Transmission and Differential oil

[29hupp]

I am in the countless hours job of restoring my 1929 Hupp Sedan.  The below thread reminded me that I need to ask.  What weight oil should I use in the transmission and differential?

[Hupp36]

One  of the  Hupmobile  manuals I  have  says  70  weight gear oil in the  summer ,  50  wight in the  winter. I  have  a number  of  old  cars  and  w-80-90 works  well. I  would  not  use a  synthetic as most of  the  early  seals  do  not  like  it.   

[29hupp]

Thanks!

[Hupp36]

How  about  a pic of  you  Hupp?

[29hupp]

Bought the car over 50 years ago with intention of restoring.  Disassembled much of the car.  Draft notice  from Uncle Sam required the next 2 years of my life.  Got married, had kids and life took over with the Hupmobile stored in 3 garages.  Retired 4 years ago and  I am picking up where I left off on the restoration now  at 71.   I am on a tight budget so I plan to do everything I can myself.  Started the engine  for the first time last week  and it sounds great.  Attached are a few pictures. 

[Hupp36]

Looking good on the  side  water  jacket  plate, I  caution you  not to  use a flat plate of  metal. The  original one  is  embossed for better  cooling.The  1929 Hupp model  A  which your  car is and the one I  just  restored I had  a heating  problem. The radiator  is  honey combed. It  can not  be rodded out  like the  1930 Model S  that  has straight  tubes. I  had the radiator boiled  out  and that  helped quite a bit, but  what  really cooled it  down  was the pitch on the  fan.  Before  I  changed the  fan, I  set an  electric fan on a chair  and introduced more  air  to the radiator. The  temperature gauge  stayed at 170 Deg. The  temperature  outside was 90 to 95. I  removed  the  fans off  both cars. In matching them  up,  the  1931 Model  S  fan  had  a more aggressive pitch. After changing the  fans , problem  solved. I  then  sold the  car as  I  knew it  would be  ok  for the  new  owner.  Hopes  this  helps  and  if  you  have  a  question,  if  I  can  not  answer it, I  know other  Hupp technical advisors  that  can. 

[29hupp]

Thanks that is good information.  I do have the plate though.  I had to make a rear main seal holder which is shown in the previous picture in my lathe.  I melted aluminum cans to use for the casting and bolted two of them together to cut the grove for the seal.   

[Fordy]

I probably have to make that casting for the rear main seal. I pulled down a sad 1929 motor today and that thing just crumbled. Enough to make a pattern though. Didn't even think about casting a pair and cutting the groove like you did - great idea!