727 push button trouble

[petritl]

I know this isn't a B platform vehicle but I am hoping there is someone with 727 knowledge that will help me. Last fall I removed a 1962 Chrysler 300 from a shed where it had been sitting since 1978 the car it now runs, drives and stops on it's own but the transmission has a problem.
If you are stopped and the drive button is depressed the trans slips bad, when you depress the L button you can feel the transmission engage and the car moves forward normally, while the car is motion if you depress the 2nd gear button it shifts fine into 2nd and when Drive is depressed it goes into drive. While in Drive the trans seems to shift between 2nd and 3rd and the passing gear (WOT)downshift from 3rd to second works but when you stop the trans slips bad. You have to go through the gears manually again.

If you try and take off in second, the trans does the same thing (just slips)
Reverse seems fine.
I recently put some trans-x in the transmission fluid hoping it would remove any vanish that may have accululated on the transmission valves but it hasn't made a difference yet.

 

[wedgie]

Sounds like a linkage adjustment problem to me. Pull the pan. You should probably change the fluid anyway (use type F). While watching the rooster comb and the neutral safety switch, and having an assistant push the different buttons, you will see very clearly which way to adjust the cable. You can get a precise adjustment this way. When you change the filter, be sure to get one for a pre '66 trans as it will have two holes and the later ones have only one hole as they have no rear pump. This process has always worked well for me.

 

[SUPERSTOCKRACER]

drop the pan and make sure your dial is adjusted correctly. make sure when you put the car in nuetral, your detent is right on the nuetral safety switch. if your off a little, youll get what your saying .slippage.
turn outside dial till your on nuetral correctly, then push all your buttons and go back to nuetral and see if its still in the center. adjust if necessary.then do it again.

 

[RTSrunner]

J am no auto trans expert,but I have been doing some research on 727's lately.My '65 Coronet has a 727 tat has been sitting for a while and i wanted to go through it before installing it.The clutches were losing the friction material as it was delaminating from the discs,The steel discs also had some wear and bluing.The seals and o-rings were dry and not as pliable as they should be.All the above would have been problems if I tried to use it as is.My valve body also had a crack in the valve boy at the port where pump pressure enters.Apparently it is a common probably for my valve body casting number.On your transmission,you could have a rear clutch problem.In drive the rear clutch is used for low gear.When in manual low the low/reverse band is applied for first gear,which may be why you have forward in that mode.A fluid/filter change might be a good first move though.
Ron

 

[hemistix66]

Superstockracer&RTSrunner are on the money.I had a push in my 63,after the rebuild i had same problem.Once I learned how set detent it worked fine.Check the filter parts store gives you too!

 

[petritl]

Thanks for your advise...The next time I get over to my friends place to work on the car I will change the fluid/filter and check the cable adjustment.

I post the outcome.

Regards,Tad

 

[petritl]

Sounds like a linkage adjustment problem to me. Pull the pan. You should probably change the fluid anyway (use type F). While watching the rooster comb and the neutral safety switch, and having an assistant push the different buttons, you will see very clearly which way to adjust the cable. You can get a precise adjustment this way. When you change the filter, be sure to get one for a pre '66 trans as it will have two holes and the later ones have only one hole as they have no rear pump. This process has always worked well for me.

I have a couple more questions.

I am having trouble finding the transmission at the local part houses. Does anyone have a part number and brand name for a 1962 727 filter?

Does the torque converter have a plug?

 

[petritl]

I dropped the trans pan and looked at the detent ball and rooster comb...it did appear to be just a little bit off. I set the cable and had all the buttons pushed several times and all of them now seem to stop in the middle of the detents.
A filter couldn't be found but what was on the car was a brass screen which didn't look bad so I cleaned it out well with brake clean and shop air and reused it.

The radiator is out getting cleaned so when it gets back I will be able to test the cable adjustment and see if my problem went away.

 

[SUPERSTOCKRACER]

I dropped the trans pan and looked at the detent ball and rooster comb...it did appear to be just a little bit off. I set the cable and had all the buttons pushed several times and all of them now seem to stop in the middle of the detents.
A filter couldn't be found but what was on the car was a brass screen which didn't look bad so I cleaned it out well with brake clean and shop air and reused it.

The radiator is out getting cleaned so when it gets back I will be able to test the cable adjustment and see if my problem went away.

make sure you push all buttons and always go back to nuetral!
make sure detent is right in the center of the nuetral safety switch.when you go to nuetral on the push button. very important otherwise you'll burn up the trans. fast.
the brass screen is the best one, keep that one.;)

 

[enzo321]

Unfortunately that thread has no solution to the problem, have exactly the same on my 64 440 trans, did adjust the cable diligent but no improvment. Did adjust the kickdown band as well, has anybody an idea?

Thanks

 

[petritl]

Unfortunately that thread has no solution to the problem, have exactly the same on my 64 440 trans, did adjust the cable diligent but no improvment. Did adjust the kickdown band as well, has anybody an idea?

Thanks

The final fix for my transmission was a rebuild. I believe the root cause was a broken sprague.