727 Low and reverse band... This can't be right

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Cole Andews

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Was having problems with my 727 kicking down so I thought I'd take the pan off and adjust the low and reverse band. The transmission is an unknown TCI that I found behind a crate engine. I've driven it about 50 miles trying to adjust the cable to get it to kickdown properly but I think I found the problem. How hard is it to replace these?

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Cole Andews said:
Was having problems with my 727 kicking down so I thought I'd take the pan off and adjust the low and reverse band. The transmission is an unknown TCI that I found behind a crate engine. I've driven it about 50 miles trying to adjust the cable to get it to kickdown properly but I think I found the problem. How hard is it to replace these?

View attachment 1715213059

View attachment 1715213060
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DEFINITELY wrong. Looks like the spring keeper let go...maybe to stiff of a spring?
 
I don't think that arm will swing out of the way enough. You have to remove the tail housing to get the pin out. Not horrible to do in car.
 
mattr927 said:
I don't think that arm will swing out of the way enough. You have to remove the tail housing to get the pin out. Not horrible to do in car.
Click to expand...

You're right about that, especially in this case.. You can get lucky, sometimes, by backing the adjuster all the way out. But that spring looks pretty stout..
 
That almost looks like an accumulator spring. I bet that spring slowed down the application of the band and I think that was your original complaint.
I suppose,that big fat spring wrecked the thin tin retainer first. Then if the servo came up too high,(not likely, but possible),it couldda spewed fluid out the top and there went your clamping pressure.If this could or did happen, very likely the servo would have wrecked the lip seal on it's way back in.And that would lead to slippage of the band as well. If it was me I would do an air-pressure test with the VB off, trying to prove that. And if I was not satisfied with the test, I would pop it outta there for a look-see.
I think I have replaced that spring with the VB on, but had to dislocate the apply strut to do so. In your case I think I would drop the VB and inspect the accumulator spring, and compare it to this blue monster.
Alternatively, maybe someone will chime in who is more familiar with the TF than am I, (which shouldn't be hard,lol).
 
I've done this repair a few times.
A coupla times I was able to fiddle the piston back in, but it was easier/quicker to just remove the tailshaft housing bolts, very carefully move the housing back using a sharp scraper to separate/save the gskt.,move housing back less than an inch, clock the housing enuff for lever pin to be removed.
The piston was damaged a few times, and needed replacement.
There is a hi/po piston avail,as this is not an uncommon prob.
One of the ones I fiddled back in, came back needing replacement.
I leave the driveshaft in.
 
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inertia said:
I've done this repair a few times.
A coupla times I was able to fiddle the piston back in, but it was easier to just remove the tailshaft housing bolts, very carefully move the housing back using a sharp scraper to separate/save the gskt.,move housing back less than an inch, clock the housing enuff for lever pin to be removed.
The piston was damaged a few times, and needed replacement.
There is a hi/po piston avail,as this is not an uncommon prob.
One of the ones I fiddled back in, came back needing replacement.
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I'm thinking I'm just gonna need to replace most of what's in there, thanks for the help
 
AJ/FormS said:
That almost looks like an accumulator spring. I bet that spring slowed down the application of the band and I think that was your original complaint.
I suppose,that big fat spring wrecked the thin tin retainer first. Then if the servo came up too high,(not likely, but possible),it couldda spewed fluid out the top and there went your clamping pressure.If this could or did happen, very likely the servo would have wrecked the lip seal on it's way back in.And that would lead to slippage of the band as well. If it was me I would do an air-pressure test with the VB off, trying to prove that. And if I was not satisfied with the test, I would pop it outta there for a look-see.
I think I have replaced that spring with the VB on, but had to dislocate the apply strut to do so. In your case I think I would drop the VB and inspect the accumulator spring, and compare it to this blue monster.
Alternatively, maybe someone will chime in who is more familiar with the TF than am I, (which shouldn't be hard,lol).
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Thanks for the reply, I can wiggle most of it with my hands but we'll see how it goes
 
I think it was so out of adjustment that it moved to far and blew out the retainer

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Also it hard to tell in the picture but it looks like a double wrap band, and they move the lever further than a single wrap band
 
inertia said:
I've done this repair a few times.
A coupla times I was able to fiddle the piston back in, but it was easier/quicker to just remove the tailshaft housing bolts, very carefully move the housing back using a sharp scraper to separate/save the gskt.,move housing back less than an inch, clock the housing enuff for lever pin to be removed.
The piston was damaged a few times, and needed replacement.
There is a hi/po piston avail,as this is not an uncommon prob.
One of the ones I fiddled back in, came back needing replacement.
I leave the driveshaft in.
Click to expand...
inertia said:
I've done this repair a few times.
A coupla times I was able to fiddle the piston back in, but it was easier/quicker to just remove the tailshaft housing bolts, very carefully move the housing back using a sharp scraper to separate/save the gskt.,move housing back less than an inch, clock the housing enuff for lever pin to be removed.
The piston was damaged a few times, and needed replacement.
There is a hi/po piston avail,as this is not an uncommon prob.
One of the ones I fiddled back in, came back needing replacement.
I leave the driveshaft in.
Click to expand...

Do You you remove the valve body and push the pin out the other side towards the tailshaft or towards the engine?
 
Toward driveshaft, rear.
You'll see a tab on the tshaft housing that holds the pin in.
You just need to twist the housing enuff for pin to clear.
 
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Can be done in car, without removing tailshaft. Remove valve body. Completely back off adjusting bolt. There is enough"slop", you can get the band strut out. Then the lever will swing down, allowing enough room to fix.
 
Cole Andews said:
Looks worse than mine, any tips?
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Ya.....I pulled the transmission. ...not fun.
But you have to take it apart. ..not hard.
Ever worked on an automatic?
I never had and did a full rebuild with help from the guys here...

Jeff's 727 rebuild thread

Not hard and not expensive. ....

Think you wanna give it a try?
We'll get you through it!

Jeff
 
MrJLR said:
Ya.....I pulled the transmission. ...not fun.
But you have to take it apart. ..not hard.
Ever worked on an automatic?
I never had and did a full rebuild with help from the guys here...

Jeff's 727 rebuild thread

Not hard and not expensive. ....

Think you wanna give it a try?
We'll get you through it!

Jeff
Click to expand...

I was hoping I was just gonna replace this and pretend everything was fine and not have to do a full rebuild, hope it doesn't come down to that
 
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