Bypass oil filter restrictor fitting

C

chiro

Senior Member
Anybody have a source for this fitting and the "T" fitting that accepts both it and the oil pressure sending line for the flathead V8?

Thanks,

Andy
 
Stock restrictor was more like .060 I believe. You can make one by soldering/brazing up a fitting and drilling the hole. Doubt the .093 vs .060 would make much difference in engine oil pressure.
 
"When using the stock flathead oil filter system, it is important to retain an oil restrictor at the inlet to the filter canister. The fittings pictured incorporate a .060” (approximately) diameter restrictor hole to prevent too much flow through the filter, particularly if the filter element is not installed (ouch!). The Eaton/Weatherhead catalog still shows a similar replacement part available under catalog number 1512. The 1951-1953 Ford engines and the 1949-1953 Mercury engines incorporated the restrictor into a “T” fitting that also mounted the oil pressure sending unit. The part numbers are 8CM-6073 for the Mercury and 1BA-6073 for the Ford ."

Oil inlet restrictor for all T3, T3/T4, T04, T72 etc. turbos (also larger ball bearing turbos such as GT4088R, GT4094R, GT4294R, GT4202R). Restrictor diameter of .065 hole size. Installed at the oil inlet on turbo to reduce max oil pressure going into the turbo to prevent oil leakage into end housings due to excessive pressure. Input is 1/8" NPT male and output is 1/8 NPT female.

Looks like most of the current restrictors are for turbo changes, but won't make any difference, a restrictor is a restrictor. I think there is one specific for the flathead filter but haven't found it yet.
 
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At typical Mercury restrictor fitting.
 

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If you have a stock oil filter canister there is a restrictor hole in the stand pipe. Nothing more is needed. JMO
John
 
An option when using the Ford or Mercury "T" fitting, with restricter, is to put the sending unit at the rear of the engine, (as '50 and earlier), and put an oil pressure gauge in the "T" fitting. JM2CW,
Howard
 
oldford2 said:
If you have a stock oil filter canister there is a restrictor hole in the stand pipe. Nothing more is needed. JMO
John
Click to expand...

What are you referring to as a "stand pipe"? The restrictors are either at the fitting at the rear of the block or at the inlet to the filter canister. The canister itself does not have a restrictor in it.
 
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It does, the center standpipe has a small hole in it that oil returns to the pan thru. Without a restrictor on the inlet, tho, you'd have a rush of oil refilling the filter on start-up, robbing the engine, not real desirable. But once you're up and running, the hole in the standpipe would suffice.
 
Unless I'm missing something it was my understanding the the return holes were much larger than the restrictor and I thought there were two of them. Not sure where the idea that these bleed back holes were restrictors came from!

The inlet area is .0028 and the outlet area is .0062. The outlet is approximately double the inlet size to keep the pressure down in the canister. I would assume that the Ford engineers knew what they were doing and didn't add extra parts and expense that weren't needed.

Note: Canister photo is borrowed from a 51 MERC-CT post.
 

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Jseery is correct,
There are two holes in the stand pipe, these holes combined have twice the area than the one restrictor hole on the oil in line. For the filter to work as intended, it needs the restrictor on the oil in line. The two holes in the stand pipe do not restrict the flow enough.
Martin.
 
Hey thanks for all the replies, mostly information that I already know. So...the original question was who has a source for these items? The Napa/Weatherhead fitting is not available from Napa (comes up as being out of stock).

Anybody have a source?

Thanks,

Andy
 
In addition to the restrictor in the oil filter standpipe. Inside our 46 oil pan the return line adapter also has a restrictor. I think the thought that on startup the engine is "robbed" of oil while the filter is filling up is a myth. Oil pressure at startup does not indicate any drop in pressure.
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John
 
I made mine. I took a standard "T" fitting, applied flux to a brass bolt and screwed it in, sweated and soldered it, cut off the bolt head, then drilled a .055" hole through it. The hardest part was drilling the hole-use a drill press, go slow, use lots of oil.

Took me about 15 minutes and works perfectly.
 
JSeery said:
Stock restrictor was more like .060 I believe. You can make one by soldering/brazing up a fitting and drilling the hole. Doubt the .093 vs .060 would make much difference in engine oil pressure.
Click to expand...

You are 100% correct. The specification was .060" - .063" as I recall. I have, when necessary, soldered up a fitting and drilled to suit just as you'd advised.
 
materguru said:
you wouldnt know the part# to the T fitting for the oil filter that you pictured in this thread?
Click to expand...
The 'T' fitting pictured (PN 8CM-6073A) is specific to '49-'51 Mercury.
Ford and later '52-'53 Mercury used a different design fitting.
The largest drill that the hole will accept is a #54 (.055" dia.) actual measurement and not from anecdotal information.

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