Jeff's 727 rebuild thread

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Yes I do. At least it wouldn't have deformed itself & bent past the snap ring. Dont forget, the return spring you fitted from the TF-2 is considerably stronger than the stock item which didn't help the matter. What I also like to do is put a 008" steel shim between the spring & the aluminium retainer to prevent the spring wearing into it.
 
KickDown said:
Yes I do. At least it wouldn't have deformed itself & bent past the snap ring. Dont forget, the return spring you fitted from the TF-2 is considerably stronger than the stock item which didn't help the matter. What I also like to do is put a 008" steel shim between the spring & the aluminium retainer to prevent the spring wearing into it.
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OK.....billet.

Onward and upward.....I'll be getting into the valve body this week as time allows.....detailed pictures will be coming.
The general consensus is I got something wrong in the 1-2 shift valve or it's just plain stuck for some reason.....

Jeff
 
Without wanting to unnesessarily get your hopes up, in the shop this evening I tore into a 727 VB to see if I could find a reason for your no Breakaway 1st gear in D. I studied the 1-2 shift valve in particular. Now it is possible to fit this valve the wrong way in the valve body. I am not saying this is your case & I also dont know how it would affect the shift characteristics, but it can be fitted the wrong way round & the end plate will fit without issue. In the TF-2 installation instructions there are no illustrations of the shift valves, but the middle picture on page 113 of Carl Monroe's Book shows the correct orientation. Maybe it's as simple as that.
 
KickDown said:
Without wanting to unnesessarily get your hopes up, in the shop this evening I tore into a 727 VB to see if I could find a reason for your no Breakaway 1st gear in D. I studied the 1-2 shift valve in particular. Now it is possible to fit this valve the wrong way in the valve body. I am not saying this is your case & I also dont know how it would affect the shift characteristics, but it can be fitted the wrong way round & the end plate will fit without issue. In the TF-2 installation instructions there are no illustrations of the shift valves, but the middle picture on page 113 of Carl Monroe's Book shows the correct orientation. Maybe it's as simple as that.
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I'm honestly thinking (hoping) it's exactly that.....I have that book and have been looking at diagrams on Google....
That is actually the first thing I'm going to carefully check for as I take it apart.....because if it's possible to put in in backwards....I probably would....LOL!

Here's hoping! That would explain it for sure!

Jeff
 
I trimmed the strut down .125" and everything is fine now.....the drum fits in the band.....

Now I can take a look at the valve body...



Jeff
 
If you open Tom Hand's book on page 109, the bottom right photo shows the PTKD module. It houses a throttle plug & limit valve & allows a downshift from 3-2 without going all the way to WOT detent.
 
KickDown said:
If you open Tom Hand's book on page 109, the bottom right photo shows the PTKD module. It houses a throttle plug & limit valve & allows a downshift from 3-2 without going all the way to WOT detent.
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I'll have to check!

Jeff
 
OK Jeff. No worries! After what I learned in the shop this afternoon I am convinced your 1-2 shift valve is in the wrong way round. I disassembled 2 VBs. One with PTKD & 1 early model without, just to see if there is a difference. The difference is in the geometry of the 1-2 shift valve, but they both work in the same way.
The valve must contact the 1-2 govenor plug when the car is at rest. If the valve is in wrong, due to the diameter of the lands on the valve it will not make contact. The 3 lands all look the same diameter but the innermost land is 0.012" smaller. Also with the vehicle at rest the valve will not cover the channel that feeds line pressure thru the channel casting to the front servo piston, applying the piston & giving you 2nd gear at rest. A quick & painless fix. I dont have anything else if I'm wrong. I'll have to do some serious homework. LOL
 
KickDown said:
OK Jeff. No worries! After what I learned in the shop this afternoon I am convinced your 1-2 shift valve is in the wrong way round. I disassembled 2 VBs. One with PTKD & 1 early model without, just to see if there is a difference. The difference is in the geometry of the 1-2 shift valve, but they both work in the same way.
The valve must contact the 1-2 govenor plug when the car is at rest. If the valve is in wrong, due to the diameter of the lands on the valve it will not make contact. The 3 lands all look the same diameter but the innermost land is 0.012" smaller. Also with the vehicle at rest the valve will not cover the channel that feeds line pressure thru the channel casting to the front servo piston, applying the piston & giving you 2nd gear at rest. A quick & painless fix. I dont have anything else if I'm wrong. I'll have to do some serious homework. LOL
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That's awesome.....makes me want to open it up TONIGHT and verify (verify I'm a dumass!)
A backwards valve could cause ALL manner of problems I'm sure.....
Like I said, gimme a 50/50 and I'll get it wrong every time!

Jeff
 
Dumbass Jeff? I dont think so. You've done a sterling job & one a lot of people would farm out. You've learned a heck of a lot that you didn't know this time last year & nobody can take that experience away from you. You're gonna win this!
 
KickDown said:
Dumbass Jeff? I dont think so. You've done a sterling job & one a lot of people would farm out. You've learned a heck of a lot that you didn't know this time last year & nobody can take that experience away from you. You're gonna win this!
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Thanks....!
I must say, transmissions were a "black box" to me....they just worked but I didn't know how.....
But now I have a MUCH MUCH better understanding of them now - and I'm not afraid to dig into one now!
It really has been fun! (Except pulling it out a second time! LOL!)

Jeff
 
Ok.....here is the orientation of the valve as I pulled it out. ....looks like it was correct....yes?

image000001.jpg

It was a little "sticky".....I had to fiddle with it to get it out.....
Don't know what to think now....Hmmm.....

Jeff
 
Polish the valve lightly with some scotchbrite, make sure it is perfectly clean, put a little atf on it and put it back in. It should slide in and move without any hang ups.
 
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d55dave said:
Polish tbe valve lightly with some scotchbrite, make sure it is perfectly clean, put a little atf on it and put it back in. It should slide in and move without any hang ups.
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Will do....just wondering if that was my shift issue or not now.......
Was kinda hoping I had it in backwards. ....!


Jeff
 
Any chance your throttle pressure valve was put together or adjusted wrong? Excess pressure and force on the band could have caused the break and possibly shift issues?
 
d55dave said:
Any chance your throttle pressure valve was put together or adjusted wrong? Excess pressure and force on the band could have caused the break and possibly shift issues?
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Guess I'll be checking that next....thanks!

Jeff
 
Can anyone please better explain how to adjust the line pressure and throttle pressure settings?
Maybe my issue is there???

2018-03-15_05h44_41.png


Jeff
 
d55dave said:
Polish the valve lightly with some scotchbrite, make sure it is perfectly clean, put a little atf on it and put it back in. It should slide in and move without any hang ups.
Click to expand...
First of all Jeff. Yes you got the valve in the right way so no worries there. Then this^^^^^what Dave said. With the TF-2 the line pressure is readjusted so the small plate on the line pressure adjusting screw assembly is just flush against the adjusting screw bracket. Adjust the throttle pressure screw so you can just get the 3/16 drill in the TF-2 Kit between the tab on the throttle lever assembly cam & the TP adjusting screw head without depressing the kick down valve.
 
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Just a thought, but go back to page 4 of this thread & check Tracy's post #98 again. Could be something there, but if you had 1st gear in D before you tore it down, maybe not.
 
I've been under the weather for a couple of days but feeling better and ready to get back to work on this now!

I spoke with Tom Hand about it and he thinks it's probably the govenor. ..

Tom said:
"Look closely at it. usually, the throttle pressure circuit is goofy or the governor is goofy to make it not drop into low and only do it when you manually down shift."

So tomorrow morning I'm going to really go over those 2 areas...

Any thoughts on what I should look for regarding the govenor?

Jeff
 
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