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From: The Firebird spent most of it's live through the winters of Indiana. Now in D.C.
Coolant on top of the engine???
I was inspecting my engine while trouble shooting my EGR valve. I found liquid on top of the engine in some of the screw wells, and other dips on top of the engine.
1. I thought it was water from when I went to the car wash the previous day. I figured it would be gone if I took the car out for another drive.
2. It didn't evaporate yet! It must be coolant?!?!? I have no idea how long coolant been sitting on the engine, and what damage was being caused.
3. up on inspecting around the thermostat housing, I saw a half crusty trail of coolant around the edges.
4. It's very weird that the coolant didn't drip straight down. Instead, it followed the contour of the thermostat mounting bracket and flowed back up toward the engine. It's due to surface tension of a liquid; like how moisture on the outside of your bear can flows to form a perfect ring on your wife's freshly polished table.
5. Using a screwdriver I pushed napkins down to the crevasses of the engine, and soaked up all the coolant. By the color, it looks like it's time for a coolant flush.
6. I cleaned up the metal, and I replaced the thermostat and gasket.
7. problem solved. Remember to inspect your engine's nooks and crannies regularly. Don't just go for the dip sticks. (umm, what. . . . maybe that doesn't sound right! LOL) Under the EGR hose your can see the thermostat mounting with semi dry coolant sludge. Do you see that I have a screw missing? I had my engine rebuilt in 2014, and just seen I have a screw missing! SMH, no attention to detail. I wonder if that's the cause of another air flow problem that I'm having with my EGR? (I have another thread that I posted "HELP me: EGR trouble code P0405".) To the right of the thermostat you see where I stuffed napkins to soak up the coolant in the dips and well on top of the engine. It's weird how the coolant didn't drip straight down, but flow backwards toward the engine. It must have been a very slow leak, I guess?
Last edited by BimRon; Feb 23, 2022 at 09:04 AM.
Reason: Found empty screw hole in 1st pic. Engine rebuilt in 2014!
It's weird how the coolant didn't drip straight down, but flow backwards toward the engine. It must have been a very slow leak, I guess?
Not weird. As the system heats up, it pressurizes, which the pressure cap regulates. (As the pressure gets too high, excess fluid is released to the overflow tank.) If you have a leak, pressure can cause fluid to squirt out and defy gravity.
From: The Firebird spent most of it's live through the winters of Indiana. Now in D.C.
In the top picture, there is an empty screw hole (to the right of the thermostat mount bracket, on the engine). My engine was rebuilt in 2014, and it looks like a screw was missed. I couldn't show it with the camera, but it look like a gasket between the two metal pieces where the screw is missing. Do you know if coolant travels that path in the engine? I need to figure out what screw that is, so I can replace it.
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Coolant on top of the engine??? 
