Model A

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Oil Return Pipe Variations

Shown here are some details of the A-6645 oil return pipe assembly. This pipe returns excess oil in the valve chamber to the crankcase.

Part
Number
Length
center-to-center
Usage Notes
A-6645-R 14-1/2" 1928-29 Model A and AA engines
With high valve cover port
A-6645 15" 1929-31 Model A and AA engines
With low valve cover port

In May 1929 Ford redesigned both the pipe and the valve cover to slightly lower the outlet port on the valve cover to reduce oil consumption.

The valve cover bolt locations required that the new oil return pipe be lengthened slightly to reach the revised oil port location.

The 1929-31 design pipe is about 15 inches long center-to-center and is shown on the top.

The 1928-29 design pipe is about 14-1/2 inches long center-to-center and is shown on the bottom in the pic.

The pic above shows some details of the end caps attachments on the pipe assembly.

The later pipes had end caps which were tack welded to the tube and also were brazed, not soldered.

These improved pipes are very strong and do not leak. The early design end caps were soldered to the pipe and easily crack and leak.

Also seen in this pic is that the gasket surface has a large machined flat area for the gasket to seat, and also the fact that the machining was done on the assembly after the end cap was tack welded.

The outside of these brazed caps also shows the distinct edge around the gasket area. The soldered style end caps have a very washed out radius appearance.


More related information on Ford Garage:

  1. For more Model A & B related information, use the Site Search box at the top or bottom of this page.
  2. Model A & B Valve Cover Variations
  3. Model B Russian GAZ Valve Cover  
  4. Model A & B Timing Gear Side Cover Variations
  5. Model A & B Camshaft Gear Front Timing Cover Differences

April 2002