Trans TH 350 not engaging 1972 cutlass

Thread Tools
 
Search this Thread
 
Old Jun 22, 2020 | 07:56 PM
  #1  
Oldssupreme's Avatar
Thread Starter
Chris
 
Joined: Jul 2011
Posts: 1,287
From: Southern New Jersey
Trans TH 350 not engaging 1972 cutlass

Hi everyone! As I posted in a previous thread this past fall, I installed my transmission back into my car along with the engine. I didn’t know work in the transmission other than to replace the rear seal. I filled the torque converter with fluid before installing it onto the trans, and when filling The trans, I was able to get about 4 quarts in before it started overflowing all over the garage floor following a big gurgling sound. Keep in mind that the engine had not been started, so I was not able to get a true reading on the level. I drain some out until it was halfway between the low and full Mark on the trans dipstick. That was this item. Today I went out and was able to start the engine after replacing the points. However, the transmission would not engage in any gear even though I went through all the gears with the selector as the engine was running. I then checked the trans fluid level, and it was at the very very bottom of the dipstick. I was planning on dropping the pan anyway, to install a new pan with a drain plug, when I did this, there is only a small amount of trans fluid in the pan, maybe half an inch deep, on a stock Pan. I am assuming that the trans fluid was pulled into the transmission and some air work at self out that was there??? I installed a new pan, add about another 3 1/2 quarts, started the engine again, went through the gears expecting it to engage, and it did not. Checked level again and it was down at the bottom of the stick. Added another pint and started the car up again, went through the gears, and felt a barely perceivable movement backwards in reverse and likewise forward in Dr.. Do I need to add more fluid? Work more air out of the system? Am I on the right track? The trans worked with no problem before I took it out of the car. Thank you! Chris
Old Jun 22, 2020 | 08:01 PM
  #2  
Fun71's Avatar
Registered User
 
Joined: Feb 2013
Posts: 15,394
From: Phoenix, AZ
You need to add fluid until the level on the stick registers FULL. If the torque converter drained when you had the transmission out, it may take 10-12 quarts to bring it up to FULL. The TH350 fluid capacity with a stock pan is 11 quarts.

Last edited by Fun71; Jun 22, 2020 at 08:05 PM.
Old Jun 22, 2020 | 08:34 PM
  #3  
Vintage Chief's Avatar
Running On Empty
 
Joined: Jul 2018
Posts: 25,789
From: Earth
The oil needs to be at the FULL mark when the engine reaches normal operating temperature (180°F). Normal operating temperature is generally achieved with ~15 miles of expressway driving. Since you cannot drive the vehicle (yet) you'll need to allow the engine to idle at least 15' to 20' before it reaches normal operating temperature. When at room temperature (70°F), the dipstick should read 3/4" below the ADD mark. Therefore, don't expect to read FULL until the engine reaches normal operating temperature.
Old Jun 23, 2020 | 04:21 AM
  #4  
Oldssupreme's Avatar
Thread Starter
Chris
 
Joined: Jul 2011
Posts: 1,287
From: Southern New Jersey
Hello gentlemen! Thank you for your replies! Yes according to the chassis manual at room temp the fluid should read 3/4” below the “full” mark on the stick. On my stick, that puts it right about at the “add 1 pint” mark. So you are both thinking that because of having the trans and torque converter out and drained that I most likely still am not anywhere near the amount it needs? Thank you!
Old Jun 23, 2020 | 04:25 AM
  #5  
Oldssupreme's Avatar
Thread Starter
Chris
 
Joined: Jul 2011
Posts: 1,287
From: Southern New Jersey
Vintage chief- I reread your post and I guess in misread my chassis manual. You said room temperature reading of 3/4” below ADD mark. I was reading it from below full mark. Either way you think I need more? I thought there would have been more left on the trans and converter but maybe I did a better job than I thought of draining it when it was out of the car.
Old Jun 23, 2020 | 05:15 AM
  #6  
matt69olds's Avatar
Registered User
 
Joined: Jan 2010
Posts: 6,095
From: central Indiana
The engine has to be running for the fluid level to be checked. If the converter/trans was empty when you started it with the 4 quarts you poured in, the converter is about halfway filled up. As mentioned before, a TH350 holds about 11 quarts after a complete overhaul.
Old Jun 23, 2020 | 05:16 AM
  #7  
Vintage Chief's Avatar
Running On Empty
 
Joined: Jul 2018
Posts: 25,789
From: Earth
Originally Posted by Oldssupreme
Vintage chief- I reread your post and I guess in misread my chassis manual. You said room temperature reading of 3/4” below ADD mark. I was reading it from below full mark. Either way you think I need more? I thought there would have been more left on the trans and converter but maybe I did a better job than I thought of draining it when it was out of the car.
Chris -
When at room temperature (70°F), the dipstick should read 3/4" below the ADD mark.
Re-read the CSM the information I provided should be the same.


Old Jun 23, 2020 | 05:20 AM
  #8  
Vintage Chief's Avatar
Running On Empty
 
Joined: Jul 2018
Posts: 25,789
From: Earth
Just so we're clear regarding filling the converter. Note in the 1st post
I filled the torque converter with fluid before installing it onto the trans
Old Jun 23, 2020 | 05:23 AM
  #9  
Vintage Chief's Avatar
Running On Empty
 
Joined: Jul 2018
Posts: 25,789
From: Earth
Reading directly from the CSM CAPACITIES chart:
TRANSMISSION AUTOMATIC Turbo Hydra-Matic 350, Units = Quarts (U.S. Measure) = 10 (quarts)
Old Jun 23, 2020 | 05:42 AM
  #10  
Vintage Chief's Avatar
Running On Empty
 
Joined: Jul 2018
Posts: 25,789
From: Earth
Allow the vehicle to run for a minimum of 20 minutes @ idle approximately sufficient time to reach normal engine temperature. With the engine continually "running" (do not turn the engine off) check the transmission fluid level and fill to the ADD mark. Continually shift through all of the gears as the engine is warming up and while the engine is at a continual normal operating temperature (do not turn the engine off).
You most likely have one or two voids (residual air pockets) in the fluid channels. The transmission needs to achieve a minimum operating pressure and the operating pressure is best achieved when the transmission is warm. You removed the entire transmission, what was left inside the entire transmission was air. Filling the system with fluid within a "static" (non-moving) environment may take a little time for the pressure to build and evacuate all of the air. Be patient. With the engine at normal operating temperature, run the transmission through all of the gears, in particular reverse - numerous times while the vehicle is continually running. Then continually re-check your transmission level after running through the shifting and adding more and more transmission fluid until you reach the FULL mark.
Old Jun 24, 2020 | 10:11 AM
  #11  
matt69olds's Avatar
Registered User
 
Joined: Jan 2010
Posts: 6,095
From: central Indiana
Your not going to be able to fill a converter by just pouring in fluid, at least not easily, quickly, or throughly. Too many places to trap air.
Old Jun 24, 2020 | 10:16 AM
  #12  
Vintage Chief's Avatar
Running On Empty
 
Joined: Jul 2018
Posts: 25,789
From: Earth
Originally Posted by matt69olds
Your not going to be able to fill a converter by just pouring in fluid, at least not easily, quickly, or throughly. Too many places to trap air.
That's right...additionally, you need to attach the flex plate to the converter otherwise no amount of transmission fluid is going to move that car.
Old Jun 28, 2020 | 06:04 AM
  #13  
Vintage Chief's Avatar
Running On Empty
 
Joined: Jul 2018
Posts: 25,789
From: Earth
Chris - I hope you got it rolling.
Old Jun 28, 2020 | 06:29 AM
  #14  
Oldssupreme's Avatar
Thread Starter
Chris
 
Joined: Jul 2011
Posts: 1,287
From: Southern New Jersey
Hi! Thank you for asking! I haven’t had a chance to get back to work on the car- but tomorrow will be the day. I’m going to get the fuel delivery situation figured out, then once I can keep it running on it’s own I’ll work out the trans issue and then adjust the gas tank to fit correctly and fill that up... then I’ll reveled the brakes and chase a small leak in the connections of the new lines above the rear end... thanks to all who have helped!! Much appreciated!
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Oldssupreme
Transmission
5
Aug 31, 2019 10:16 PM
Perkolator
Transmission
3
Apr 13, 2017 06:37 PM
truckman5000
Transmission
4
Jul 16, 2016 07:20 PM
coppercutlass
Transmission
8
Jun 30, 2013 11:42 AM
DAN76
Transmission
9
Mar 25, 2009 08:26 AM




All times are GMT -7. The time now is 04:32 AM.