oil flow in an 8BA

Here is a link to a PDF of the Canadian/military flathead showing the full flow setup that was used in the military versions and I guess as an option in later Canadian vehicles. It will give you something to study to learn the oiling system of the flathead, although the usual filter arrangement is a bypass system that dosen't use the special fitting in the military version.
http://www.jalopyjournal.com/forum/attachment.php?attachmentid=823076&d=1258957689

The normal bypass filter connects to the fittings on the back of the block that also connect to the input of the oil pressure sending unit; and the out put of the filter plumbs into the oil pan. There is a restrictor in the fitting to the filter that limits the flow into the canister.
 
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That is the standard flathead diagram in that older thread linked on the previous post 3. Oil feeds the rear main first then feeds valve chamber passage with a Y for filter. All of the cam & front two main bearings are fed from the valve chamber tube. The oil filter has a restrictor to provide control of overall system pressure then after the filter, it just drains back to the oil pan as in the wonderful pictures on that thread.

Kerby
 
No, all of the cam bearings are not fed from the valve chamber tube. The rear cam bearing is supplied oil from the oilpump drive gear case at the rear of the block.
 
I'm not as familiar with the engines prior to the 8BA so the oiling system may be a little different. I do know the 8BA has pressure feed to the fuel pump push rod that also leaks down into the rear cam bearing area. Since the eccentric is between the two rear cam bearing journals, it helps lube them both plus the splash oil from the oil pump drive and idler gears. That is why I don't eliminate the valley tube pressure from the equation. The rear cam bearings are not directly pressure lubed in the 8BA but they do have more than one pressure lube source. The source from the top of the pump to the gear compartment is also from leak by around the top of the oil pump body.

I'm sure they did this to keep oil pressure under control but still get everything lubed well.

Kerby
 
Hello, even though this thread is quite old, At the beginning there was a link to a PDF of the Canadian/French/military flathead oil flowing/showing. Unfortunately, it no longer works. Does anyone else have this PDF?
 
I would like to know where the oil lines are in my French V8 Flathead.
How the oil circuit works.
 
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