1995 Honda Accord boils over

My daughter owns a 1995 Accord with about 125K on it and a new timing
belt and water pump. The car was running fine for several months after
purchase when it suddenly got hot and boiled over. She had the
thermostat replaced and that wasn't the issue. Here's what I know: It
starts and runs normally, it heats up to normal operating temperature
at idle and will happily stay there all day. With the cap off, the
water level will come up and overflow the filler neck and if i
accelerate the engine, the water will pull out of the neck into the
system. Water does seem to move through the system and with the heater
on, I get heat in the cab...lots of it. With the heater off and full
cold with A/C on, temp remains the same and the cooling fans come on.
The fans will run after I shut it off. If I drive it a short distance
it is happy enough but (if the car is warmed up) after about 1/2 a
mile, the gauge will jump to the halfway point and then climb. I can
turn the heater on full bore and get it to cool some but it won't be
happy for long. If I pull over and let it idle, it returns to normal
temp.
I have bled the system according to the Service Manual for the car. I
have verified as best I can that there are no holes in the system and
I see no leaks.
When the engine warmed up, it looked like it was burping some air out,
but the bubbles were random and they were not smoky. I see no steady
stream of bubbles in the coolant as it passes through the radiator,
but when the system is closed and it gets warm the behavior is that of
an old car boiling over. There is a lot of action in the overflow tank
and it begins to fill and bubble violently.
I am out of options. I am getting conflicting symptoms as to whether
or not it is a failed head gasket and I am not sure if the cooling
fans are working while it is just running down the road since my wife
won't let me strap one of my boys to the hood while I drive it to look
and listen.
Any suggestions would be greatly appreciated.

 

if there's bubbling in the expansion bottle, it's head gasket. for
sure. unless you do the job yourself, and know what you're doing, price
out the options between having it repaired and simply replacing the
motor with a jdm import. they're surprisingly cheap and labor to
replace is substantially less than a gasket job and all the labor involved.

 

Sounds like you need a new radiator to me..
I'm not so sure about the head gasket..
Maybe, but I still think your radiator is about
shot. A leaky head gasket will not cause all
the symtoms you have. IE: overheating...
The only way a head gasket causes overheating
is when it finally loses it's coolant.. If it's still fairly
full when doing this, I doubt the gasket is the problem.
Most of your problems sound like a bad radiator.
Thats why it overheated in the first place I bet.
MK

 

A fairly common symptom of head gasket trouble is wild fluctuation of engine
temp. I don't know why that is, but it's seen all the time. I rely pretty
heavily on the shadetree test for head gasket trouble: with the engine cold,
remove the radiator cap. Start the engine and pinch off the tube from the
radiator neck to the reservoir. Place the palm of the other hand over the
radiator neck for a few seconds. If you feel a steadily rising pressure or
(worse) fluctuations as the engine turns, the head gasket is very likely
bad. This test has some false negatives - the head gasket may not leak when
cold idling - but I haven't seen a false positive. The most widely accepted
test is a chemical test for combustion products in the coolant.

I often focus my attention in overheating cases based on the way the system
behaves. Bad radiators usually show up as a slow buildup of heat that never
wants to go away. Air flow or water flow problems show up at idle but the
temperature drops rapidly when the car gets moving; water flow problems
return to normal within seconds while air flow problems take a minute or
two.

It really doesn't matter if the fans are running while driving; air flow
should be fine then. I hate to say it, but I fear for your head gasket at
this stage. Overheating while going down the road and cooling down when you
pull over and idle make that a prime suspect.

Mike

 

wrote in

bubbles in the coolant reduces it's heat carrying ability.

 

Radiator my be irreversibly clogged and need to be replaced.
I havd to do it once after about 150K miles.

 

Not necessarily. When the coolant overheats it boils. Since it is a closed
system, the only place it can boil is...in the bottle.

Last summer my Supra (the Poster Child for bad head gaskets!) boiled over
a couple of times. The first time was scary as hell! On the highway, temp
gauge rising, a loud *SIGH* from under the hood and smoke kind of smoke! I
still have NO idea what the smoke was! Opened the hood and the Overflow
bottle was bubbling like a witch's cauldron! I let it cool and it ran fine
for a few weeks.

Then, we were on our way to a gig in Vermont and it started overheating
again. This time I was keeping an eye on the termp gauge and pulled over
well before it sighed again. But the OF bottle was bubbling up again.We
got to the place just as the temp was creeping up again.

In the next week I ran some tests and determined the fan clutch was shot,
and on hot days there just wasn't enough air getting into the engine bay.
I put in a new fan clutch (this was in late June, BTW) and I haven't had a
problem since. No coolant disappearing, no boil overs, no overheating.

I consider myself LUCKY! (Knocking on my Pine desk!!!)

 

that's supposition, not fact. run an infrared thermometer on the
cooling system. check out the temperature delta between the main system
and the expansion bottle on the end of the long skinny pipe. the only
way for there to be gas bubbling in that bottle simply from "boiling" is
if the vent on the radiator cap is stuck, /and/ the engine reaches way
past boiling, /and/ this cap suddenly releases allowing sufficient
superheated water to exit the long skinny pipe still at above boiling,
and for that to heat and keep on heating the cooler liquid in the
expansion bottle. it /can/ happen, but it's highly unlikely.

the fans don't work on the highway - airflow from car movement exceeds
airflow from fan rotation by a country mile. if you were boiling, you
had airflow restriction, thermostat problems or a gasket problem.

buy an infrared thermometer and scope the temp of the block.

gaskets can be odd. i boiled mine with a leaking gasket a couple of
summers ago. then she settled down, then she stated leaking again. and
i ran it leaking for about 10k miles before i decided it was bad enough
to fix.

you [and the op] should do an exhaust gas chemical test on the coolant -
that'll show for sure.

 

LOL! You come to Mass on a hot July day, and I'll take you for a ride. At
70MPH on the highway, when the fan kicks in it sounds like a B-17 trying
to pass you! Oh, yeah, the fan kicks in! (It's attached to the
crankshaft...not electric, and uses a heat-sensitive oil that thickens
when hot and causes the fan to be driven, rather than just 'feathering'.)

 

it comes on because it's just a "dumb" thermostat control, but it
doesnt' mean it's contributing very much. how much additional airflow
do you think is generated by 1 sq ft of fan vs 70mph on the full rad?
if it's even 10% i'll be amazed.

 

This is new to me... A fan attached to the crankshaft??? What is this
vehicle?

That said, if you're going 70 mph and it (thermostatic clutch) causes
the fan to come on, most likely you either have too little radiator or
its plugged.

JT

 

Not a Honda.

No kidding.When the thermostat on my Integra stuck open,just going 20 mph
would cool the motor down to the C line(well below normal),In hot Central
Florida,in the summer.

 

....which is a whole lot better than it stickin' closed!

<G>

JT

 

I may be showing my age...I'm not sure if it's actually on the
crankshaft...(I'm sure it's not...)

Everything seems OK, but the previous owner sunk $1100 into the cooling
system...

 

Brings the temp down on the gauge, keeps the car from overheating. I'd
say, enough!

 

It was late...you know, not electric...at the front of the engine...Old
School...

'88 Supra...the Poster Child for Blown Head Gaskets...

 

I know that version of Supra had head gasket issues. But surely the real
poster child for blown head gaskets would be a Dodge Neon, wouldn't it?

 

doesn't mean they knew what they were doing. i knew a guy spend
thousands on "cooling problems" for a rear engine, front radiator car he
was trying to race. constant overheating. he, and a number of other
"race mechanics" failed to see the significance of a 3/4" home-built
water manifold bolted onto where the thermostat was supposed to be.
whoda thunk to consider effect of such a small pipe on coolant flow!!!

bottom line, these vehicles ship from factory having been tested at full
throttle, fully loaded, in summer, in death valley. if yours is
overheating just tooling along the highway without aftermarket
assistance, there's something wrong. and it's not the fan.

 

Or Taurus' with the 3.8 engine. I can tell a long tale of woe regarding
one of those POS...

JT

 

About thirty years ago while returning home from a car show with my 1956
Studebaker Hawk, the temperature gauge began to rise. I pulled over and
saw that the fan belt had "disappeared." At any rate, the rest of the
drive was on a freeway and I surmised that I could get home since the
incoming air would drive the water pump as well as cool the radiator so
long as I kept up a reasonable speed. The gauge never went above 180°.

Sometimes, "old" can be better...

JT