My recently purchased 93 3.0 aerostar auto was leaking a little antifreeze, so I decided to change it and flush the rad. The antifreeze was not green as I expected but brown. I flushed rad several times ran some prestone rad flush through system with heater on and engine running--drained and flushed again several times. To my suprise instead of clear water it was still brown.

I can't figure out what's wrong the engine oil is clean and not frothing the tranny oil is not bright red it's a little brownish.
Is it possible the tranny fluid is contaminating the antifreeze???
Any suggestions are welcomed.

 

Your previous owner was attempting to seal a leak in the cooling system. The brown color is from the leak stop. Best off continuing to flush until clear and then find and seal the leak the proper way, else come summer.....

 

It may not be a stop leak that is causing the brown color but worn out antifreeze. I have seen the brown coolant in cars that have not had the rad coolant changed after 20 or 25 K miles. Saw it in a one year old car that had 30 k miles on it in less than a year.Brown is bad.:-X23

 

Three possibilities come to mind:

a) It may have had that orange-colored coolant added to std green-tinted coolant. I assume that green + orange might = brown.

b) Barzleak (or equivalent) stop-leak stuff can change your coolant to the damndest shades. As both the heater core and the radiator on my (well worn) '89 began leaking within two months of my acquiring it, and many, many other people have had the same experience with leaking heater cores, I would assume the worst. I bought a heater core from Ford ($120 ?), plus the two new hoses ($60 ?), and avoided buying the special Aerostar heater hose removal tool that way.

[link:www.mytoolstore.com/kd/kdspec17.html#3409|http://www.mytoolstore.com/kd/kdspec17.html#3409]

Now that you've flushed the system, be on the watch for leaks or that telltale "sweet" smell inside.

Mine wasn't subtle -- I had steam coming from the vents

c) It's possible that you've got a perforated transmission cooler in the radiator, but I'd expect water mixed with the ATF, and you don't see that, so it's not real likely. Though I do recommend changing the ATF and filter right away -- it's often neglected, and the A4LD needs all the help it can get.

Regards,
Al S.

 

Thanks for the suggestions---looks like someone was trying to plug a leak as I found a hole in the top of the rad. It' s not over-heating now so I am going to wait and see if I can get a good deal on a new rad.
I plan on changing the tranny oil and filter soon and using synthetic oil.
Hope this thing will last me a few years-- my old 87 dodge van 318ci semed to have less problems than this thing but I think its due to the previous owners lack of regular maintenance.

 

>. . . looks like someone was trying
>to plug a leak as I found a hole in the top of the rad. It's
>not over-heating now so I am going to wait and see if I
>can get a good deal on a new rad.

Don't wait for it to overheat! It's too expensive. Yes, our engines are cast iron block/cast iron heads, but the V6 heads tend to crack if overheated (one of mine was cracked, into the exhaust seat area), and the cooling system capacity seems to be quite low -- which gives fast warmup times and good capacity if kept air-free, but little excess capacity if you run low on coolant!

My '89 had an aftermarket copper-core radiator in it when I bought it at 141k -- it had sat dead for a year -- and it began leaking at about 144k. The radiator shop shook their head at it, and refused to recore it, sold me a new conventional (for Aeros) aluminum/plastic radiator. I was sceptical, but it's worked flawlessly for two years. I use quality coolant and distilled water, of course.

>I plan on changing the tranny oil and filter soon and using
>synthetic oil.

&l;"Yes"&r;

Consider adding an inline filter to the trans cooler line -- mine fit fairly well under the A/C compressor area, but my compressor is down under the right cylinder bank. Be certain to use flexible line that is rated for hot ATF -- fuel line won't hold up.

>Hope this thing will last me a few years-- my old 87 dodge
>van 318ci semed to have less problems than this thing but I
>think its due to the previous owners lack of regular
>maintenance.

My aunt has an ex-DEA '86 Dodge 1T window van with so many rows of seats that I can't recall just how many people that bus will hold, and I've been under it quite a bit. The '86 is still carbureted (yours probably had the then-new FI) and the trans lacks OD (I think it was also introduced on that line in '87), but it breaks pretty regularly, everything from the PS gearbox, A/C repairs (every year, and a new compressor about every 2.5 years), innumerable voltage regulators, u-joints, brakes, seat belts break, door latches wear out, etc. They run it pretty hard, though, and in a hot climate. Drives nice (for what it is, a very short schoolbus) but the rear axle whines and it just about can't be parked in a modern parking lot anymore.

She'd like to replace it, but Geez, the cost of replacing it with a new anything is enormous! I think we'll just keep letting it nickel-and-dime us for a while. A new engine looks mighty cheap, compared to an Excursion or whatever.

Regards,
Al S.

 

:-staun
You might want to run more flush through it a number of times and make sure you flush the heater core itself. If you don't, you will constantly have clogged heater core syndrome. Everything that gets mobile inside the system seems to settle in the heater core. This will make your heater ineffective when you really need it.

 

The heater core is pretty much the filter for the cooling system. I'd suggest removing the heater hoses (at the engine) and running the garden hose to it for a while. Do it in both directions. I once got about a quart of sand-like material out of one heater core this way, though the core was out, and I was shaking it like mad while flushing it. The heat really picked up after I put it back in!

(No, it wasn't an Aerostar, but I'm not going to admit, in public, just what cheesy American compact car from the '70s it was.)

Regards,
Al S.

 

I happen to be looking in the Ford shop manual this morning, trying to find a good exploded view of the disassembled nylon/aluminum radiator (the local radiator shop would like a nice exploded view for their lobby), and found this note on flushing the cooling system (pg 03-03-10):
================================================== ======
Heater Core Back-Flushing

All engine cooling system flushing and back-flushing procedures must include a separate back-flushing of the heater core, after the flushing or back-flushing of the engine cooling system. This will prevent engine cooling system particles from clogging the heater core tubes and reducing (or eliminating) coolant flow through the heater core. The heater core must be back-flushed separately from the engine cooling system for proper back-flush water flow direction through the heater core. &l;yup, that's the way that sentence is really worded&r;

&l; . . . &r;

5. Turn the water supply valve on and off several times so that the surge action will help to dislodge larger stubborn particles from the heater core tubes. Allow full water pressure to flow for approximately five minutes.

&l; . . . &r;
================================================== ======

I usually cheat: I connect the garden hose to a heater hose via a spray nozzle that has a on/off handle grip, so I can rapidly turn the water on/off.

Interesting that Ford insists on flushing the heater core separately. I always thought it to be a good practice, but I didn't realize it had become formalized.

Regards,
Al S.

 

Good points Al. Makes one wonder why the cooling system is not provided with a separate, replaceable filter. Air,gas,oil,trans fluid, all are filtered, why not coolant?

 

Such a thing does exist:

[link:neptune.spacebears.com/cars/stories/sctefba.html|http://neptune.spacebears.com/cars/stories/sctefba.html]

I've never installed one, but I've thought about it.

Regards,
Al S.