View Full Version : Rusty coolant

07-28-2002, 05:58 PM
Anyone know how to fix rusty coolant? I drain the system the best I can and fill it again and it just gets rusted again within a day and doesn't cool right. Is there something I can run through the system to get rid of all the bad chemicals?

07-28-2002, 09:02 PM
You need to fully drain the system, by using the radiator drain as well as the block drain behind the exhaust manifold. It helps to take the thermostat out to get a complete hose flushing. Make sure to turn the heater on high while you are flushing the system. Also remove the coolant reservoir and clean that out too.

07-28-2002, 09:10 PM
You need to fully drain the system, by using the radiator drain as well as the block drain behind the exhaust manifold. It helps to take the thermostat out to get a complete hose flushing. Make sure to turn the heater on high while you are flushing the system. Also remove the coolant reservoir and clean that out too.

07-28-2002, 09:26 PM
run your car like that for a week and do it again until you have a clear coolant
you can also try some flush stuff like prestone!
like dj99 said did you flush all the system???

07-29-2002, 07:56 AM
I can't FIND the block drain plug. I find all sorts of little bolts that could be "that special one" but I'm too chicken shit to just go willy nilly and pull out random bolts. And my haynes repair manual sucks my left nut. It doesn't even show the block drain plug. But if it is such an important step, dont you think they'd show it?

07-29-2002, 08:10 AM
Get on your back, and look up behind the exhaust manifold, kind of behind the o2 sensor. It's difficult to get a wrench on, but it it possible. Don't lose the washer. :)

07-29-2002, 10:45 AM
Can anyone get a picture of this?

07-29-2002, 10:46 AM
Cuz my car is a friggin pain to jack up, and i need to to get under it due to it being lowered. If I'm going to take off my sideskirts again and jack it up I want to KNOW what I'm looking for.

07-29-2002, 11:47 AM
my 87 had the same problem recently, the original radiator was metal and rusted. it was flushed a couple times and rust always reappeared. a new aluminum core radiator was installed. at the risk of sounding real extreme and non-enviromental to get a good flush what I did was take off the thermostat housing, remove the thermostat and open the heater and open the garden hose with a quite strong stream and aim it into the water hose that goes to the radiator from the thermostat. I ran the water until it was clear coming out the thermostat opening. Closed it all back up, added water and alittle coolant, ran it a couple days and did the whole thing again. Then I did a 50/50,
closed it up, burped it, and it has been fine. If you do this make sure that you're in a place that the runoff coolant won't be a problem and tell Jesus in your prayers that night that you're sorry for making an enviromental mess and give a buck to the next homeless person you see. The block plug drain thing really is not worth the hassle in my experience cause you dont get a good flush.

07-29-2002, 01:06 PM
I read somewhere where Hondas use a differant coolent then Prestone,or Peak.
I know Hondas have rust. I flushed mine a simple but effective way. I drained radiator by using lower radiator hose itself. Trying to open any radiator drain is asking for trouble. Then I reattached it onto radiater very very lightly,kinda just caught a little if you know what I mean, then I added fresh water started up 3-g with cap back on. And then waited till the cooling fan came on then I shut engine down & knocked off lower hose with a broomstick very carefully and watched as pressurized rusty water exited quickly,Repeated this SEVERAL times till water exited as clear as I put in. I have not had a overheat condition all summer and theres all boneyard parts: engine/radiator.

07-29-2002, 01:30 PM
you could do that or you can get system flush.
you sliced this thing in to your heater core hose, attach the water hose, open the heater core, open the water and let it run for a few minutes, it should be clear. start the car and run it with a hose on for a few minutes. you should see a lot more dirt comming out.
after few minutes turn it off. and drain radiator. fill it will pure prestone or what ever you are going to use. and drive it.
it will mix it self eventually.
after a few weeks of driving get your self a coolant tester (few dollars) and check what is your status on coolant mixture. if it is too weak drain a little and add coolant. if it is too strong add water.
plus i would recoment add this product to prevent rust in the future http://www.prestone.com/framer.cgi?page=http://www.prestone.com/products/22.htm

PS don't forget to run system flush before you do the flushing. http://www.prestone.com/framer.cgi?page=http://www.prestone.com/products/19.htm

07-29-2002, 06:39 PM
My plan was to change the coolant twice without draining the block because the block bolt is always a PITA. Both times I used Honda Premium Type II premix (don't have to add water).

My coolant was murky brown when I bought it. The first time I just put the heater on hot and drained everything I could out of the radiator. The resovoir was hard to get to without removing the battery, so I just suctioned it out the hose.

The fresh coolant helped, but changing it the second time made the best difference. Didnt' hurt that I took the time to CHANGE THE RADIATOR CAP AND THERMOSTAT, which is a step I highly recommend for you. Also, the second time I changed the coolant I had the battery out, so I pulled the resovoir to clean it out. THERE WAS A COUPLE INCHES OF GROSS SPONGY MUCK in the bottom of the resovoir. I highly recommend going through the trouble of removing the battery to do this.

The coolant looks pretty good now. And my car never runs hot. I feel really good about spending the extra money for genuine Honda coolant, cap, and thermostat. There is hardly anything more important to your engine's than it's operating at the proper temperature!

07-30-2002, 07:16 PM
Thank you thank you thank you. All of you. But even still, does anyone have a picture of this infamous block drain plug?

08-05-2002, 09:26 PM
Picture of the block coolant drain plug?

08-06-2002, 12:23 PM
dude use prestone rust arrestor and corrosion stopper from walmart for under 4 bucks and it does the trick. also see if your radiator itself is rusted, like on the very bottom. if so. either change it, get one from the trunk and use liquid copper and it does the magic

08-08-2003, 07:34 PM
I'm fighting the same battle now, just bought an abused LXi that looks like someone poured nestle quick into the radiator, its THAT brown.. I used prestone superflush drove it for the 6 or 8 hrs over a week, drained it then did it again, I'm on my second can now. I also used their flush kit, just cut my heater line and attatched it clamped it down and hooked the hose to it. Run it til the water runs clear with the car running and heater on full, then I shut it down and let it run some more, If you bring the idle up it forces the water through and cleans a lil better. Becareful though because on our cars the kit forces the cold tap water right to the thermostat which may cause it to not open because the cold water is cooling the thermostat as the block's temp is increasing it

08-08-2003, 09:00 PM
our block being cast Iron doesn't help either.....

But pouring the coolant into the water drain doesn't do a real environemental mess, it's written on the bottle that you can do that :)