Morning Sickness

[Dart50]

Looks like I need to take the pan off my 727 so it is probably time to deal with the morning sickness.
I saw one thread where someone suggested that drilling a hole (separator plate?) would pump fluid to the converter while in park. Unfortunately they did not give details . Anyone done this or have details?

The other suggestion I saw was the Trans-go shift kit.
All suggestions welcome.

Thanks

 

[TrailBeast]

If it has morning sickness you need to do it eventually, and you might as well put the TF2 kit in it while it's apart.

The fluid circulation in park will be solved with the new manual valve in the kit.

There are two symtoms that could be called morning sickness.

1. wont go until the trans warms up awhile (caused by seals and rubber parts hardening up)
2. wont move for a few seconds after sitting for awhile (maybe overnight)
This one is caused by converter drain back.

Number one is actual morning sickness.
Number two is a worn pump and/or pump bushing.

 

[fishy68]

The older Trans-go kits told you to drill a part in the valve body casting (not the separator plate as you were told) but they now come with a different style manual valve that eliminates drilling. The reason they got away from drilling is it actually allows the converter to drain back worse when sitting.

 

[Dart50]

Thanks for the feedback.

Maybe I jumped to the wrong conclusion for my transmission then.
I would appreciate your help in confirming my problem based on your comments.
The car is always fully warm before I move it and there is a minimum of 24 hours between times I use the car (often more).
Typically I tinker with the car at night and when I am done I start it and let it warm while I clean up the tools. The temperature of the engine is always around 180 before I move it.

If I just put the car in drive after it is warm it feels like the transmission is slipping for the first 100 yards or more.
If I climb in the car and shift into neutral for ~ 30 seconds or more before I shift into drive I get a clank from the front U joint (on to-do list) and the transmission works as expected.
I don’t want to install the shift kit to find out that the issue was really hard seals.
Your thoughts?

 

[TrailBeast]

Thanks for the feedback.

Maybe I jumped to the wrong conclusion for my transmission then.
I would appreciate your help in confirming my problem based on your comments.
The car is always fully warm before I move it and there is a minimum of 24 hours between times I use the car (often more).
Typically I tinker with the car at night and when I am done I start it and let it warm while I clean up the tools. The temperature of the engine is always around 180 before I move it.

If I just put the car in drive after it is warm it feels like the transmission is slipping for the first 100 yards or more.
If I climb in the car and shift into neutral for ~ 30 seconds or more before I shift into drive I get a clank from the front U joint (on to-do list) and the transmission works as expected.
I don’t want to install the shift kit to find out that the issue was really hard seals.
Your thoughts?

That is converter drainback and the shift kit with the new valve should take care of it.
Or you could just change the valve and not put a shift kit in it. (either way)

The best way is to pull the trans and remove the pump to measure the gears and replace the converter bushing and seal but not many would do it that way.
(The bushing and gear clearances are what causes drainback) but the new valve allows the fluid to circulate in park, and this refills the converter soon after the engine starts anyway

Hardening lip seals can be more or less diagnosed by starting the car and put it in neutral right away.
Then after that 30 seconds put it in gear, and if it engages in forward and reverse as soon as you put it in gear then the seals are probably ok.
The dead giveaway on lip seals is if you have to rev the engine before it will engage a gear when cold. but goes right in at idle when warm.

 

[fishy68]

I agree with TB that the problem is the typical torqueflite converter drain back issue. There is one more thing that can also add to the problem and that's worn reaction shaft sealing rings and/or grooves worn in the front drum. If the trans works right except for that problem I'd just slip it in neutral for 30 seconds before driving it and not worry about it

 

[Dart50]

Thank you for taking the time to write this up.
Replacing just the valve looks like the best fit for me right now.

The “Best Way” fix will have to wait for another day unless the transmission develops some new problem that forces me to pull it out. This is the first time I have seen someone document the causes of drain back. Thanks

I am saving the details of this thread in my to-do list in case I ever have the time to fix the root problem. This list is getting way too big!

I was just going to stick with the 30 second wait in neutral until I decided I was going to pull the pan for other reasons. I figured while I was in there I would deal with this item too.

Thanks again