1946 Willys Jeep L-Head Oil Filter Assembly Question

[Doug Bennett]

I am replacing the Oil filter assembly with a new OMIX-ADA unit, but I need to locate the NPT to flared fittings that go on the oil filter reservoir and appropriate locations on the timing cover and block for the supply and return lines. Do you happen to know what size these may be and what the flare type is? I have some reference material but the original Willys part number is of no use it seems at the local parts house (NAPA).

 

I have crudely circled the points I am inquiring about in the image.

[Moses Ludel]

Doug...This is a very common adapter and should be in the Weatherhead fittings at NAPA.  You're right, this is NPT to a flare nut.  NPT is 1/8", 1/4", 3/8" and so forth, easy to identify in this instance by the canister threads.  The flare seat thread is based upon the required tubing diameter, which also determines the flare nut size. 

 

The lower end of the canister to the block is an oil hose.  Here is a link to a Crown part and illustration that should demystify that oil hose:  http://www.partstrain.com/store/details/Jeep/Willys/Crown/Oil_Line/1946/J0910290.html?source=productads&c_aid=43257666626&c2cid=6aeae580-27fc-487c-af51-b89ded673350.  Crown is popular, and this part number is available through a variety of Crown outlets.  Omix-ADA should have it, I would think.

 

Note: The easiest way to match up a tubing piece with flare nuts is by measuring the flare fittings with an open end wrench.  Tubing size is always matched with the flare nut size. 

 

If the canister is off the engine, take it to NAPA to match up the NPT thread size.  NAPA will have flare tubing for fuel/brake that is already sized for length and has the flare nuts and double-flared ends in place.  Just pick the correct length tubing with flare nuts in place and bend accordingly.  Bending can be done with any of the bender types, the better quality benders make smoother radii and are less likely to kink the tubing—which will have you buying another piece. 

 

Many of the Jeep lines were copper clad.  This is not the same as copper tubing;  copper clad is actually steel tubing with an anti-corrosive copper coating.  Brake lines are always steel, double flared and rated for brake use even if copper clad.  I always use steel fuel lines with double-flared ends and flare nuts. 

 

The most common usage of copper tubing was the mechanical oil gauge lines in vintage vehicles.  (Since the late 'sixties, nylon tubing has been common unless you want authenticity.)  Copper tubing is commonly ferrule fitted, using ferrules, compression nuts and brass ferrule seat fittings.  Single flaring a copper tube end is unacceptable for automotive use.  A single flare copper end is likely to split from vibration.  Double flaring is not practiced with copper tubing, copper is too soft and will not tolerate the flare fold and compression...Single flare copper tubing is for residential plumbing.

 

See the Summit Racing catalog for brake, fuel and oil line ideas...Very helpful.

 

Moses

[Doug Bennett]

Thank you so much for the detailed info Moses. The detail in your reply is so very appreciated. You my friend are such a wealth of information and professionalism. Now, on to complete the oil filtration system on the Willys as I now know better what I need to do and look for to accomplish my objective. Sometimes when dealing with vintage components it's hard to find enough detail to make a proper repair or functional recreation of certain parts. Thanks again!

[Moses Ludel]

You're very welcome, Doug...As a footnote, when fitting up oil hoses and brass hardware, I use PTFE paste on the threads.  Do not use Teflon tape here.  The best practice is to smooth a uniform coat on the male threads only.  Keep Teflon paste away from the fitting ends to avoid exposing the oil system to the paste.  Wipe fitting ends clean, leaving the even coat of paste on the male threads only.

 

The alternative "in the day" solution is Permatex Super 300 or equivalent, brush applied.  (Here is the scoop: http://www.permatex.com/products-2/product-categories/gasketing/gasket-sealants/permatex--super--300--form-a-gasket--sealant-detail.)   The Teflon paste is also a Permatex product, and here is the overview:  http://www.permatex.com/products-2/product-categories/thread-compounds/thread-sealants/permatex-high-temperature-thread-sealant-detail.  These products are widely used by automotive professionals. 

 

You can install and torque up the fittings, then while the paste is still pliable, wipe off the exposed excess, leaving an attractive "original" look without visible PTFE paste or Super 300 Form-A-Gasket.

 

Moses