Hey guys, I'm looking for possibilities as to what could be the issue... A while back i noticed my Z started getting hotter and hotter, so i check the water. To my suprise, the water level was low, and there were some reddish brown gunk that had bubbled out of the reservoir. The anti-freeze was actually brown, and it looked like it had something which resembled the size of sand in it, that too was also brown. The car hasn't shifted right since i got it on the road 2 years ago, so i figured i'd rebuild the engine. Just this passed half hour, i hosed out the block, and the water poured out straight brownish / blackish... anyone have any ideas? the fluid also appeared to have a very small amount of rainbowing due to some type of oil, though i can't see it being from an oil leak. I'm not sure how long the engine sat before i tossed it in, so i mean, could it be some kinda rust or something? it smells like metal

 

Bump, hope you get some ideas, How long has the car sat? and when was the last time it was flushed? Before you just did it?

 

the engine came out of a.... cadillac? i believe? and not sure how long it sat... i ran detergent in it for a week straight after flushing several times... it had some serious build-up in the block

 

Check your engine oil

If it looks the same, headgasket. Needs rebuild ASAP

If oil is fine, someone mixed green and pink antifreeze and you need to flush the system ASAP. It will turn to mud and solidify

 

oil came out dark, no real issues in there... i took a dry chunk of the stuff that came out of the block, and it was like a powdery brown stuff, i put a magnet to it, and it stuck... so it's some kind of rust or something... anyone know of some kinda adder i can put in to break down rust after she's all back together? i flushed out the block and everything as best i could

 

Get a flush kit from a local parts store and run that through it

Think of it as heat activated engine detergent

 

appreciate the input, i'll see how it looks after it's back up and running...

 

if you have it stripped down to the bare bock, go have it hot tanked, that will take care of 99% of any kind of build up

 

"Chocolate milkshake" -as a lot of people call it- is oil in the coolant system for one reason or another.

 

Automatic? Sounds to me like you burst a tranny cooling line inside the radiator. Suprised someone hasnt mentioned it.

Its either that or a headgasket, I would check the trans lines in the radiator first before you did anything.

Take the Radiator out drain it completely. Cap the main upper and lower hose ports, fill it with water and if any water starts coming out of the trans lines/ports that is your problem.

 

Might just be the block cleaning itself. If it sat around for a while the coolant passages would have grown a bit of surface rust, especially with lo coolant. The heat cycling of resumed normal operation is shifting it.

I managed to overheat my engine a few months back thru the fans not coming on. Coolant had been nice and green for years, but that event turned it brown with bits of grit etc. Flushed it - nice and clean again ever since.