Changing/flushing antifreeze Lebaron, ''95, 3.0L V6.

Well, I can't believe it but I've forgotten how to change the
anti-freeze. This must be the start of Oldtimers Disease.

It was 70 degrees in Baltimore yesterday, and a good day to flush the
cooling system. Lebaron, ''95, 3.0L V6.

I ran the engine until it was hot or at least warm.

The petcock opens with no tools -- that's nice.

I drained the coolant into one of those rectangular bottles that lie
in their side; I removed the thermostat and flushed for 5 minutes with
a garden hose in the radiator neck until the water ran clear. Let it
drain, put back the petcock, put back the thermostat, filled the
radiator with 50/50, but it took less than a gallon.

Ran the engine a minute or two until I realized that maybe I had only
filled the radiator.

Went to see if I could add more coolant, but I couldn't. Usually I
can keep adding and adding, even when it starts way above empty.

I added about 3 quarts, when the capacity is 8. (That's right, isn't
it?)

After sitting all night, today I could add a 3 or 4 ounces more.

Could it be I never drained the engine after all? How could that be
when I removed the thermostat and the petcock and after flushing let
it sit until nothing was coming out of the petcock hole.?


There's a big chuckhole in the road near here. Maybe I should go
drive over that.

I found a lot of webpages about changing antifreeze, and all but one
said nothing about the thermostat, not even to consider changing the
thermostat when changing the antifreeze. Lots of webpages about
flushing the engine and not a one about removing the thermostat to
help this. Even though one page went into the fact that the
thermostat closes when it's cold. -- They all seemed to talk about
flushing the radiator and not about flushing the engine.


P.S. I also got a Felpro gasket for the thermostat and it has a
brown plastic ring on the inside circumference on one side. But
nothing on the card to say which side of the gasket goes up. Which
does?


Thanks.

mm

 

its always good to change the thermostat every couple years, or if
something's wrong with it. never heard of pulling it to flush. i would
have opened the petcock on the engine block and got the rest of the coolant
out of the engine myself.

 

I don't want to use chemicals, which might cause the radiator to start
leaking again, I just want to use running water to get as much crud
out of the engine and especially the heater core as possible. If the
thermostat is in there, it will be closed because the water from the
garden faucet is cold. Even if I ran hot water from the kitchen sink,
it's only about 140 and the thermostat fully opens at 185, or in my
case, 195.

I don't understand, "got the rest out of the engine myself". Myself?
How?

 

there should be a drain plug or petcock on the block down low on one side or
the other.


they also sell flush kits that you connect into your heater hose to attach
your garden hose, so you can flush the heater core.

 

I see. Thanks. I'll look.

But how come I didn't get most of the fluid out of the block by
removing the radiator petcock. Most of the engine is higher than
that, right, and water seeks its own level. So shouldn't it flow
through the lower radiator hose, into the radiator, and out the
petcock opening? How could it not do that?

That would be good. I'm still looking for the heater hoses! I have a
shop manual around here some place.

Mike

 

On a "normal" engine it would but IIRC on a Mitsubishi 3.0 the water pump is
driven by the timing belt and the lower rad hose goes to a pipe that runs
down the valley between the heads below the intake manifold hence it is up
higher than the block water jackets and would prevent a full drain.

 

"But how come I didn't get most of the fluid out of the block by
removing the radiator petcock."

a lot of times your water jackets in the block sit lower than your water
pump so it will drain down to the level of the water pump/lower radiator
hose and you wont get the rest. it just depends on the block you have and
the drain location.

 

Thanks, Daniel, Rob. I guess I really have to find that manual. I
look whenever I walk around the house, but that's not enough. I'm
going to have to dig. I may have to blast.

 

To fully understand what you both said.

 

Stop a just about any auto parts store and get a
Prestone Flush-n-Fill kit. Permanently nstalls in a few minutes,
use whenever you need a complete flush. This system has been around
for decades. Works well, lasts a long time.
http://www.prestone.com/products/print/461?popup=1

 

Thanks a lot. I'll look into this. The url says it does just what I
want.

 

You are absolutely right.

You were right to begin with and then I found my shop manual, with a
picture!

I ended up prying the heater hose off the engine tube. I used a
ruined phillips head screwdriver that I had sharpened and it worked so
well, it was so easy to get off, even on a 16-year old car, that I
went after the other heater hose that is more hidden but which would
allow a reverse flush.

I had a small brass device, that I bought 40 years ago and had never
used, that was meant to replace the petcock in an all-metal radiator
and connected to a garden hose at the other end. I clamped some
rubber fuel line on the small end and easily forced that about 6
inches into the heater hose. It was a good fit and no water came out,
but brown water came out the other end for a full 5 or more minutes
before it ran clear. I connected the other hose back to then engine
and was able to flush the engine and the radiator at the same time,
with the water coming out the other heater tube from the engine and
the petcock opening. Again it took more than 5 minutes to run clear.

There was no need to drain the engine as long as I could flush it
adequately.

I certainly wasn't going to take out a freeze plug, or whatever that
would be, and then try to replace it properly, so it woudn't leak,
outside in February, with or without a lift, and it wasnt' necessary.

To refill, I removed the thermostat housing and also added via the
radiator -- neither alone was enough -- and I got a whole gallon of
anti-freeze in, and much less than a gallon of added water.


And best of all, the heater works as well as ever now, putting out hot
air when the temp gauge is a full mark short of the max value that it
reaches. When last month it only put out slightly warm air at most.

The air is still not as hot and there's not nearly as much of it as
with my full-size Pontiac and Buick convertibles were, but they had
318, 359, and 400 CID engines. The engine on this car doesn't even
get hot enough to melt the snow on the hood. (Although I just noticed
that a friend's small size Nissan pickup had a hot hood 5 minutes
after turning off the engine. I thought maybe no cars generated so
much excess heat since the engine mileage laws.)


I saw the the Prestone device at the store and the pictures made it
much more understandable than the webpage QX gave me (which had no
pictures or drawings! It would be very good on any car it would fit,
but there just wasnt' space to connect it here.

Tbanks to all of you, and thanks to you, Paul.