94 civic overheating saga...continues

Still overheating. They replaced radiator saying it was clogged. Still no
joy.

Now saying head gasket.

Any guesses on what I'm looking at for a head gasket replacement?

G-Man

 

===========================

Is the radiator and reservoir maintaining their levels of coolant?

Are the radiator fans ever coming on.

If your head gasket is shot, there could be coolant in the oil, white
clouds of smoke / steam coming out the tailpipe, and /or oil in the
coolant.

Above all, make sure your son keeps the cooling system topped up
correctly.

Also, please tell us the symptoms of 'overheating'.

'Curly'

 

It climbs to the RED, the coolant catch tank is bubbling coolant over. It
doesn't seem to pull the coolant from the catch tank.

Fan only comes on when it's amlost in the red. Okay, probably touching the
red. We keep topping it off. It keeps spitting it out. Fan pulls the temp
back down, but doesn't kick on again until red.

No exhaust smoke or strangeness in the oil as far as what is on the
dipstick.

The coolant in the catch tank seems clean.

Both hoses top/bottom are hot.

 

I have a similar problem with my 87 Prelude! The dealer said to replace the
timing belt and the water pump. It is not time to replace the timing belt.
The water pump has never been replaced but it seems to work fine!!! Mine
goes to about 80% but never to the red. It usually happens when idling in
traffic. The fan used to come up at 50% and turn on after I shut down the
engine. But now it come on at 80%. I have one eye on traffic another on
the gages!!! I replaced the fan switch but that did not help!!!!!

 

You said you replaced the fan switch. You mean the thermal switch that is
in with the thermostat? That would be what is controlling the temp that it
comes on at. It's a cheap item, I'd start there. I'm still going to
replace my thermal switch even if it needs a head gasket as I want it to
come on before the RED.

G-Man

 

========================

I think we're finally getting somewhere... Your system isn't building
pressure, so you may just need a new rad cap. That's probably why it's
not pulling the coolant back in either.

A presurized system boils at a much higher temp, and having steam inside
your system throws off the fan switch and the thermostat (both must be
emmersed to work, just like an emmersion thermometer) Even your temp
gauge won't read correctly if your coolant is boiling. . .

'Curly'

===============

 

With the engine coolant cool, open radiator cap and look at the
coolant, is it green or gray? Oil in the coolant turns the coolant to
gray. Run the engine and look for air bubbles...a cracked block or
blown head gasket can blow air into the coolant....I am talking about
below boiling temperature. Is there an air vent valve to bleed the air
out of the coolant on the high point of the engine? If so bleed the
air out of the coolant.

 

Replaced cap (sorry, left that out).

Coolant is a nice green.

Will check the air blowing in the radiator today.

 

I think the fan switch is located under the radiator. I do not know where
the thermostat is located in 87 prelude SI but that is my next step.

 

Check EVERYTHING else before you do the head gasket. This was
happening to my car and I spent $900 for head gasket/thermostat and
that didn't fix the problem. Obviously, it's something cheaper.

John

 

The fan switch(engine coolant temp sensor) on my 94 Integra GSR is on the
thermostat housing,close to the engine.

 

Sorry to say this, but the head gasket should be the very last thing to
replace when trying to fix a car when there isn't a clear evidence
that's where the fault is. I used to have an old 86 Camry that would
overheat in the same circumstances, and when I took it to Canadian Tire
the first thing they wanted to do was replace the head gasket for
CAD$1500 (CAD$1=US75c). It turned out to be a clogged, leaky radiator
which only cost me CAD$200 for a new one, including installation.

In the worst case scenario when avoiding changing the head gasket you'll
replace other minor components that probably needed replacement anyway.

Cosmin

 

Can you tell if anti freeze is in the oil?

It could be the water pump. a water pump can
break without totally failing, seizing, or leaking.
If the impellers are worn badly, the water does not
go through good. i have had this happen on
a mustang. when i took the water pump off my
crx, it was still going, but man, it was worn inside
almost to nothing.
If it is your head, there should be white yuck in
your oil. Obviously you already replaced the
thermostat (?)

 

Yes, replaced the thermostat. Oil was dirty on the stick, but nothing
unusual. Water Pump replaced along with Timing Belt last November. Only 3k
on it.

G-Man

 

Did this problem by any chance start right after the timing belt
replacement? Timing could be off by one belt tooth & that would be enough
to cause overheating.

 

That was replaced last November. Been good 'till now.

G-Man

 

Have you checked for collapsed hose when running?
Have a radiatior service center look at it, and have a pressure test
done on the radiator system. If it doesnt hold pressure you have the
answer usually. Head gasket MUST be replaced using an original HONDA
gasket or it can happen again, sooner than needed. Replace the full kit
as supplied. It allows a better job. I know i did and the bits i
replaced were all in need of replacement and supplied by the kit.

 

Could well be a head gasket. You won't be the only one on this model.
It's a vicious circle: overheating causes head warping causes head
gasket losing seal causes overheating.
Gasket replacement itself isn't horribly expensive, if the car is
worth keeping, maybe $350?
But it's the possible incidentals; if head is warped from overheating
or just naturally, new gasket will go out like old did within a while.
Besides, after this age, the car might want a new head, so you'd need
to look at the valves from inside once you get the head off, or just
bite the bullet and decide in advance. Head from Honda is ridiculously
expensive, rebuilt heads from places much cheaper, maybe $250 and up,
you can get them all built up with valves and stuff. Do a search.
Decide whether you need to replace the cams or not. Is it VTEC? More
cams. It can be iffy using an older cam with new hardware; the cam
lobe and the pieces that rub on them wear to fit each other like an
old married couple, and replacing one of them and not the other can
cause rapid wearing out. Or if the head is generally OK, you might
want to just replace the valve seals while the head is out, that's not
too bad and they wear out, and it's easier than doing it on an
assembled engine in a couple of years.
Another hassle: warranty. As mentioned above, they can botch a head
replacement or head gasket replacement, and it won't blow for a while.
On the other hand, the mechanic doesn't want to be on the hook if you
overheat it next summer and warp the head again. On top of which, if
it's a rebuilt head, if the rebuilder isn't very careful in cleaning
out metal chips etc. from cooling and especially oil passages,
obviously there will be trouble. A lot of engines that really
physically blow up; throw a con rod, etc., have had recent overhauls,
rebuilt heads, etc. (including one I bought once) so that's a sign to
be wary. On the other hand, the last head I bought built up, street
performance wise, was from PAECO automotive in GA, and it was just
beautiful, and so clean you could eat off it, etc. They've been doing
compact/import performance since forever, not just the current craze.
Hot rod Pintos, etc. Allocate maybe $500 for an average rebuilt head
swap.
Of course, you can shop around for a new engine, if you live somewhere
where people are swapping in the DOHC b16A engines to replace the
stock SOHC ones, you can often get the old takeout SOHC for as low as
$50 if you haul it away. Labor to swap isn't a hell of a lot more than
the head work, say $500, and since you're not messing with the head
replacement, either the engine will work when it's in or it won't,
length of warranty coverage isn't such an issue. Of course, you are
reasonably likely to get something that has problems too so you
definitely want some coverage. Or you can join the fun and get a DOHC
yourself and swap it in.

 

That's standard mechanical practice, for pretty much any repair start
at the most expensive end. Mechanics don't want to start out by
replacing the thermostat for $50 and it doesn't work, so they end up
swapping the head for free as warranty on their repair, and it costs
them $900; they'd rather swap the head and have you pay $900, and if
that doesn't work they'll replace the thermostat and eat the $50.