1994 Miata Overheating

I left my car at my son's for a month and unknown to me his wife's
grandfather had removed the radiator cap and not put it back on
correctly. About 30 miles down the interstate I noticed the spray on
the windshield and my temp gauge which always runs right under the
halfway mark was on H.
I pulled over. Let it cool about an hour. Added water and went to the
next exit. It ran right where it had but started a little rough.
Before I left the parking lot it went to H and I rolled back and
parked it. The friend I called tried to drive it but it went back to H
and he heard a pop. When we opened the hood steam was coming from
under the top ledge of the radiator. I'm a single woman, it's parked
right now in a lot. I'm not sure what direction to turn. It's in an
area I don't know any mechanics in. If I start calling as a female
from out of the area I can already hear the cash register going ching
ching. Some background info may help me become knowledgeable enough.
HELP please!

wrote:
> I left my car at my son's for a month and unknown to me his wife's
> grandfather had removed the radiator cap and not put it back on
> correctly. About 30 miles down the interstate I noticed the spray on
> the windshield and my temp gauge which always runs right under the
> halfway mark was on H.

Is the radiator original?

> I pulled over. Let it cool about an hour. Added water and went to the
> next exit. It ran right where it had but started a little rough.

This is where we hope that it did not warp the head. Is there any sign
of oil in the water or water/antifreeze in the oil dipstick?

> Before I left the parking lot it went to H and I rolled back and
> parked it. The friend I called tried to drive it but it went back to H
> and he heard a pop. When we opened the hood steam was coming from
> under the top ledge of the radiator. I'm a single woman, it's parked
> right now in a lot. I'm not sure what direction to turn. It's in an
> area I don't know any mechanics in. If I start calling as a female
> from out of the area I can already hear the cash register going ching
> ching. Some background info may help me become knowledgeable enough.
> HELP please!

The original problem is obvious, no cap pressure.

The extra heat may have fried your thermostat, or more likely, cracked
your radiator, especially if it is original, in which case it was
probably going to break before long anyway.

When your friend tried the second time, did it overheat almost
immediately or take a few minutes?
Also, did it drop a large amount of antifreeze/water on the ground or is
there still some that you can see from the cap opening?

My first checks would be to see if the radiator is cracked, which will
probably be visible on the upper plastic section.
Then check the coolant level and look for signs of oil, and check the
oil for signs of antifreeze.

I am sure that others here can offer additional help, but you may want
to try the miata.net forum as well if you have not already. It is a lot
more active than this newsgroup.

Good luck!

Pat

wrote:
>
> I left my car at my son's for a month and unknown to me his wife's
> grandfather had removed the radiator cap and not put it back on
> correctly. About 30 miles down the interstate I noticed the spray on
> the windshield and my temp gauge which always runs right under the
> halfway mark was on H.
> I pulled over. Let it cool about an hour. Added water and went to the
> next exit. It ran right where it had but started a little rough.
> Before I left the parking lot it went to H and I rolled back and
> parked it. The friend I called tried to drive it but it went back to H
> and he heard a pop. When we opened the hood steam was coming from
> under the top ledge of the radiator. I'm a single woman, it's parked
> right now in a lot. I'm not sure what direction to turn. It's in an
> area I don't know any mechanics in. If I start calling as a female
> from out of the area I can already hear the cash register going ching
> ching. Some background info may help me become knowledgeable enough.
> HELP please!

What you are hoping for is that you noticed the overheating soon enough
that you didn't also blow your head gasket. That's a much more
expensive repair than just the radiator. But first of all you
definitely blew out your radiator, and you'll have to get that replaced.
If you ask the dealership they'll quote you something like $400 for a
new OEM radiator. Don't buy that; you can get an aftermarket
replacement from any number of parts outlets for about $150. It's not a
real elaborate job to pull the old one and put in the new; I wouldn't
expect to pay more than about $125 for labor. Good luck!

Yours WDK -

On Jul 5, 11:44 am, pws > wrote:
> wrote:
> > I left my car at my son's for a month and unknown to me his wife's
> > grandfather had removed the radiator cap and not put it back on
> > correctly. About 30 miles down the interstate I noticed the spray on
> > the windshield and my temp gauge which always runs right under the
> > halfway mark was on H.
>
> Is the radiator original?
>
> > I pulled over. Let it cool about an hour. Added water and went to the
> > next exit. It ran right where it had but started a little rough.
>
> This is where we hope that it did not warp the head. Is there any sign
> of oil in the water or water/antifreeze in the oil dipstick?
>
> > Before I left the parking lot it went to H and I rolled back and
> > parked it. The friend I called tried to drive it but it went back to H
> > and he heard a pop. When we opened the hood steam was coming from
> > under the top ledge of the radiator. I'm a single woman, it's parked
> > right now in a lot. I'm not sure what direction to turn. It's in an
> > area I don't know any mechanics in. If I start calling as a female
> > from out of the area I can already hear the cash register going ching
> > ching. Some background info may help me become knowledgeable enough.
> > HELP please!
>
> The original problem is obvious, no cap pressure.
>
> The extra heat may have fried your thermostat, or more likely, cracked
> your radiator, especially if it is original, in which case it was
> probably going to break before long anyway.
>
> When your friend tried the second time, did it overheat almost
> immediately or take a few minutes?
> Also, did it drop a large amount of antifreeze/water on the ground or is
> there still some that you can see from the cap opening?
>
> My first checks would be to see if the radiator is cracked, which will
> probably be visible on the upper plastic section.
> Then check the coolant level and look for signs of oil, and check the
> oil for signs of antifreeze.
>
> I am sure that others here can offer additional help, but you may want
> to try the miata.net forum as well if you have not already. It is a lot
> more active than this newsgroup.
>
> Good luck!
>
> Pat

Thank you for your reply. Yes it was the original radiator. The car is
being towed to me Monday and then probably on to a mechanic. From my
discussions with a couple mechanics I'm afraid there is engine damage
due to it not wanting to idle on it's own after putting the cap back
on. I am hoping for the best and the 1st thing I will do before
sending it on is check for water in the oil and vice versa. Several
friends have suggested I suck it up and send her to a junkyard, they
just don't know, lol.

On Jul 5, 12:11 pm, "W. Kiernan" > wrote:
> wrote:
>
> >
> > I left my car at my son's for a month and unknown to me his wife's
> > grandfather had removed the radiator cap and not put it back on
> > correctly. About 30 miles down the interstate I noticed the spray on
> > the windshield and my temp gauge which always runs right under the
> > halfway mark was on H.
> > I pulled over. Let it cool about an hour. Added water and went to the
> > next exit. It ran right where it had but started a little rough.
> > Before I left the parking lot it went to H and I rolled back and
> > parked it. The friend I called tried to drive it but it went back to H
> > and he heard a pop. When we opened the hood steam was coming from
> > under the top ledge of the radiator. I'm a single woman, it's parked
> > right now in a lot. I'm not sure what direction to turn. It's in an
> > area I don't know any mechanics in. If I start calling as a female
> > from out of the area I can already hear the cash register going ching
> > ching. Some background info may help me become knowledgeable enough.
> > HELP please!
>
> What you are hoping for is that you noticed the overheating soon enough
> that you didn't also blow your head gasket. That's a much more
> expensive repair than just the radiator. But first of all you
> definitely blew out your radiator, and you'll have to get that replaced.
> If you ask the dealership they'll quote you something like $400 for a
> new OEM radiator. Don't buy that; you can get an aftermarket
> replacement from any number of parts outlets for about $150. It's not a
> real elaborate job to pull the old one and put in the new; I wouldn't
> expect to pay more than about $125 for labor. Good luck!
>
> Yours WDK -

Thank you especially for the aftermarket info. It will be towed home
Monday and then on to a shop after I check a few things. Worried but
hopeful.......

On Jul 9, 12:37 am, wrote:
> On Jul 5, 12:11 pm, "W. Kiernan" > wrote:
>
>
>
> > wrote:
>
> > > I left my car at my son's for a month and unknown to me his wife's
> > > grandfather had removed the radiator cap and not put it back on
> > > correctly. About 30 miles down the interstate I noticed the spray on
> > > the windshield and my temp gauge which always runs right under the
> > > halfway mark was on H.
> > > I pulled over. Let it cool about an hour. Added water and went to the
> > > next exit. It ran right where it had but started a little rough.
> > > Before I left the parking lot it went to H and I rolled back and
> > > parked it. The friend I called tried to drive it but it went back to H
> > > and he heard a pop. When we opened the hood steam was coming from
> > > under the top ledge of the radiator. I'm a single woman, it's parked
> > > right now in a lot. I'm not sure what direction to turn. It's in an
> > > area I don't know any mechanics in. If I start calling as a female
> > > from out of the area I can already hear the cash register going ching
> > > ching. Some background info may help me become knowledgeable enough.
> > > HELP please!
>
> > What you are hoping for is that you noticed the overheating soon enough
> > that you didn't also blow your head gasket. That's a much more
> > expensive repair than just the radiator. But first of all you
> > definitely blew out your radiator, and you'll have to get that replaced.
> > If you ask the dealership they'll quote you something like $400 for a
> > new OEM radiator. Don't buy that; you can get an aftermarket
> > replacement from any number of parts outlets for about $150. It's not a
> > real elaborate job to pull the old one and put in the new; I wouldn't
> > expect to pay more than about $125 for labor. Good luck!
>
> > Yours WDK -
>
> Thank you especially for the aftermarket info. It will be towed home
> Monday and then on to a shop after I check a few things. Worried but
> hopeful.......

It's hard to say that there's so much wrong, as the other fellows have
pointed out. The part that worries me is that you added water then
tried to drive away...If you were evaporating enough coolant to
overheat the engine (which I have before!) then it takes a good hour
of slowly pouring in mixed coolant directly into the radiator for the
radiator, the cooling pipes, and coolant reservoir to fill up
completely.

One pours it slowly into a hot engine, because cooling it too quickly
might crack the block. You might call that an undesirable effect.
The reason you keep doing it over an hour is to give the coolant time
to work itself into the whole system.

While pouring into the radiator...the car should be on. This means
the fan is running and so is the pump...with the vibration of the car
as well as the help from the pump, the air that you discovered does
not circulate heat very well will be pushed up and out of the top of
the rad.

I'm pretty paranoid about all of this, so I keep jumping into the
driver's seat to check the temperature. If it gets to a little less
than 7/8 of the gauge, I shut the thing down and wait for it to cool
itself enough to pour again.

I know I'm done when the coolant is visible from the rad cap hole, it
doesn't sink, and the temp is back where it should be. That's all
assuming the rad doesn't have a leak, the thermostat is in working
condition, etc. :-P (With the rad leak you probably have, I wouldn't
change my prognosis, though.)

The worst thing you might have done is blow your head gasket. This
sucks, but it's not...all that terrible. You probably did blow a seal
on your stock radiator, though. Depending on the age, it was probably
almost time to replace it anyways. Is your car a 97 or earlier?
Then, it's time. I recommend Radiator Barn online for the rad. They
have great prices, super-friendly service, and the radiator...well, I
forgot I installed it! That's a good sign. If you drive a standard,
it's okay to get a radiator for the same year for an automatic. They
have a higher water capacity, which will make you a bit safer, though
it will make the nose around 4-8# heavier.

Hope I could help you, or at least anyone else reading this.
Overheating sucks. I've been the one to "make it work" on my own
Miata, my sister's old Civic (twice), my friend's car, and given
advice on it to many others. It's just, no fun at all.

Best of luck,
-r0ll