ORXJ97

Just finished a cross country road trip and I noticed along the way my coolant began to turn brown. My Initial thought was that I was getting oil in the coolant lines and that I had possibly blown my head gasket. But after looking at it more I realized there was no oil being separated from the water and that it wasn't foamy like you'd expect from a blown head gasket, and there was no coolant in the oil either. I just did a coolant flush and drove it around for a few miles and it's still brown. I did an engine swap a couple months back and the engine I'm using had been fairly rusty and needed to be flushed and new freeze caps. Could this engine still be dirty on the inside?

PatHenry

Yep - you may need to do multiple flushes on it to get the coolant clean.

EEVEE

i used that garden hose adapter thingy and that made cake work of the crap in my engine, I did a hack job getting the thermostat out for a temporary solution to bypass it and clean it further as the water was to cold and couldnt really heat up the engine or thermostat and it remained closed but yes i took it out and flushed it until the water turned clear. Then i used the prestone rad flusher with distilled water and repeated that process 8 times over a week period until the water was once again clear enough to add coolant, Then there is a trick to doing it i forgot the amount of concentrated coolant to use but i think its a gallon and a half then top the rest with distilled water because the engine holds coolant in certain spots and itll all mix in for a 50/50 mix.

Chris Lippold

Its definately dirty still. I'd flush it every year and after every long trip till it starts looking better.

95XJPrerunner

Was having the same issue. So I just replaced all the hoses. Figured there was a lot of dirty/rust residue on the inside of them. Perfectly clear now and golden ever since.

dave1123

Everybody forgets about the block drain! There is at least one plug at the bottom of the block water jacket so you can get all the coolant out along with any sediment that settles in the bottom. If you don't drain that crap out once in a while, it'll build up and you'll have to probe the plug hole with a screwdriver to clear it. That crap may break up after a long high speed run or after a near overheat situation and turn the coolant brown.

You should see some of the junk that comes out of an engine that people have used well water in! Around my area it's called "liquid limestone!" Store bought 50/50 mix is at least filtered municipal drinking water, the kind you buy in a bottle. People are reluctant to use distilled water because they think it's more expensive. It's not more than 10 cents more a gallon where I live.

Here's a trick I use for a perfect 50/50 mix when I buy full strength coolant. Find an empty 1 gallon plastic jug. Fill it with 1/2 of your distilled water, then fill it up with the coolant. Pour the second half of the distilled water into the coolant jug. Now you have 2 gallons of a perfect 50/50 mix. If you need more than that, do it again and keep it on the shelf for topoffs or the next time.

firebane

This is from my GC 5.2 .. Figure that out lol.