The Ford Barn

Bill Lee/Virginia · 06-03-2015, 08:09 PM

Since the opening at the front of the Model A engine at the first oil dam in the valve chamber dispenses oil down upon the timing gear and the crank gear and additional oil into the engine pan, What is the purpose of the oil return pipe?

Charles Coe · 06-03-2015, 09:56 PM

To return any excess oil to the oil pan.

Benson · 06-03-2015, 11:15 PM

Helps to keep the dipper tray full for the rod bearings.

Also keeps the oil level in rear of the valve chamber from getting too high ... reduces oil being sucked up valve guides in rear of engine.

That is why the oil return tube was lowered ... to lower oil level and to reduce oil consumption .

BRENT in 10-uh-C · 06-04-2015, 09:44 AM

Quote:

Originally Posted by Benson

Helps to keep the dipper tray full for the rod bearings.

Also keeps the oil level in rear of the valve chamber from getting too high ... reduces oil being sucked up valve guides in rear of engine.

That is why the oil return tube was lowered ... to lower oil level and to reduce oil consumption .

Have you ever really thought about how high the oil level would need to be back there to actually have it 'sucked' up into a valve guide. I suppose it is possible if someone were driving up a 45 degree incline it would reach the #4 guides, but how long would the car actually traverse an incline like that where it would/could even be an issue. I will admit that Henry's boys tried to delete that return pipe and then re-installed it for some reason, --so evidently they felt it was needed.

Benson · 06-05-2015, 10:01 AM

Quote:

Originally Posted by BRENT in 10-uh-C

Have you ever really thought about how high the oil level would need to be back there to actually have it 'sucked' up into a valve guide. I suppose it is possible if someone were driving up a 45 degree incline it would reach the #4 guides, but how long would the car actually traverse an incline like that where it would/could even be an issue. I will admit that Henry's boys tried to delete that return pipe and then re-installed it for some reason, --so evidently they felt it was needed.

Maybe the oil can not be sucked up the valve guides but the oil was going somewhere.

All I know is that in May of 1929 Ford Engineers thought lowering the drain tube would reduce oil consumption.

From Service bulletin page 342:

"This change lowers the oil level in the valve chamber; prevents any possibility of oil being thrown up around the valve springs and reduces oil consumption"

katy · 06-05-2015, 11:14 AM

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Newbie here, I owned and drove Model A's back in the 50's. Am in the process of buying a '31 pickup and then bringing it back to Alberta from the US.
Question: I have heard that the oil tubes come in 2 different lengths, is this correct? If so, when was the change made? And any idea why?
TIA, Ken

Tom Wesenberg · 06-05-2015, 12:45 PM

The change in length was at the same time the pipe was lowered. You'd think the lower pipe would be a bit shorter, but it's actually the longer one.

The engine sets at an angle with the rear the lowest, so having a drain pipe at the rear to feed oil to the higher front end of the dipper tray seems like a good reason. When climbing a hill this is even more important.

Will N · 06-05-2015, 01:39 PM

I believe the external return pipe also serves to cool the oil somewhat.

06-03-2015, 08:09 PM	#1
Bill Lee/Virginia Senior Member Join Date: May 2010 Posts: 295	Oil Return Pipe Question Since the opening at the front of the Model A engine at the first oil dam in the valve chamber dispenses oil down upon the timing gear and the crank gear and additional oil into the engine pan, What is the purpose of the oil return pipe?

06-03-2015, 09:56 PM	#2
Charles Coe Senior Member Join Date: May 2010 Location: Pace, FL near Pensacola Posts: 374	Re: Oil Return Pipe Question To return any excess oil to the oil pan.

06-03-2015, 11:15 PM	#3
Benson Senior Member Join Date: May 2010 Posts: 2,599	Re: Oil Return Pipe Question Helps to keep the dipper tray full for the rod bearings. Also keeps the oil level in rear of the valve chamber from getting too high ... reduces oil being sucked up valve guides in rear of engine. That is why the oil return tube was lowered ... to lower oil level and to reduce oil consumption . Last edited by Benson; 06-03-2015 at 11:25 PM.

06-05-2015, 11:14 AM	#6
katy Senior Member Join Date: Jun 2015 Location: Red Deer, Alberta Posts: 5,046	Re: Oil Return Pipe Question Sponsored Links (Register now to hide all advertisements) Newbie here, I owned and drove Model A's back in the 50's. Am in the process of buying a '31 pickup and then bringing it back to Alberta from the US. Question: I have heard that the oil tubes come in 2 different lengths, is this correct? If so, when was the change made? And any idea why? TIA, Ken

06-05-2015, 12:45 PM	#7
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Re: Oil Return Pipe Question The change in length was at the same time the pipe was lowered. You'd think the lower pipe would be a bit shorter, but it's actually the longer one. The engine sets at an angle with the rear the lowest, so having a drain pipe at the rear to feed oil to the higher front end of the dipper tray seems like a good reason. When climbing a hill this is even more important.

06-05-2015, 01:39 PM	#8
Will N Senior Member Join Date: Jul 2010 Location: Pennsylvania Posts: 1,100	Re: Oil Return Pipe Question I believe the external return pipe also serves to cool the oil somewhat.