1995 Honda Accord boils over

I nominate the anything with the Subaru 2.5L and Renault turbos.

 

How about the front of the water pump? Viscous fan clutches were very
popular in the '80s. They worked pretty well when new, but the silicone
tended to leak out over the years. They would become progressively less
effective and the driver wouldn't know until the situation got really bad.

Mike

 

DING! DING! Mike wins the prize! Exactly what happened in my Supra.

I have the records from the old owner. She spent $1100 traking down an
overheating problem.

The first year I had the car, the temp barely got over 90 degrees all
summer. Plus, we did a timing belt and the car had all new coolant in it.
It never overheated.

Last summer, we had a lot of days over 90 degrees, and it was on these
days it was most likely to overheat. I asked the guys in the Toyota forum
and a former Service Rep gave me a method for checking the fan (basically,
get the car up to temp, stop the engine and try to spin the fan...mine
spun with no resistance at all.)

New fan clutch, no overheating! I did notice the previous owner did not
install a new clutch...

 

Check my response to Mike, above.

I was also running without the shroud underneath the engine, and while
replacing it helped somewhat, it wasn't until I replaced the clutch that
the problem disappeared.

 

When they designed the car, asbestos HGs were still in use. When building
started, asbestos HGs were gone. I guess they went to a semi-metallic HG,
which called for higher torque on the head bolts. Toyota *didn't* call for
higher torque, and suffered a lot of BHGs.

Luckily, whoever had the car originally either had the head retorqued, or
replaced the gasket and had it torqued to the new spec.

 

I used to work for a guy that sold used Fords. We sold a lot of Taurus',
but RARELY one with a 3.8. He *knew* better!

I was working at a CarQuest, and we had a small market across from us. A
guy stopped with a Continental to get a paper and a cup of coffee. It was
Feb, so he left the motor running.

Normal...a little steam..then a puff...and another puff...and a few more
puffs...by the time the guy came out of the store there was a steady
stream of steam flowing from the tailpipe. He stopped someone passing,
pointed to the tailpipe, and the other guy just shrugged his shoulders and
walked on. Before I could get to the door, the guy drove off.

Sure hope he went RIGHT to the Ford dealer down the street!

 

that's not "old", it's simply designing the heat dumper to match the
heat generator. with an electric radiator fan, no healthy car will use
anything other than airflow cooling on the freeway.

 

around town, sure. but not on the freeway. lack of shroud, insect
debris blockage, kinked coolant pipe, slipping belt on coolant pump, out
of spec thermostat - these all have much more effect at freeway speed.

 

Autos use electric fans purposely so they don't have to draw engine power
to turn the radiator fan when it's not needed;when the vehicle is at speed
and there's plenty of natural airflow.

The old belt driven fans changed to plastic blades because they could
flatten out at higher speeds and draw less power from the motor.
Electric fans were just the next step after that for economy.

 

by "flatten out" do you mean a variable pitch fan blade? that's
somewhat exotic and rather expensive. what used them?

 

My Supra has one. Also a Celica I had ('85) and an '85 Corolla.

Most of the fans post 75 or so are plastic, one reason being weight and
the other being the flexability of plastic. I can't remember the last time
I saw a metal fan!

 

just because it's plastic does not mean it's flexible enough to "flatten
out" as if it's variable pitch. what mechanical properties do /you/
think "flexibility" gives the fan?

 

I don't know whether they were ever used as OEM fans, but my motorhead
brother was pretty fond of aftermarket "flex fans." If the plastic blade is
mounted to the hub by the leading edge, it's a good bet it is a flex fan. If
the blade is mounted by the whole root it is just another fan.

Mike

 

interesting - i've never seen a fan like that. seems kind of bizarre to
me since i can't see what would keep the blade pitched to improve
airflow when it was supposed to be working, but hey...

indeed.

 

Who cares?

 

you should if you want the fan to move the freakin' air that you think
is cooling your engine!!! if the blades can adopt a position of least
resistance, they will. that means throughput will be minimal - totally
defeats their supposed purpose.

 

http://www.flex-a-lite.com/auto/html/7-blade-flex.html

 

did you know that the outer extremity of a fan blade moves faster than
the bit nearest the hub? apparently these guys don't since it's the
same pitch for the whole blade!!! what a total p.o.s.

 

I would be inclined to think that these fans could actually inhibit
cooling during high speed driving as the "flattened" fan blades would
act muck like a feathered prop in the wrong position which then enters a
windmilling mode.

I never had any confidence in these "devices."

JT