
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