Sticky Valve body??

[pedal2themetal]

Morning all, having a slight problem with my transmission..Low miles (62,000) 1975 Fury I'm thinking its the 727. anyway.. its very jerky going into 3rd. at part throttle (easy throttle) and flairs as well going in to 3rd. part throttle to hard throttle (RPMs going up before it shifts into 3 rd.)
Is this a sticky valve body? and can I fix it with a can of stuff?
any help well be appreciated
Thank You
tim

 

[Fran Blacker]

Do you have your kick down linkage on the car and properly adjusted? The kick down linkage controls pressure inside trans.

 

[turbine68rt]

Other than what Fran mentioned, some other things to consider are the (obvious) proper fluid level, as well as clogged filter, worn front clutch, sticking gov. You could remove the vb and go over it, and while it's out do air pressure checks on the servo and clutch ports.

 

[pedal2themetal]

yes had a shop put in a shift kit .. but it was doing it before and after the install and had them reinstall the kick down lever that came loose at the transmission during the motor rebuild.. Motor was very clean inside absolutely NO gunk build up in the valley or in the heads, barrens showed no ware So I'm sure the mileage is correct at 62,000 . It just had a bad timing gear (plastic gear) but I put in all new rings and barrens/seal anyway since I had it apart.
Thanks
tim

 

[turbine68rt]

Were you driving it for any length of time with the kickdown lever loose? If there is a lack of throttle pressure it could easily damage clutches.

 

[pedal2themetal]

Unfortunately I did drive it for quite awhile a year or better (since it should not have come lose during my rebuild of the motor it was lose apparently before hand) and since I've put a different 4 bb (different one since the shift kit was installed) on it I have had it unhooked but pulled all the way forward with a spring it still shifted the same except no kick down.. I did notice when the shop reinstall it. It did hold second longer and kick down very easily (light throttle added) but still had the jerky and flair with up shifting.
I was just hopping to save some $$ So I guess I need to bite the bullet and have it rebuild.

 

[493 Mike]

Well, it is 45 years old and the rubber seals don't get softer with age!
Mike

 

[Cranky]

With the kickdown lever pulled all the way forward, it probably was shifting early even with moderate throttle opening and that means the transmission has been operating with lower than normal pressures.

 

[Fran Blacker]

The trans lever should all the way back at full throttle to have max pressure. 40 years ago I was missing a piece of linkage to kick down linkage. A 396 Chovel and me were doing a little contest he quit at 75 mph. Trans slipped just as he quit. That's how I learned about trans work. Cooked all steels and clutches. OOPS!

 

[Darter6]

Sounds like the high gear clutch pack is leaving the train station...

 

[pedal2themetal]

HI and thanks for all the replies ,, I found this Informative and interesting in a google search. at this link,
Take care
tim

www.hotrod.com/articles/the-lowdown-on-stock-torqueflite-kick-down-linkage/

As the kick-down linkage/cable pushes the kick-down lever rearward, it increases line pressure inside the trans and initiates a downshift. "If you adjust the cable so the lever is at the front of its travel range at idle, the line pressure will not increase properly as the throttle increases," Jason Muckala of Motech Performance explains. "This makes the trans shift too early, and it can cause the clutches to slip and destroy the transmission. I've seen people install springs to hold the lever forward, but it's not supposed to stay in that position at idle." This photo shows the lever full forward; in this portion of the lever's arc you can feel no pushback from the lever, an indication that no increase in line pressure is occurring.
Somewhere in this range of the lever's arc, you can feel a slight resistance from the lever's internal spring. This is where the line pressure begins to rise, ultimately causing a downshift. Properly dialing in the lever's range of motion is critical to shift performance and transmission longevity. Says Jason: "For the first half of its travel range, there is very little resistance and the lever does nothing. At the halfway point, you can feel where it starts to hit the valve inside the trans, and that's the position the lever must be in at idle."
At WOT, the kick-down lever should be positioned at the end of its range of travel. This ensures accurate shift points and a proper increase in line pressure. Factory kick-down linkage setups can create scenarios where the kick-down lever will not move all the way back at WOT, or scenarios where the lever moves all the way back and hits a hard stop before WOT. Now you can begin to understand why it's important for the bellcrank on the throttle shaft to move in perfect sync with the kickdown lever on the trans in a 1:1 ratio.

 

[dvw]

The high gear clutch is slipping. Why? My bet is worn reaction shaft seals or worn/hard high clutch piston seals. This has then worn the high clutch frictions and more than likely hot spotted the steel plates. Time for a rebuild. There is no magic fix.
Doug

 

[Mick56]

I know people that swear this stuff works.

 

[pedal2themetal]

HI I adjusted the linkage like the above link suggested. Tho its not hooked to the carb I locked it in place for idle.. It shifts much better now with no jerking going into 3rd but it does still have a slight flair (raise in RPM before going into 3rd.) at easy throttle. I might try to add a little more rearward setting and see what that does and maybe some of the Lucas stop slip.. I think its just a friction modifier but it might help for the mean time..
Thanks to all who replied
Tim

 

[Fran Blacker]

Fix it right or you'll wish you had. If it's not to late already. If can't get linkage Locar has cable kit or somebody else.

 

[Wietse]

Simple way of setting it up:

-Set carb at WOT
-Push linkage all the way rear as far as it can go
-Adjust the linkage at the carb so that the link pin sits near the rear side of the slot
-Done

Now when your carb is at WOT the linkage gives maximum throttle pressure.

 

[66Satellite47]

Not sure how your adjustment will work if not connected to carb. If you have the kick down lever locked all the way back & it still "flairs" going into 3rd, I figure you're on borrowed time and will wreck the expensive hard parts. Just say'n.

 

[pedal2themetal]

Not sure how your adjustment will work if not connected to carb. If you have the kick down lever locked all the way back & it still "flairs" going into 3rd, I figure you're on borrowed time and will wreck the expensive hard parts. Just say'n.

HI NO its not locked all the way back just back to where I can feel the spring inside give a little tension on it like in the link I posted.. but I am going to adjust it to all the way back at WOT once I fab the linkage so it well let me do so.. I need to grind the slot farther back to allow full throttle before it bottoms out against the stop in the transmission.

 

[oldkimmer]

No u don’t need to grind the slot. Post pics so we can help u get this right. What linkage do u have. Kim

 

[Demonic]

Tho its not hooked to the carb I locked it in place for idle..

That is a bad plan. Get a throttle lever adapter and connect the linkage properly. I suspect the clutches need to be replaced already in your trans. If you're inclined, it's not a hard job.