Keaton

2000 4.0 auto

Heres a list of symptoms :

Operating temp is about 215-220*
Heater blows cold, except when at freeway speed, around 2k rpm, where it blows hot
When on defrost/floor mode, hardly any blows on floor, mainly comes from defrost
Dash vents do work when switched to that mode though

The other night i noticed a small leak coming from my passenger side of radiator. It was dirty brown water and it was cold. I made a thread about it and they suggested i have a clogged radiator. Hasnt leaked since though.

Any thoughts about either problem? Is there air in my system? Last time i added water, i didnt have the heater turned on so maybe thats why?

ZINGGG

Drain the cooling system, take off all components of the cooling system (water pump, thermostat, radiator), flush the block by sticking a hose in the thermostat hole and waiting till the water is clean that comes out of the water pump hole, flush the heater core using a garden hose, then replace with new water pump, thermostat and radiator (might also want to replace radiator cap, hoses, thermostat housing and fan clutch at the same time).

And yes you should replace all components. Spend the money to do it. You don't want to overheat your engine. You have the fragile 0331 head and if the cooling system isn't in tip top shape, you may find yourself replacing the head, giving yourself a much larger headache.

Edit: And as far as air only blowing mainly at defrost and not so much elsewhere, take a look at all vacuum lines to make sure they aren't cracked and properly attached.

Keaton

Forgot to say i replaced water pump about 7,500 miles ago. As soon as money allows i will replace the rad, t stat and cap. Right now i just need to get a handle on this til i have the extra cash.

Ill go ahead and do the heater core flush and radiator flush first. Do those radiator flush kits work or should i just flush it with a garden hose?

djb383

On a 2000 model, having the heater on or off makes no difference when adding coolant......there's no heater control valve to open/close. If u have a coolant leak, u can bet u have air in the system. My thoughts r, u have 3 choices 'til u do the repairs: 1, Carry plenty of extra coolant with u and check/add to the coolant level in the rad each time before starting the motor or 2, Borrow the money to do the repairs today or 3, Park it today. +/-$200 for the cooling system parts u haven't replaced or +/-$2000 for a motor. Member for almost 4 years with over 400 posts and today we're taking about dirty brown water leaking from the radiator and overheating....really?:brickwal l:

Keaton

This is indeed the oem tech section, on a forum, where people ask questions, correct? Dont like this topic, then just ignore it. Your reply was helpful for the first couple sentences. Should have ended it there. I dont need your sarcastic bs.

djb383

If I got u to think about your situation just a little bit more, then I did some good. If u don't think about your situation a little bit more.......cha-ching, cha-ching. I apologize for the 2X4 between the eyes. What I said was unnecessary/uncalled for, but think about it.

ZINGGG

He's actually the most knowledgable person you'll find here when it comes to the cooling system.

Your water pump should be fine since you replaced it not all that long ago. I'd replace everything else though as soon as you can. And I'd pick up a new water pump gasket so that you can pop off the water pump to flush the block when you do the work to replace everything else. Like djb already noted, you should drop the little bit of cash now so you don't have to pay the big bucks for a new engine later on.

bigbadon

Sounds like the classic case of OAT coolant turning into a brown, highly corrosive mud. When it turns brown it will eat gaskets,plug heater cores and radiators. Clean system with cascade for 30 minutes then flush,flush and flush then fill up with coolant. Never let the plastic overflow bottle run empty as this will allow air to enter coolant system and create this mud.

tjwalker

If you find a radiator leak, you should REPLACE that radiator. PERIOD.

Small leaks can turn into big leaks in a micro second. And then, you'll have bigger fish to fry!

Tolerate NO leaks from any cooling system components.

Good luck!

djb383

If I'd have just said it as nicely as 1996 and tj......again, my bad.