Rusty coolant

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irowiki
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Rusty coolant

Post by irowiki »

I checked the coolant in Pokey as part of my normal routine and noticed a huge buildup of rust on the radiator cap and underneath it.

Also, the coolant was actually water (it is a really good thing I checked, we're getting freezing temps this week), so I drained that out, it was dirty but not too bad. Put a can of cooling system flush in, drove around for an hour, drained it, and it was really dirty, brown with rust!

So I dropped a larger can of cooling system cleaner in, drove for 150+ miles, drained it out, and it was even more rusty!

Drained that, filled her with distilled water, ran her for fifteen minutes, drained that and it is still rusty.

Should I keep flushing with distilled water until it runs mostly clear? Seeing that I may be replacing this engine soon I'm not sure how much effort I should put into getting it perfectly clean.
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87 Corolla FX16, 105k
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TURTCEL
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Re: Rusty coolant

Post by TURTCEL »

You can also pull the thermostat out and put a garden hose directly into the upper rad hose and flush the system with fresh water and then replace with distilled after that. A little city water won't hurt the car if the rust hasn't. I have done this on an older Toyota pick up that I had...worked well.

Peace
1985 Tercel 4wd SR5 Wagon, WEBER Carb, Brown (TURTCEL)
1988 Corolla DLX All-Trac Wagon, 4 speed AT, Silver (Wife's new car)
1993 Ford Escort Wagon LX, 5 Speed, Smurf Blue (Smurfette)...selling
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irowiki
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Re: Rusty coolant

Post by irowiki »

Draining it while at work (yeah, I'm bored) and it already looks less dirty!

I think I'm just going to drain it 1-2 more times then put antifreeze in it, supposed to freeze tonight :shock:

If the oil consumption problem solves itself I'll probably do a proper flush at some point, otherwise the engine is coming out anyway.
Former Tercel Enthusiast (not a practical family car anymore but they still have a place in my heart)

Site administrator, if something is broken, PM me!

87 Corolla FX16, 105k
94 Jamboree RV (Ford E-350), 90k
95 Camry Wagon, 197k
05 Avalon, 199k
scouttster
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My tercel:: 1984 Tercel Hatchback
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Re: Rusty coolant

Post by scouttster »

Many will knock me on this, but if you can find some powdered laundry detergent with " PHOSPHORUS " in it.. Tough to come by nowadays - it works wonders... Phosphorus activates or oxidizes steel oxide ( rust ) Fill it with water and add a few tbsp. of the powdered stuff and drive around for awhile.. You'll be amazed at what comes out and how clean it gets.. Then flush and rinse several times with clean water. Coooell beans!! :shock:
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Re: Rusty coolant

Post by TURTCEL »

Hey irowiki, is Pokey the Terc you just picked up?

Peace
1985 Tercel 4wd SR5 Wagon, WEBER Carb, Brown (TURTCEL)
1988 Corolla DLX All-Trac Wagon, 4 speed AT, Silver (Wife's new car)
1993 Ford Escort Wagon LX, 5 Speed, Smurf Blue (Smurfette)...selling
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Petros
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Re: Rusty coolant

Post by Petros »

it is fairly normal to develop rust in the cooling system, particularly if the car sat around without being driven. Coolant is supposed to have rust inhibitors in them, but they are not completely effective in stopping rust formation, that is why it is considered normal maintenance to flush the cooling system every two years, to limit the build-up of rust deposits. It does not really harm anything as long as it does not build up too much.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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irowiki
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Re: Rusty coolant

Post by irowiki »

TURTCEL wrote:Hey irowiki, is Pokey the Terc you just picked up?

Peace

Yeah!


Peter: there was no coolant in there though, hence my concern.
Former Tercel Enthusiast (not a practical family car anymore but they still have a place in my heart)

Site administrator, if something is broken, PM me!

87 Corolla FX16, 105k
94 Jamboree RV (Ford E-350), 90k
95 Camry Wagon, 197k
05 Avalon, 199k
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Petros
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Re: Rusty coolant

Post by Petros »

chemical coolant is a relatively new invention, all engines ran on plain water up until the 1970's or so. it was normal in freezing climates to drain the water after each use, or if used regularly to use a block heater to keep it from freezing. Using antifreeze was a "new" innovation and was a hard sell to most car owners until it became standard equipment on new cars.

I can remember seeing commercials on TV convincing car owners what a good idea using Prestone anti-freeze/anti-boil in their car. they actually sold it on the basis that it would prevent boil over on hot days, and improve cooling (false: plain water actually cools better). No harm comes from running plain water if it is kept above freezing.

Now that I think about it, it had blown the head gasket on the drive north in July and it lost much of the orginal coolant. I had to stop and top it up several times with filtered water until I found a place I could change the head gasket. when I drained it to change the head gasket it still had some pale green color to it. once repaired I poured the coolant back and topped it up with filtered water. It completely slipped my mind to put some anti-freeze in it after I got home (I was just grateful I was back on the road again). I would have checked it before the weather got cold, just like you did.

So it only ran for a few months on a very weak mixture of anti-freeze and water.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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