1995 Honda Accord boils over

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

snipped-for-privacy@wt.net wrote in news: snipped-for-privacy@c35g2000hsg.googlegroups.com:

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.

snip

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

Grumpy AuContraire wrote in news:VGKZh.94257$ snipped-for-privacy@bgtnsc05-news.ops.worldnet.att.net:

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!

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