F Motor is a Better Oiler

Steamer

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The F manual offers no diagram of how the regulator is plumbed. It only offers a description of it. I believe I correctly hand drew how it is plumbed going from the manual’s description paying attention to the one sentence I boxed in red above.

If I interpreted and drew it correctly then either the manual or Redline is incorrect.

The F manual’s description does not match the Redline diagram.
 

middlecalf

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On the right side of the cross-section of the regulator in the F-manual you can see where the oil flows through it to the hose connection that goes to the oil filter. When the pressure of that flow exceeds the spring force it pushes the oil into the left chamber (ambient pressure) which drains to the oil pan.
319BCCFD-71FE-45C6-9E56-DF6E3AEDF8AF.jpeg


I use a magnetic heater on my oil pan at home in really cold weather to help with startup oil circulation.
 

middlecalf

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I haven’t been able to find anywhere where the oil pressure sending unit is getting it’s reading from. I didn’t look closely when I had my motor apart to see where the probe goes, but the sending unit is mounted on the side of the block toward the firewall from the oil regulator regulator. If it’s measuring the block pressure, or what I call the ambient pressure in the above post, then being fixed in volume the pressure should go up as the motor warms up, but it instead drops. It doesn‘t directly connect to the oil pump or the oil filter (at least the feed line). Maybe the oil filter return line port and the pressure sending unit share a common block galley so it’s measuring the output side of the filter? But since that drains into the oil pan then it would in essence be measuring the ambient block pressure. And in that system there’s the PCV subsystem as well (at least optional for US market). 😂

FWIW the mechanical measuring oil pressure unit on my SBC 283 is reading from the top of the block back by the distributor.
 
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If it’s measuring the block pressure, or what I call the ambient pressure in the above post, then being fixed in volume the pressure should go up as the motor warms up, but it instead drops.
Maybe the pressure drops because the sending unit is closer to the oil pump, and oil is finally going thru the small paths in the now warm motor - there is less back-pressure and it is reflected on the dash. Also, the oil filter assembly is warm, so oil passes thru that branch easier.

On a 2F the pressure goes up when it gets warm, because it can finally go thru the small holes in the filter element on the screw-on-filter-assembly, which is less effort needed than to go thru the internal bypass valve (cold or rpm/racing). I'd imagine that the pressure would go down, if I deleted the filter element, internally, oil would pass thru a warm engine and there would be less back-pressure to read on the dash.
 

Steamer

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On the right side of the cross-section of the regulator in the F-manual you can see where the oil flows through it to the hose connection that goes to the oil filter. When the pressure of that flow exceeds the spring force it pushes the oil into the left chamber (ambient pressure) which drains to the oil pan.
Ah! Thank you for that. I missed that image and I never saw an F in person. Most of all I didn’t realize that the regulator has three ports. That’s where my confusion was.

Did I label the regulator diagram correctly?

Regulator 2.jpg
 
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The above makes sense to me if the relief valve/regulator is from a top-down view, and the spring is a compression one. The artist seems to have a hard time making a pipe thread female fitting on the right of the drawing.
 

micruz60

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Ok, so which do you believe to be correct?
I believe your hand drawing of how the F manual describes it.
Does an F engine have an oil cooler? Either way, regardless, the engine is being lubricated. It seems the concern lies with how effective or efficient the FILTER performs. Just trying to learn the oil circuit.
Cold starts - makes sense the oil bypasses the restrictive filter media; but could indicate a problem with the relief valve- that is spring loaded.
 

Steamer

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I believe your hand drawing of how the F manual describes it.
Actually, in that drawing I didn’t depict the third port as I wasn’t aware of it. I now realize that schematically the Redline diagram is correct but it’s confusing because it shows the “T” intersection outside of the regulator when in fact it occurs within the regulator.

I think Redline could do a better job on their drawing and depict the “T” intersection within the regulator.

OilCircuit.jpg
 

middlecalf

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@Grayscale I was just talking to a friend after church about this and he says the same thing you said wrt pressure drop as the oil warms up because it can flow into more places more readily, so effectively the volume has increased. He’s been around a few decades 😂.

@Steamer thats I how I see the regulator working FWIW. Good stuff.
 
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@Grayscale I was just talking to a friend after church about this and he says the same thing you said wrt pressure drop as the oil warms up because it can flow into more places more readily, so effectively the volume has increased. He’s been around a few decades 😂.

@Steamer thats I how I see the regulator working FWIW. Good stuff.
Sounds like my kind of congregation. Not that I actually know or have much experience with the ins and outs of these engines.
 

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