When i got home this morning, I let it idle and i opened the hood to take a peek at some recent work I did. When I looked over at the over-flow bottle, there was barely any coolant in it (bubbling a little at the very bottom). I quickly shut down the engine and watched as coolant refilled the bottle to just under the line... sooo...

Is this normal?

Ambient temp 60F
Coolant temp 80F

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'81 300SD- OM617.951, Euro Head Lights, Hella 550's, 2.5" Turbo-Back Straight Pipe, ALDA Removed, Camo Dash + Seat Covers, Boost Gauge, DU Floor Mats, Cobra CB, LED Trunk lights, and other things...


'03 Chevy CCSB LT LB7 "P-Stroke Killer"
219K mi. - AirDog II 165, EFI Live, Alligator Stage V, ISSPRO EV2 Pyro/Boost, PPE Boost Valve, LML Manifold, MBRP Downpipe, Debadged, Bills Custom 3.5" Turbo Horn, B&W Hitch, S&B Intake