Oil pressure reading ??

[badmix]

Ive noticed my oil pressure has been reading a lil higher then what im used to.

1984 K5 305cid w/ 160k. only mods are Holley 570cfm carb and headers, all emissions removed.

its reading 55-60 on cold, once its warmed up, seems to be around 35-40 or so.

 

[Bent77]

The warm number is normal.

How has it changed, and is there a different brand or weight?

 

[badmix]

no i dont think so, I changed the oil a couple months go, I dont drive this truck often (1-2 times a week), I always put some kind of oil additive in, this time I used Lucas OIl treatment, I know its thicker, so maybe that is whats doing it.

 

[diesel4me]

Lucas and other oil thickeners like STP,Motor Medic, "Stop Smoke",etc,will make the viscosity thicker and improve oil pressure on older engines with some excess bearing clearances..
That can work against it in cold weather though,by inhibiting cold oil flow after a cold start--some parts can suffer while waiting for the thicker oil to pump up and reach them...the film Lucas and the other stuff leaves behind tends to not drain off though,so its a toss up as to whether it hurts more than helps..I have used those additives and had good luck with my engines,but in the dead of winter I dont add them..

 

[badmix]

Yea i know I had rough time this winter, so I guess ill change the oil in fall time, go with thinner weight and no additives.

 

[diesel4me]

I used to run a smokey 283 in a '67 Impala on a mixture of three quarts 20W-50 and two cans of Motor-Medic or STP,it had worn rings and valve guides--after a friends sister borrowed it one night and forgot to push the hand choke in all the way,it was never the same again,and would smoke badly after a period of idling like at a traffic light (or a drive thru fast food joint !,when you stepped on the gas..

I ran the car for months on that mixture in the crank case,but come October or November,the first cold snap resulted in a no-start condition..the oil was so thick it'd kill the battery in about 10 revolutions..then I'd have to switch back to 10W-30 for the winter,and hope no cops pulled me over for smoke screening...as long as it stayed below 30 degrees it didn't smoke that bad,unless I took a highway cruise...then I had to add a quart of oil like every 100-200 miles..