Frame Spread, Hi Head Low head and Off-center Hoses

Frame Spread

Model T frames, like people, tend to sag a little in the middle over time. The weight concentrated in the center of a T’s frame may cause the front crossmember to sag and cause the frame rails to spread resulting in center-to-center growth of 1/4 ”-1/2”

The center-to-center distance of the mounting holes in the frame of a Model T rolling off the factory line is 21-1/2”. Model T owners should ALWAYS check the center-to-center frame hole mounting distance before locating and installing a new Brassworks radiator on the frame as the frame may spread as much as 1/8" or more.

A common procedure to correct “frame spread”;

  1. Apply three equal pressure points on the frame rails sides
  2. Retain the front cross member in position
  3. Crank the bottle jack upward on the chain which will push the front cross member down while pulling the frame rail sides in.
  4. When the distance between the two radiator mounting holes is 21-1/2", then you have corrected the frame spread.

Please note that simply pulling on the frame rails sides and not retaining the crossmember may only cave in the sides of the frame and leave the crossmember uncorrected and the problem unresolved.

 Hi Head vs Low Head

If you experience a water neck to radiator inlet hose connection alignment, first confirm the correct head has been installed in your engine.  Prior to 1913 the low head were used before 1913 and later the high head was standard.  Bolt holes on a low head are 2-1/8", on a high head they're 2 - 5/8".

Hi low

Off-center Hoses

If you look at your new model t radiator and think that the upper hose is not centered then you are right.  It is supposed to be that way to align with the engine.