My oil pressure was slow to build after startup FIXED

[rabbitman]

So in the past half a year my oil pressure started taking waaaay too long to come up after startup, I counted once and it was something like 3 seconds which I'm sure was horrible for the engine. Had OK pressure after that though.

To fix it I pulled the oil pan to clean the oil pickup screen and also removed the pickup tube to get at it better. The screen had little bits of rtv (not from me) stuck in it way at the edge were I doubt it had any effect. The big thing is I noticed the pickup tube o-ring was hard and almost brittle so I stuck a new one on.

Normally I fire it up and scan the gauges and would see the oil light on still for too long but after doing this by the time I looked at the gauges the light was out. So since I kept missing it I made a point of staring at the light and gauge to see how long it took. Takes very little time, like as soon at the engine is running the light goes out. If the coolant temp is not hot but too warm for the GP's to light it takes a bit more cranking and usually when it starts I have oil pressure.

So, it was an easy fix for what seemed like a worn out engine..........

Since then I haven't driven it far enough to get the oil totally up to temp to see the running pressure.

[ORCoaster]

I'm puzzled.  How can an O ring immersed in oil get hard and brittle?  Just old and non pliable after all the oil around it? 

[CRSMP5]

engine heat... and i will not say its immersed either..

[8v-of-fury]

The O ring is stuck between the pickup tube and the rest of the pump. I doubt it sees much oil as it is sandwiched between two pieces, and it is certainly not immersed in oil.

But i bet she does get some hot! lol

[rabbitman]

I'm puzzled.  How can an O ring immersed in oil get hard and brittle?  Just old and non pliable after all the oil around it? 

If it was immersed in oil it wouldn't serve a purpose since oil could be picked up through it too and the pump doesn't care where the oil comes from.

I don't know why it was so hard but it's bad enough that when I squeeze it together so the sides touch it stays egg shaped for a few minutes before getting round again. And pinching it feels like pinching insulated wire..........

[ORCoaster]

Sounds like a heat issue to me.  Thanks for the read.

[rabbitman]

Sounds like a heat issue to me.  Thanks for the read.

It now has a saab oil cooler on it so that shouldn't be a problem anymore.

[Toby]

Hot oil pulls the plasticizers out of neoprene and Viton. They will always get hard when subjected to it.

[rabbitman]

Hot oil pulls the plasticizers out of neoprene and Viton. They will always get hard when subjected to it.

Good to know, I probably have lots of other seals about to let go to then.

I didn't think it should get hotter than any other NA out there though, I like getting good mileage so I try to cruise with the EGT below 650F and I run it pretty easy even when I am hot roddin'. I don't have an oil temp gauge so no clue how hot it really gets.