727 TF3 problems and pressure test

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CopperheadDart

CopperheadDart

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727 question! Freshly rebuilt 727 with TransGo TF3 kit. Low seems to be binding up. One time I couldn't even get it to pull itself in the shop. Did a short road test and shifts didn't seem very firm.
Adjusted bands according to TF3 instructions.
Just did pressure tests on front, rear, and line.
Testing the rear servo pressure, 1st gear showed 90psi, and reverse maxed the gauge past 400.

Line pressure test showed around 100 in all forward gears.

Front servo showed 90-100psi in 3rd gear only, and that seemed to flutter a little. Anyone have any insight of what I need to look for?
 
Did u adjust the new manual valve properly? What I mean is did u bend the linkage arm so the valve sits in the proper place. What year is the tranny? Case? Could be that u don’t have the shift linkage set correctly or the wrong linkage. Kim
 
Did you check the end-play after the front end went in? This might help diagnose if the front clutch is properly engaged on the splines of the rear clutch.
Otherwise, since the pan is off, no better time to airtest the servos etc.
 
Update!
Took out the VB, again, air tested, servos and bands operating, etc... ended up calling TransGo on the matter and they said to add a tv cable. We only had experience with older TF3 kits where tv cable was eliminated, but apparently the kits out now still require it. So we happened to have an ebay kickdown cable (looks just like a Lokar), fabbed up some bracketry, installed and adjusted it. Reinstall vb and all works fine! Three gears of fun and solid shifts.
No where on the TF3 kit instructions did it mention the use of the cable, but that fixed our woes.
 
What did you do with throttle valve lever initially? Leave it sit at rest or wire it all the way back??
 
oldkimmer said:
Glad u got it fixed. When I do a TF3 for the street I install the kd. Kim
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I wired mine back but often wonder how that affects longevity running on the street (I do see plenty of track time as well)
 
Wired all the way back is like running the KD wide open all the time. The line pressure gets maxed out and the shifts are very firm, often borderline harsh. If the Governor is still working, the auto up-shifts will be quite late.
But there is nothing stopping you from backing off the tie-back some, just not all the way.
 
AJ/FormS said:
Wired all the way back is like running the KD wide open all the time. The line pressure gets maxed out and the shifts are very firm, often borderline harsh. If the Governor is still working, the auto up-shifts will be quite late.
But there is nothing stopping you from backing off the tie-back some, just not all the way.
Click to expand...
There was someone on the forum who mentioned using a choke cable to be able to adjust the throttle valve. I may look into that for occasional street use, maybe set it with a very limited range, half of the tv levers travel. Choke off position and the TV is maybe half way (find a happy medium) and then with the choke pulled out the tv is all the way back (for the track /spirited street). The TF3 is full manual, no auto function
 
Seems kindof a long-way around the block, since Chrysler already engineered a KD system.
I have not installed a TF-3 for over two, maybe even three decades. Back then, the TV and it's spring, IIRC was replaced with parts supplied in the kit, the line-pressure jumped up, and finally, the lever was tied all the way back; and all that was in the instructions.
Back in the early 80s; I set up one of my own that way, for a streeter, and within a week or so, I swapped everything over to TF-2 status.
TF-2 does everything TF-3 does, but with much improved street-driveability. After that, all my auto-cars have been TF-2'd.

I realize that you are coming from the other side, so, probably not telling you anything that you don't already know.
 
AJ/FormS said:
Seems kindof a long-way around the block, since Chrysler already engineered a KD system.
I have not installed a TF-3 for over two, maybe even three decades. Back then, the TV and it's spring, IIRC was replaced with parts supplied in the kit, the line-pressure jumped up, and finally, the lever was tied all the way back; and all that was in the instructions.
Back in the early 80s; I set up one of my own that way, for a streeter, and within a week or so, I swapped everything over to TF-2 status.
TF-2 does everything TF-3 does, but with much improved street-driveability. After that, all my auto-cars have been TF-2'd.

I realize that you are coming from the other side, so, probably not telling you anything that you don't already know.
Click to expand...
Main reason I went with the TF-3 was to ditch the Lokar kickdown setup that I tried on the initial TF-1 I had installed (I never had the factory rod and bell crank setup to begin with which is the only setup I’d ever consider running knowing what I know now) The Lokar kd added way too much resistance to the throttle on my van (unique throttle setup vs a car) Just made the throttle too stiff.
But being I’m using a PPP shifter, I went to the TF-3 to eliminate the kd and anyway I rather enjoy having the lever in hand with full control, connected all the time. But you are correct: the 2 does everything the 3 does
 
Ok; I get that, and yes I know about that van gas pedal system. I had a 77 for a while.
It had a terribly lean 2bbl on it and one of the worst timing curves I ever stumbled on.
Not to mention trying to read the timing! I finally drilled a hole in the bellhousing...... from the cab, and installed a TDC mark on the ring-gear. I worked on that tune for a lotta hours. But in the end, she ran daymn good.
 
AJ/FormS said:
Ok; I get that, and yes I know about that van gas pedal system. I had a 77 for a while.
It had a terribly lean 2bbl on it and one of the worst timing curves I ever stumbled on.
Not to mention trying to read the timing! I finally drilled a hole in the bellhousing...... from the cab, and installed a TDC mark on the ring-gear. I worked on that tune for a lotta hours. But in the end, she ran daymn good.
Click to expand...
Vans are a real challenge to work on, but the ability to see the timing with the doghouse off is a great mod!
 
Ricks70Duster340 said:
Vans are a real challenge to work on, but the ability to see the timing with the doghouse off is a great mod!
Click to expand...
Yes, as well as tuning on the carb without getting in and out popping the hood, among other things
 
Ricks70Duster340 said:
While tuning, I used to drive with the doghouse off so I could see the carb in action and listen to the engine in general.
Click to expand...
Exactly. And, if running an AFB or similar carb with metering rods you could swivel those covers over just enough to see the pistons rising and falling. Made dialing in the springs a cinch.:thumbsup:
 
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