oil pressure light on-question

[downbytheriver]

68 c10, 250 six

I fired my truck up today after it sat for the past two days. The last time I drove it, it gave me no problems. Today, as soon as I turned it on, the oil pressure light came on. I turned it off and checked the oil, which was full. No leaks or puddles. I then drove through the neighborhood and noticed it was running a little rough, so I took it home. If I revved the motor, the light would dim in relation to the RPM. It has rained a lot in the last two days, and the truck has been outside if that makes any difference.

My thought is to check the pressure with a mechanical gauge tomorrow, and replace the oil pressure sending unit, but I wanted to see if anyone had any ideas on other things to check. Thanks fellas.

[GMtrucknut!!]

Yes definitely do that and before you check it with a mechanical gauge crank it over to be sure no sludge has plugged the passage to the sending unit which will give a false reading.

[downbytheriver]

So pull the sensor (I think I found it...right next to the starter on the block with a single wire?) then fire it up and see what comes out?

[GMtrucknut!!]

Just make sure oil comes out then install your gauge to check it .

[Steeveedee]

It's going to puke oil all over if you do that! Pulling the sender off should allow oil to drip out. Peek in there and clean it with a wire or something if there is sludge built up there. Then put a gauge on it.

[GMtrucknut!!]

I usually don't try to clean it with a wire or anything as you can further lodge debri in the passage

[vegadesign]

i had the same problem with my 250 and the sending line was pluged up

[Rufton]

Better replace oil filter before starting again.
If new oil filter solves pressure problem then expect to see metal flakes from bearings inside removed oil filter.
Good luck and I hope it was sending unit not plugged filter.

[downbytheriver]

Well, finally did the oil change after a weekend of nothing but rain and everything looked good, so I replaced the pressure switch. All is now well with that...thanks guys.

NOW I fired it up and let her come up to temp, and the water outlet cracked in half. D'oh! I have a 195* thermostat in there. I also noticed the vacuum advance hose wasn't connected

[vegadesign]

I run a 180 and no temp gauge lol
Truck runs super cool even with the clutch fan and the tiniest fan shroud ever
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[downbytheriver]

Haha yeah, no fan shroud here...i do have a 160 tstat at the house, but i think that's too cool
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[Rufton]

I run 195F T-stats and no fan shrouds.

[vegadesign]

If you've seen the stock fan shroud for mine in like putting foil over the fan to prevent fingers
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