ok, it's not on my car..it's on my lil sister's bf's 91 Z28. 305 TPI. so this is what's happening....he was driving around for like 4 hours and no problems, the next day he drove over to our house and then up the street and steam started poring out and his engine was over heating. when i got there and looked at it, his antifreeze was brown. like an orange brown. so tonight we flushed it with one of those prestone kits and man did alot of brown crap come out. i took out the driver side plug on the bottom of the engine and crap came out there (i couldn't find the passenger side plug)....so after flushing, everything was clear water coming out. so when we got to the part where u start the engine and let it run it was fine but then brownish water started coming out. and if u reved it up it was worse. so we flushed just the block and it was clear and then we flushed from the upper rad hose and more crap came out of the rad, so we thought we got it all. we put new antifreeze back in and let it goto operating temp and everything was fine, he ran it up and down the street and it was fine then he drove it home (about a 15 min drive) then back to our house then back home (so about 45mins of driving) so when he finally got home (for the last time) it was overheating again and the antifreeze started turning brown again.... so WTF is going on. like when we were flushing it and the brownish water was coming out, it didn't feel like it was oil and all the other antifreeze/oil mix I've seen were more like a creamy chocolate milk (right??). this stuff was like a clear rust color with the neon green mixed in. sry it was soo long but i need help...PLEASE...i don't know what's up with this

I wouldn't describe it as rust colored, but Prestone Antifreeze with Dexcool is a thick orange color. I suppose with mixing and use it could become brown.



That is what it originally looks like. I don't know if that will help you with the overheating at all. I have just started dealing with too hot Camaro's myself, but this might help you know what was in there already.

i know about Ex-life coolant. at first i thought someone had mixed normal (green) antifreeze with ex-life (red) antifreeze and that's y it was overheating (mixing them breaks down the molecular structure of the 2 coolants) << or something like that. but after flushing and everything i can't see that it was mixed antifreezes since it's back to being brownish and i ONLY put in normal antifreeze

this is the best i could do to describe it... the color on the left was about what the antifreeze looked like when we drained it. (maybe a little more brown)...the color on the right was what it looked like when we flushed it, like what came out of the rad and bottom of the engine. and when we were started the engine and reved it slightly, the water had that color in it. is this rust or oil or what???

Did you try a chemical flush? It sounds like there's some build up in there that is dissolving into the water.

ya, i have some stuff we're gona try next, but for the most part we had everything out. and can anyone tell me where the draing plug is on the passenger side of the block. like i know it SHOULD be in the middle right above the oil pan, but i couldn't find it. like i sed, it's on a 305 TPI a pic would be perfect. o and also what do u recommend for a chemical flush. the only stuff i have is called "cooling system flush made by BG" i got it from the dealership i worked at for when they did flushes. is there anything better???

the pass side block is the knock sensor.

so the driver side is that small steel plug and the passenger side is the knock sensor....oooo ok. thanks

For the overheating...are the fans working? Is the thermostat opening?

It sounds like built up rust in the system. As for a flush, I recently saw a NAPA brand flush that is supposed to be for heavy rust.

It is a granular substance that you first mix in water, then pour into the cooling system. Instructions then say to run the engine for 30 min.

I haven't tried it, so I can't comment on how effective it is, but it sounded like it might do a good job. Any NAPA store should cary it.

for the fans, one runs with the AC right? and the other runs when the car heats up. now the driver side fan will only come on when it's at max operating temp but when it's that hot and u shut the car off then just turn it key so there's power (like so the radio's on and wipers work) the fan doesn't run but it does run on my 84.

but the thing is is that it is overheating bcuz of the coolant, when the coolant was good for a few miles it would barley hit the middle line but as soon as it started turning brownish again, it would overheat

The cooling system probably still has debris in it and is getting clogged. After you flushed it, it relieved it for a short time.

Has the car ever had Dex Cool used in it?

Oh, the orange coolant and green coolant don't get along - they combine in hte system if it wasn't flushed out properly and they get together and start getting real corrosive. The GM dealership I purchased my wife's car was going to void my warranty becasue I wasn't using the orange Dex-cool, nevermind I got the car from them with GREEN coolant in it... morons....

well u see that's what i thought happened at first bcuz of the color of it, i though it had already had normal coolant in it then someone added ex-life, but after flushing and draining, it's still like it, so i think i might be rust

Yes that is rust. My mother in laws 93 caprice has the same thing in it. I just put in a stat and noticed the horrible color. I am about to go get some radiator flush and a flush and fill kit. It is rust from the cooling system getting low and leaving the metal exposed enabling it to rust. When you fill it back up with antifreeze it takes the rust off the metal and circulates it causing the fluid to look brown. Get it all out of there before it ruins the water pump because on a cavalier it is a P.I.T.A. to change. If you have to take out the radiator and get it dipped at a radiator shop. I would say take it to radiator doctor if you cant get the brown to go away.

The reason my mother in laws is like this is because she had a small leak and the system got low on coolant which left metal exposed to hot humid air in the system. Rust happened and when it got filled it just got pulled off and circulated. She had it overheat and had roadside assistance come fill it. That is where the problem started and now I get to fix it.

Get it all out and dont forget to run the heater on high to get out the stuff in the heater core when flushing the system. Figure an hour or an hour and a half to get the prestone flush and fill system installed on the heater hose and a good flush and fill done. Also dont forget the overflow tank it needs to be drained because the rusty coolant made its way in there no doubt.

Wesdog

o ya, i didn't forget about the heater core, i let the engine run and had the heat on high, and his coolant level never got low so idunno y it would rust from it getting to low. but thanks for all info and please....keep it coming

i couldn't find anything about it on thier site

when a system gets rusted up bad it is a nightmare to get it out.
this is what i would do, make sure the fans are working right, then pull the stat out & flush it, then leave the stat out & run pure water in it & drive it normally, flush it everyday or at-least every other day. it takes about 2 weeks or so to get it cleaned up like this, but it does work. don't let it go more than 2 or 3 days max with the same water in it as any longer & it will start causing the system to rust up again. those quick flushes you can get do help, but i would not use them very much as they have chemicals in them that attacks the metals in the system, thats how they work. once you get it clean put some baking soda in it with fresh water & run it a day or 2 & then flush it once more & then put a new stat in it with some fresh anti-freeze.
i would stay away from Dex-a-goo & the other long life anti-freezes.

one other thing, maybe smack your lil sister's bf across the head for letting it get that bad.

Well I got the prestone 10 minute radiator flush. I ran it in the engine for 15 minutes and then left to let it cool off. When I got back I drained the radiator and then hooked up the 3$ flush and fill kit with the little thing you splice into the heater hose to run the water hose to. It said to run the car for 10 minutes until the water came out clear. I ran it for nearly an hour running fresh water from the hose through it constantly until the water coming out was nearly perfectly clear. When it is in the system that bad it takes some time to get it clean. I had the heater on high and just let the car idle with the flush kit on it pouring water/rust/coolant out until it was clear. I drained the overflow and rinsed it out then closed everything up and filled it with the new prestone that mixes with ANY kind of antifreeze. It is an extended life coolant that is green and yes you can mix it with old green stuff or the new extended life.

It may take 45 minutes or more with the car running and the water hose hooked up and pushing water through the system before it gets it clean.

The coolant is now a nice clean green color in the radiator and overflow tank.

Some people will freak out and think that its a good way to warp a head or blow a head gasket but if you just take your time and follow the 5 or 6 instructions on the package it is perfectly safe. If you put cold water from a hose into a very hot engine you can damage it but thats why you do it when the engine is cool. I have done it dozens of times on many different cars and never had a problem.

Wesdog

i would have to agree with u but i can't blame him, he just got the car about a month ago for an early b-day gift and just got his license so he's only really started to drive it this past week or 2.


and r u saying to take out the thermostat all together and just put water in the system? then drive it? and do the dain every few days. and what does the baking soda do. it's a base right? is rust an acid?

Wesdog, i don't know much about the green long life, we use either standard green anti-freeze, or Dexa-goo, which we only use Dex in vehicles that came with it from the factory & still have it when they come in.


chio987,

aah, ok, then he is in the clear on it, maybe he will learn about proper maintenance because of going through this & it will stick with him for life which would be a good thing.

yes, pull the t-stat out & leave it out for a few days until you get the water to stay pretty clean when it is flushed, like i said, do not let the same water stay in it more than 3 days max. flushing it everyday would be better though.
the baking soda will neutralize any of the quick flush that may get left behind. & when you put the t-stat back in, be sure to use a new 1.
rust is a product of electrolysis, you can actually measure the condition of the anti-freeze with a voltmeter, half (1/2) of a volt or more, the coolant needs to be changed.

well last night we flushed it as best we could....we ended up taking the rad out and flushing it with hot water and a leaf blower (it helped ALOT, just hope it didn't mess anything up) and we put it all back together, so far it's good but he only drove 5 miles....anyway here's the pic of the antifreeze....

1. on the left it what was in the rad after letting it sit and cool down

2. on the right is after the car ran for a few mins to mixed it all up.

and after letting both bottles sit u could see the neon green coolant at the top brown in the middle and a redish brown crap at the bottom, like rust . (not shown in pic)

BTW this is after only 15 miles of driving after we did the last flush

Yea I definately ruined my water pump doing something very simular to that. Wouldn't suggest doing that.

o i wouldn't think of doing that. at most i let the engine run for 5 mins then off for 10 min then on 5 then off 10 all while the water was still flushing. the engine never got too hot so i can't see how it could mess something up. i just didn't want to put really cold water into a really hot engine. i just hope we finally fix his prob

Yea me too man, it just doesn't sound good. Great excuse to scrap the 305 and drop in a nice twin turbo BBC though?

http://store.summitracing.com/partde...00436%20300657

Kit #5002. $80 from summit.

Well its been a couple of days since I did the flush and everything seems fine. The water would get heated up mixing with the water that was already in there and since I started off with the engine cool it could warm up to a safe temp. It only got up to about half of the normal operating temp during the whole time. If you dont "shock" the engine with differing temperatures it is perfectly safe. When an engine is getting run in on the dyno many times it is just getting fresh water run through it. Sometimes they have a recirculating system but many dont. If an engine getting run in and tested on a dyno can handle fresh water from a hose going through it then surely an engine idling in the driveway can handle it.

The coolant still looks good.

The new prestone extended life antifreeze is kind of a yellow/green color. Peak also is introducing an antifreeze that is long life and compatible with any kind of antifreeze available. I havent seen the color of the peak brand but the bottle is a bright blue color. We are replacing our old green coolants with this new stuff. If you want to use the old antifreeze you may want to talk to your parts guys and if its being fazed out you may want to stock up. As far as I know the generic brands of "classic" antifreeze is going to stay so if you dont mind using autozone or wherever you shop antifreeze you can still get the green kind.

Wesdog

I just bought the extended life peak stuff and its like a creamy yellow color.....kinda weird buy will see what happens. It says mixes with any kind of antifreeze, hhhm interesting

Its odd that no one has suggested this. If the coolant keeps looking brown after repeated flushes...

Why has no one said head gasket or some other gasket problems?

That looks like a tell-tale head gasket problem.

Overheating, brownish coolant. CHECK THE OIL. Is it the same color?

just a few months old.....

update.....

we ended up taking the rad out all together and hooked the hose up to our sink in the basement and ran hot water thru it and turned it every way so it got all the rust (or whatever it was) out... while that was happening, we were flushing the block and got all that crap out.....put it all back together with a new stat and as far as i know it's still going good....