NO Oil Return Block History

Roadster62

Roadster62

Well-known member
I did a search and nothing turned up, think I read about a short run of Model A blocks that didn't have an oil tube from the valve chamber to the bottom of the block. I was looking at a Hopped Up A engine from the 1960's that used one of them. A block not a B, were they any better than a standard tube style block than most A's have? Thank you. Bob
 
Roadster62 said:
I did a search and nothing turned up, think I read about a short run of Model A blocks that didn't have an oil tube from the valve chamber to the bottom of the block. I was looking at a Hopped Up A engine from the 1960's that used one of them. A block not a B, were they any better than a standard tube style block than most A's have? Thank you. Bob
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Bob,

Here is just a little history that might help:

http://plucks329s.org/pdf/engineblock/CYLINDER_BLOCK_CHANGE_DESCRIPTION.pdf


Ford discontinued them after about 1355 were built between July and October 1928.
Pluck
 
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Well that's a nice bit of info for the brain
Thank you for the question...And thank you for the answer
 
There was a guy in the classifieds that was looking for a valve cover without the oil return tube a while back. Don't know if he ever found one. I made a couple of suggestions on how to do a work around, but he didn't like those.
 
After abandoning the block design that incorporated oil drainage holes in the floor of the valve chamber, Ford brought it back for the Model B block. I have wondered about the thought process behind this evolution.
 
An abundance of oil needs to get into the dip tray to assure the connecting rod troughs become full. The oil return pipe takes excess oil pump volume and returns it directly to the tray. My guess is that Ford decided it was less complex and thus less expensive to eliminate the oil return pipe by putting drain holes into the bottom of the valve chamber.

However, as the bearing feed holes are also in the bottom of the valve chamber, the oil supply to the bearings becomes uncertain. So Ford went back to the oil return pipe which assures a good oil return without threatening the bearing's oil supply. The oil flow through the return pipe is regulated by the position of drain holes in the valve cover, and size of those holes.
 

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Anyone have a picture of a Model B block showing the drain holes in the bottom of the valve chamber?
 
No pictures as my engine is all buttoned up. My notes from the rebuild show two 11/16 inch holes in the floor of the valve chamber, in the middle of the area between the fore and aft cylinder pairs (1,2 and 3,4) and the adjacent valve guides. the two holes probably flow as much oil as the Model A oil return pipe. Maybe somebody has a photo?
 
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