[2Dragons]

Okay, so I have this 4Runner 1995, v6. I have replaced the water pump, radiator, engine gasket, and I still have those orange stuff (like slush if I leave it too long and not changing the antifreeze often) in the radiator. If this keeps going on, the engine gets very hot and the gasket gets burn again. I need to troubleshoot where these orange/yellow stuff is coming from and what causes it to occur. I know for a fact that it's not rusts. The radiator was replaced less than two years. Any suggestion is much appreciated.

[KidVermicious]

I don't know what that would be besides rust, there's not much else that orange sludgy stuff could be. Give your entire cooling system (not just the radiator) a good flush and cleaning, and then use nothing but Toyota red coolant.

[2Dragons]

I did try to flush and clean it up before putting new coolant in. It's been less than 4 months and it's already yellow/orange again. I don't think the brand new radiator would rust that easily. It's only been two years at most.

[Bad_Vision]

Your engine block may be rusting inside the cooling jacket and if that's happening then you will always get rust because the only way to clean that is a acid dip.

[nicnmike]

Originally Posted by Bad_Vision

Your engine block may be rusting inside the cooling jacket and if that's happening then you will always get rust because the only way to clean that is a acid dip.

I found this write up the other day. Scroll down to the part about anti-freeze. The whole thread is pretty good too.

edit, the link:
http://www.yotatech.com/f116/what-ev...k-3vze-187741/

[ed4stoy88]

A bad radiator cap can cause this ,air getting in your system.

[2Dragons]

Originally Posted by nicnmike

I found this write up the other day. Scroll down to the part about anti-freeze. The whole thread is pretty good too.

edit, the link:
What EVERYONE should know about their truck & the 3VZE - YotaTech Forums

Many thanks for the tips. I'll give those writeup some reading tonight.

[2Dragons]

Okay, here's what it looks like.

[KidVermicious]

$10 says that's rust.

[Bad_Vision]

That's solid rust man I think it's time to acid wash and replace the bypass tube and the lower coolant hose tube to be safe.

[nicnmike]

I believe there are flush kits out there that allow you to hook up a hose to your system. Maybe you could try taking out the thermostat, use the hose to do a constant flush and drain out of one of the drains on the block. This is with the engine off, of course.

[TX_QtPi]

Agreed. rust. Acid wash and replace the water pump n 2 hoses just for good measure if it's that bad.
Cynthia

[2Dragons]

The main question is, where are these "rusts" coming from then? Even if I replaced a new radiator or water pump, it will get like this in about 3 - 6 months. I need to find the source and fix that instead of the symptoms.

[Bad_Vision]

once again ill say it as i stated above!!! the rust is probably coming from the block itself and the only way to fix it is a acid dip.
youll need to replace all your hoses and you water pump and for good measure replace the heater core and the bypass tubes.

[AzDirtRunner]

Check your reservoir/overflow tank. I had the same issue,I flushed it like 3 times and nothing changed. I finally removed the reservoir tank and it had almost 2 inches off crud in the bottom. Cleaned it out and did one more good long flush, my coolant looked way better after that.