Hello everyone. I had a perfectly good shifting Hydra-Matic transmission until I elected to fix the leak at the dip stick tube. I just did a quick seal with gasket maker since my current tube is missing the mount and I was headed to the Lead Sled show in Salina, KS in a few days. I drained about 2 quarts of fluid so I could do a good cleaning around the inlet and under the dirt flange of the tube. Installed gasket maker and reinserted the tube then let it sit for 24 hours. Topped off the fluid level the next night and took it for a test drive and now I only have park, 1st gear and neutral only. I have run the diagnosis in the manual. Reverse table is normal, low table is normal, third table has no 2nd, third or fourth, same results for fourth table per the manual and neutral table is normal. I would think I could assume no broken parts and this is a result of possibly stirring up debris from refilling the transmission. If so if I get into the valve body will I need new seals or is it a take apart clean and reassemble process? Could the governor be suspect and if so should I start there?

On the bright side I did stop the leak.



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Did you check your trans fluid level with the car running —at operating temp ?

These trans will not shift right if trans fluid is low 

The dip stick is marked in pints 

See no reason the trans should be shifting any different than before from the repair  work you did 


Yes got the everything up to temp and checked level it was a about half a pint low. I left it running and added to the full mark. Still nothing above 1st gear. 

The TV Rod on the carb of a 63 controls the  trans shift points 

Just be sure all looks as it should on the carbs linkage in that location ( nothing loose or falling off ) 

Just some basics that come to mind 


Only think I can figure is that debris fell into the trans and settled into the governor.  

Russ I believe you are right. I went back out and ran the diagnostic tables and came up with a condition 2-9602 which is an 11 on diagnosis index chart. See attached chart which would lead me to believe it is the governor. I'm waiting on the delivery of the extension to rear pump gasket to clean the governor. It does mention the G1 governor valve stuck but I’m not positive we’re that is located. My guess it is located in the valve body?



G1 valve they refer to is in the governor assembly, i believe.  It is the valve that opens and closes when the weights move.

I thought that as well except that valve is called G2 on the exploded view in the manual. I can't find any mention in any exploded views of a G1 valve. There is a G1 passage in Fig 6-6 transmission case oil passages.


G1 is a passage that could be obstructed  — as of item d on the  bottom of the chart you posted - so not a valve 



Thanks for the reply, so there isn’t a G1 valve as stated in item (a) “G1 valve stuck closed”?

Thanks for your continued help, I just want to tear it apart once. 

I think it should read —G1 passage valve is stuck closed 

I think we just corrected the Service Manual on the subject


Unfortunately, by the 63 model year, the Hydramatic's days were numbered, and the theory of operation info in the shop manual is quite sparse.  There are just perfunctory images and no hydraulic flow diagrams at all.  I guess by 63 the techs were old hands at it, and they would refer to earlier books in a pinch rather than reprinting the same info year after year.   

The G1 valve is what the manual shows as the G1 weight.  It's a non-removeable(?) part of the governor in the last years, so they didn't see fit to include it in the diagram.  If it can't be freed up, the governor must be replaced, but I think soaking in denatured alcohol should probably cure it.  If it's free moving, then you'll need to drop the valve body to check out the passages for a glob of RTV.  

The governor controls two pressures, G1 and G2.  G1 is a large weight and begins to open as soon as the car begins moving, and gains pressure in accordance with speed.  G2 is the smaller weight, and is fed directly by G1 pressure, so if G1 is stuck, they are both stuck.  G2 only opens at higher speeds.  

from an earlier transmission book:

Section A Jetaway / A-Jetaway0043.jpg

Mark, Russ and Tony

Thank you for your reply’s and the willingness to help a new Series 62 owner. I.m learning this sight is invaluable to the owners of theses cars. I know my way around a wrench but am a bit nervous about tearing into an automatic transmission. Given the fact the previous owner had copious amounts of RTV on the trans filler tube, conservatively speaking a full inch on the tube and into the transmission case, should I start at the valve body?

Thanks again!



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