727 Torqueflight question

Kevin Panzino · 06-28-2020, 02:07 PM

Gents, I have no experience with a 727 transmission.
I have a 1974 IH Scout II with that trans.
If the scout sits for even a few days the converter drains back into the trans overfills it, then leaks on the floor.

Is there a check ball or some other means in the valve body that is supposed to prevent this? It did not do this until recently.

Kevin Panzino

ss3011 · 06-28-2020, 06:02 PM

Where is it leaking from , the pan gasket or dipstick tube ? Best to fix those leaks , not much you are going to do to solve converter draindown .

Myron Piatek · 06-28-2020, 06:49 PM

Also check the case seal where the shift lever attaches to the valve body on the driver's side.

e vassar · 06-29-2020, 03:16 AM

Had 727,s in a couple bracket cars. If i filled them to the exact full mark on the stick, they would leak down to their happy spot. Probably about 1/4 quart then stop. So i finally quit filling them back to the full mark and they would stay right there.

Kevin Panzino · 06-29-2020, 07:57 AM

Ok, I see. It probably always drained back to the trans, just now what has changed is that its leaking. I changed the pan gasket, no love. Hard to see where its coming from because it just runs along the pan rails and drips from the pan bolts.

Gonna take a close look at the dipstick tube seal, and the shifter linkage seal now.

Thank you all for the input !!!

Kp

Jack Zimmerman · 06-29-2020, 11:01 AM

If the dipstick is the 1974 style there is an o-ring on the bottom where it inserts into the transmission unlike the push-in seals that they use today and I've had those o-rings get hard and leak. So the best fix for that is to get a new style seal and dipstick but unfortunately I don't know the part numbers for what you need but maybe someone else knows.

Cotten · 06-29-2020, 12:28 PM

Also look at the neutral safety switch, on drivers side above pan rail. They get old and crack and leak down onto pan rail. It looks like its the pan gasket leaking.

GTX JOHN · 06-29-2020, 01:52 PM

Most common leak and most difficult to find is dipstick tube.
The new ones are a way better sealing arraignment. But a new O ring from
the hardware store and making sure it is not bent up will usually save
the day!

theman440 · 06-29-2020, 03:43 PM

More than likely the culprit is the selector shaft seal.

Kevin Panzino · 06-29-2020, 08:44 PM

Thanks guys. Gonna get it up on the lift and take a closer look.

06-28-2020, 02:07 PM	#1
Kevin Panzino Senior Member Join Date: Oct 2002 Location: Pittsburgh Posts: 575 Likes: 298 Liked 747 Times in 136 Posts	727 Torqueflight question Gents, I have no experience with a 727 transmission. I have a 1974 IH Scout II with that trans. If the scout sits for even a few days the converter drains back into the trans overfills it, then leaks on the floor. Is there a check ball or some other means in the valve body that is supposed to prevent this? It did not do this until recently. Kevin Panzino

06-28-2020, 06:02 PM	#2
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 909 Likes: 70 Liked 239 Times in 114 Posts	Re: 727 Torqueflight question Where is it leaking from , the pan gasket or dipstick tube ? Best to fix those leaks , not much you are going to do to solve converter draindown .

06-28-2020, 06:49 PM	#3
Myron Piatek VIP Member Join Date: Nov 2001 Location: Florida Posts: 1,542 Likes: 34 Liked 138 Times in 51 Posts	Re: 727 Torqueflight question Also check the case seal where the shift lever attaches to the valve body on the driver's side. __________________ LOCOMOTION Racing

06-29-2020, 03:16 AM	#4
e vassar Member Join Date: Jul 2015 Posts: 380 Likes: 67 Liked 271 Times in 107 Posts	Re: 727 Torqueflight question Had 727,s in a couple bracket cars. If i filled them to the exact full mark on the stick, they would leak down to their happy spot. Probably about 1/4 quart then stop. So i finally quit filling them back to the full mark and they would stay right there.

06-29-2020, 07:57 AM	#5
Kevin Panzino Senior Member Join Date: Oct 2002 Location: Pittsburgh Posts: 575 Likes: 298 Liked 747 Times in 136 Posts	Re: 727 Torqueflight question Ok, I see. It probably always drained back to the trans, just now what has changed is that its leaking. I changed the pan gasket, no love. Hard to see where its coming from because it just runs along the pan rails and drips from the pan bolts. Gonna take a close look at the dipstick tube seal, and the shifter linkage seal now. Thank you all for the input !!! Kp

06-29-2020, 11:01 AM	#6
Jack Zimmerman Junior Member Join Date: Dec 2001 Location: Clemmons, NC Posts: 35 Likes: 0 Liked 11 Times in 6 Posts	Re: 727 Torqueflight question If the dipstick is the 1974 style there is an o-ring on the bottom where it inserts into the transmission unlike the push-in seals that they use today and I've had those o-rings get hard and leak. So the best fix for that is to get a new style seal and dipstick but unfortunately I don't know the part numbers for what you need but maybe someone else knows.

06-29-2020, 12:28 PM	#7
Cotten Member Join Date: Aug 2007 Posts: 234 Likes: 484 Liked 556 Times in 69 Posts	Re: 727 Torqueflight question Also look at the neutral safety switch, on drivers side above pan rail. They get old and crack and leak down onto pan rail. It looks like its the pan gasket leaking.

06-29-2020, 01:52 PM	#8
GTX JOHN VIP Member Join Date: Jun 2009 Location: Boulder City, Nevada 89005 Posts: 2,731 Likes: 2,794 Liked 2,471 Times in 696 Posts	Re: 727 Torqueflight question Most common leak and most difficult to find is dipstick tube. The new ones are a way better sealing arraignment. But a new O ring from the hardware store and making sure it is not bent up will usually save the day! __________________ John Irving 741 Stock 741 Super Stock Last edited by GTX JOHN; 06-30-2020 at 04:40 AM.

06-29-2020, 03:43 PM	#9
theman440 Member Join Date: Apr 2013 Location: Fabulous Las Vegas Posts: 114 Likes: 29 Liked 24 Times in 13 Posts	Re: 727 Torqueflight question More than likely the culprit is the selector shaft seal. __________________ Jeff Dudgeon '66 Coronet #10771 - bracket puke "the Flying Brick"

06-29-2020, 08:44 PM	#10
Kevin Panzino Senior Member Join Date: Oct 2002 Location: Pittsburgh Posts: 575 Likes: 298 Liked 747 Times in 136 Posts	Re: 727 Torqueflight question Thanks guys. Gonna get it up on the lift and take a closer look.