I'm glad you solved your problem. 

I love the Internet and forums.  It allows us (enthusiast) to share information and find information that would be very difficult to obtain without it.  Because of the online medium, I really feel like the world is a whole lot smaller.

90’s Ford trucks have a piece of rubber that attached to the condenser with plastic snaps to direct air through radiator.  It even has a Ford engineering number molded into it.  Looked like it may have been available in different widths...as I recall.  I have seen the use of the window air conditioner foam to seal that void too.

While 20 psi may not sound like much, it's fine as long as it rises when you rev it up. The general rule of thumb is 20 psi at idle and 10 psi for every 1,000 RPM. My 351W has almost 70K miles on it and on hot days the idle oil pressure will get as low as 20 psi but it jumps up to 40 psi when I take off and it hits 50-60 psi when I jump on it. Now 133K on your engine is still quite a bit but I would take a compression test before thinking about rebuilding it.

What THEY^^^^^^^^^^^^^ said!
Don't judge your oil pressure by what a 'shivel-lay' engine makes.....Those guys run 40-60 psig because their engine oiling system is NOT as efficient as SBF. Its just a fact.
  Excess oil pressure is hard on the distributor drive shaft and suck up a bunch of HP.
It ain't a Shivel-lay........its a Ford!
6sal6

I wouldn't bother and would just keep an eye on the current pressure to see if it drops some more before pulling anything to examine. Keep an ear out for lifter clacking as that will be your first sign that your pressure is too low. I wouldn't be surprised if it was the sending unit as I have run across sending units doing odd things like this. One boat with dual Volvo-Penta AQ271/AQ290 I/O systems that I worked on had a defective unit like this. His oil pressure was linear and one day it started bouncing between 20 at idle and 40 on revs while the other engine gauge was acting as usual. I checked the pressure on both engines with a manual gauge and then swapped gauge connections (problem moved to other gauge) to verify if it was the gauge or sender. I changed out the sending unit and the problem was solved.

If you tear into it I would just do a rebuild (or go with a 302) and get it over with, thus my inclination to let it ride for a bit and see if it changes any more. In the meantime, plan for that new engine and do it when you're ready to get it done!

Do you trust the gauge? Have you used another mechanical gauge to verify the drop in pressure? After talking with Steve Buzek today about a similar experience him and Glen had, the oil filter could be bypassing.

An oil and filter change would be easier than pulling the pan. And you cut open the old filter to check for metal. If the pressure dropped that quick due to bearing clearances opening up, there should be evidence in the filter.

Last edited by Bolted to Floor (9/01/2019 10:27 PM)

I changed the oil Amsoil 1040 with zinc and filter WIX when I first saw the problem I will watch this now as I don't need to watch the temp as close. we seem to be holding on the temp side. oil pressure when i start up is 55. That 20 PSI is also in gear as I have a C4

Cab4word67 wrote:

Crap temp seems to be more normal

Glad it’s running better, but this is a little too much information!!