Topic: Oil pressure

[trent86]

Can anyone help I have a 60,000 mile 65 289 Mustang auto coupe which has been running fine up until a recent oil change. I initialy used a 1040 synthetic oil which obviously didnt go down too well as the oil light came on as soon as it reached operating temp on tickover. I changed the oil back to a 2050 mineral oil in the hope it would resolve the problem but the oil light still returns on tickover but it does at least go out when revved. There is no indication of any damage, noises, smoke any thoughts gratefuly recieved

[66GTKFB]

Older engines had very lose engine tolerances so a thicker oil was used. I would recomend switching to 30 or 40 weight oil might help but plan on a rebuild.
Jim

[Soaring]

Sounds like a weak oil pump to me.  My 65 289 has 130K miles on it and the oil pressure is just fine.  If it were mine, I would drop the oil pan and replace the oil pump. 

[Jeff73Mach1]

I think your synthetic change freed up some crud and now the oil pick up is partially clogged.

I agree you need to drop the pan, change the oil pump and clean the pick up and everything you can.