Engine problems, no oil pressure

[suburbanK-2500HD]

Hi

My brother inlaw has a 1997 Tahoe 6,5td, stock.

This is wath happend.
He changed engine oil, refilled and tuned to proper level.
When he starts the engine there is no oil pressure, and the "check gauges lit up".
He called me and i told him to check if the OPS is connected, it was.
Then he starts again, and there is a strange sound. I drive over to him, and disconects the shut off solenoid. Cranks the engine, no mecanical noise. Reconnects the solenoid and fires up, its a puffing sound in the airfilterbox. Seems like the engine i sending compression out the valves.

How can this happend after a oil Change.
Could the oil pump axle be broken ??, i guess the lifters wont work for long if there is no oil present....?

Any other ideas

Børge

[TAG]

Had this happen once on a friends 97 after an oil change. Took off the new ac delco filter & installed a wix off my shelf. No issues for the last 5 years.

[racer55]

Lack of oil to the lifters will let them bleed down and the valves won't open properly.
Sounds like the intake is opening but not the exhaust on at least one cylinder.

[suburbanK-2500HD]

Hi

He let the engine bleed for 3-4 hrs before he filled the engine.
Could this cause the oilpump to bleed out so much it wont pump.
He didnt change the filter, but will do so to test.
Is it any idea to fill 0,5ltr in the hole where the CDR valve is.

[suburbanK-2500HD]

Problem solved, filled 0,5 ltr oil in the CDR valve hole, all ok.....