Oil Filters

dansluck

Senior Member
What type of oil filter works best with the Model A's low oil pressure? I have been using a Motorcraft FL-1A but I believe these were designed for pressures around 40 lbs.
Dan
 
Filters for modern cars have a check valve that prevents drain back. It takes a certain amount of pressure to open the check valve which means that these filters do not work well on Model A's unless you have 45 psi oil pressure. The filters for hydraulic systems do not have the check valves so they are best for Model A's. You can check by trying to blow through the filter. If you can then no check valve. Best to use a rubber hose so that your mouth does not get contaminated by the preservative they put in the filters when they are shipped.
 
Hallo und guten Abend,


after several attempts and measurements I use this filter: 'MANN W-77'

* It is not a fine filter with strong counter pressure.

* It has a non-return valve that prevents the filter empty if the engine is not running.

* It has a by-pass valve if the filter is clogged or cold oil is too thick.

* It is small.
 

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Filters for modern cars have a check valve that prevents drain back. It takes a certain amount of pressure to open the check valve which means that these filters do not work well on Model A's unless you have 45 psi oil pressure. The filters for hydraulic systems do not have the check valves so they are best for Model A's. You can check by trying to blow through the filter. If you can then no check valve. Best to use a rubber hose so that your mouth does not get contaminated by the preservative they put in the filters when they are shipped.

Are you miss taking the anti-back flow valve (check valve) for the bypass valve? The bypass valve is there to prevent overpressure. The anti-back flow valve is there to prevent back flow.

I can open the back-flow valve easily on my WIX 51515 with my finger. basically no resistance, certainly not 45psi.

And yes, a WIX 51515 by-pass valve is set at 45psi.

My oil pressure is running ~6psig. I am sure the gauge would be reading a lot higher if it was trying to overcome 45psi.

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What is wrapped around your filter?

Hallo und guten Abend,


after several attempts and measurements I use this filter: 'MANN W-77'

* It is not a fine filter with strong counter pressure.

* It has a non-return valve that prevents the filter empty if the engine is not running.

* It has a by-pass valve if the filter is clogged or cold oil is too thick.

* It is small.
 
You can check by trying to blow through the filter. If you can then no check valve. Best to use a rubber hose so that your mouth does not get contaminated by the preservative they put in the filters when they are shipped.

It sounds to me you are trying to blow thru the filter backward, thus closing the anti-flow valve.

479600
 

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I have never experienced a anti drain back valve that I could open by blowing in the intake end of the filter. But there may be such an animal, as it seems by other's comments. I am not sure what pressure it takes to open the anti drain back valve but not 45 psi. That was just a number I grabbed out of the air for emphasis.

Regarding what hydraulic filter fits, that would depend on what hardware you are attaching the filter too. Search for hydraulic filter then match the diameters of the outer O ring and inner O ring and the thread. I ended up re threading the housing for my Model T which does not have an oil pump but relies on the flywheel slinging the oil. A fitting on the side of the flywheel housing will produce just enough pressure to flow oil through a hydraulic filter and to a fitting at the nose of the engine.
 
I have never experienced a anti drain back valve that I could open by blowing in the intake end of the filter.

How to you even blow into the inlet of the filter with the 5-6 holes? Are you referring to the threaded hole, which is the outlet? Please see diagram above.
 
The anti drain valve is the rubber diaphragm that covers the radial inlet holes. You can blow it up with a drinking straw.

Bruce,
I thermally insulated the filter housing with fiberglass insulation because the engine oil rarely gets above 60 °C, even in the summer. So low is not good.


The little blue label is a temperature gauge.
 
What type of oil filter works best with the Model A's low oil pressure? I have been using a Motorcraft FL-1A but I believe these were designed for pressures around 40 lbs.
Dan

I’ve been using a Motorcraft FL-1A filter since I installed a Mike’s Affordable full flow oil filter setup on my A. The stock Model A engine has low oil pressure only because it has no restrictions as it enters the valve chamber where it feeds the main and cam bearings by gravity along with the timing gears and eventually the rod bearing troughs.

Adding an oil filter provides a restriction that measurably raises the pressure between the pump and filter. My REX-A-CO oil pressure gauge is pegged at 10 lbs at a cold start. The actual pressure is higher, but drops to 2-3 lbs at a hot idle. The stock oil pump is easily capable of pushing oil through the filter and exceeding the pressure required to open the bypass if need be.

Adding this filter setup doesn’t really much
alter the system as designed, as the oil re-enters the valve chamber very near the stock location. However, I do use the 90 degree adapter and completely fill the filter with oil when I change it, to avoid the possibility of dry starting the engine. It also makes for neater filter changes.
 
However, I do use the 90 degree adapter and completely fill the filter with oil when I change it, to avoid the possibility of dry starting the engine. It also makes for neater filter changes.

Can you post the supplier and part number? I agree that a right angle would likely create less mess, and I'm interested.

Thanks.
 
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