I would like to use the stock oil sender and an aftermarket pressure guage on my 400. where have you guys found a tee fitting for this? i dont want a lot of fittings hanging on my block, looking for a cleaner look. is there a tee w/ the male end off of the 'tee' part so it could stand on its side, w/ the other 2 being female? so the stock sender is the same direction as original, just higher. wish i could draw a pic to explain what i mean. just wondering what others have used.

 

the male end is a short pipe nipple of the same size. 1/8" NPT IIRC? you can put it in any port on the Tee that you want. the term for the shortest nipple they make is "close", then they are referred to by length after that.

 

i know i could use a nipple in a regular tee, i was hoping to find a single tee w/ no other fittings. i probably will end up using a close nipple w/ a tee. are they standard npt? i was comparing some threads and it looked like it might be fine thread.

 

How about taking the second reading from the front of the block. Right by the fuel pump there is a 3/8" fitting.

 

would there be any difference in pressure readings from front to back? is that where some ran an external line from to the back for better oiling?

 

the front port will read direct oil pump pressure, it'll be higher than the reading at the rear port where it will read the pressure after the engine has bled off some of the pressure through the clearances.

the rear port gives a better indication of what's going on. oil pumps rarely go bad or stop, you can pretty much count on the oil pump actually pumping oil unless the screen clogs. if it happens you'll know it from either port anyway. the engine goes bad far more often. it just occured to me that the newer Fords have the sender at the front port. maybe that would be the slick set-up, idiot light sender in front for the and auxilliary gauge in the rear so you can tell if the engine is losing pressure due to excessive clearances?

BTW, with the external line both ports read direct pump pressure and you'll never know what is actually going on in the engine.

 

Go to any GOOD hardware store. What you want is called a "Street Tee". I kind of like to use steel parts when something is hanging out like that and subject to vibration. In that case you would want an Aeroquip #2092-2-2S for 1/8 pipe or a #2092-4-4S for 1/4 pipe. I think that sender is 1/8 pipe tho, -just can't remember. Aeroquip parts are available at some parts stores or hydraulic equipment distributors.

Use an aftermarket electrical oil pressure gauge unless you like a hot oil bath. I also hook up an idiot light to get immediate attention. Murphy's Law states that the engine will lose pressure immediately AFTER you check the gauge.

With an external line you will still know what is going on in the engine. The pressure at the sender will still be the final system pressure at that point which will not be the pump outlet pressure. Trust me on this, I teach Hydraulics.

 

i'll be darned, i thought a street T had the male in the middle instead of on the end, http://www.nextag.com/506085327p/zz2...40426DABF01F76 but like you implied by yelling GOOD, try to find one at a store! good luck

i'm still gonna disagree on the "end of the system" thing though. the external line effectively eliminates the end of the system by supplying direct pump pressure to it, creating a sieve(the engine) in the middle being fed from both ends.

 

Pump pressure is still higher. There is a frictional loss in both paths as well as "leaks" in one of them. The pressure gage will read the pressure at that point not pump pressure. The lowest pressure will be somewhere inside the middle of the engine due to frictional losses but it will be very close to the end point pressure just as the frictional loss in the outside line is small and the pressure will be close to the pump outlet pressure.

What is gained with an external line is a reduction in frictional loss due to volume in the engine. Frictional loss at any point is a function of volume. Cut volume in half and the frictional loss is reduced by roughly half. It is important to remember the pump does not create pressure, it creates flow or volume. The load on the system creates (back)pressure. In an engine the load is the pressure required to force oil thru all the leaks and passages. If there were no leaks there would be no flow losses and the system would operate at system relief pressure plus override. The relief valve used on engine oil pumps is only a single stage with a large override.

The biggest leak I have identified so far in the 351M/400 engine is right at the #1 main bearing. A plug should be inserted in the riser line to the top of the engine at the #1 main bearing. Tim is doing this now after some discussions we have had. There are more mods to do that will reduce flow restrictions and pressure drops but we have not done those yet. Progress is slow and careful.

The standard street tee I have seen the most in hardware stores will have a male thread on one end but all configurations can be found. Fittings are available in steel and brass. All types are available from Aeroquip and many other hydraulic/pneumatic supply companies. They make just about every fitting EXCEPT the one you need... -Another of Murphy's corollaries.

 

beautiful! thats exactly what i had in mind. my local Hank didnt ahve that, but i'm sure i can find one somewhere. i'm planning on using the stock idiot light and an aftermarket guage, like suggested. i like having the light there to get my attention.
so , maybe it says somewhere, but i've never seen for sure , does it pay yo use the external oil line to the back?

 

For a daily driver, probably no. The stock system is OK. An external line makes for another failure or leak point.