where is the thermostat?

Where is the cooling system thermostat located in an 87 prelude? Can it
be replaced in my garage or do I need to take it to the dealer? Please
email a picture, if available.

 

They're usually in the housing where the upper rad hose connects to
the block.

They are easy to replace if the screws can be undone, but often
they're rusted solid and tend to break, especially on something that
old.

 

Follow BOTH rad hoses to the block. The one with the largest casting at the
end is the one with the thermostat.

A lot of cars these days (including the B-series engines and several
Toyotas) have the thermostat at the engine end of the LOWER rad hose.

A major bitch, that. Start thinking about removing anough stuff to get a
drill in there to get rid of the broken piece. And drilling a hard steel
bolt out of a soft aluminum block is not fun.

 

Yep, I just put a thermostat in my new '86 Prelude... It actually didn't
have one in it when I got it. Two bolts. Remove the upper radiator hose from
the engine. Then remove the two bolts holding the outlet for the hose to the
block and remove the outlet. Replace the thermostat, put it back together,
and top off your coolant. It sure is nice to have heat... Not to mention a
car that doesn't take 15-20 minutes to warm up and even then only stays at
the edge of the normal range when you're moving.

Something that old? LOL I'm used to working on '60s Fords and I've never had
a single thermostat housing bolt snap. Hell, I've even been lucky enough to
never snap an exhaust manifold bolt (or any bolt for that matter), though I
did once round off an exhaust manifold bolt head pretty well. I gave up and
whacked it with a hammer real hard a few times which thankfully loosened it
up enough to get off with some pliers and a lot of muscle. Anyway, an '87
model year car is not old, it is modern and fairly new. It's only 16 years
old.

Now the thing I don't get is all this metric stuff... I haven't a clue what
a millimeter looks like so it takes me a while tog et the right socket,
whereas on my Fords I pretty much know the size of every nut and bolt, and
the ones I don't I can eyeball and normally get the rgiht size. It's also
nice to have room to work. I've gotta change the alternator and smog pump
belts as they squeel when it's cold. I've been putting that off for a while
now as this sub-subcompact is FWD so it's got a transverse mounted engine
and it doesn't seem like there is much room to work in. I think when I
change the belts I may just leave the smog pump belt off depending on how
hard it feels to turn... The increase in mileage ought to do me well.
Overall I'm very dissapointed with the mileage I've been getting. When
correcting for the error in the speedometer/odometer I'm only getting ~28-29
MPG. I was hoping for more from a sub-subcompact 4 banger with a manual
overdrive transmission. Oh well, I can't complain for $300 though.

 

I snapped the head right off of the bolt in the thermostat housing in my 87
Accord.
I had to drill it out, slightly damaging the housing, but I went to a Honda
dealer, bought a new bolt, and it had enough bite to do the trick.

I can safely say that over 90% of the bolts in my car are rusted/corroded so
that great care is required to remove them without snapping the head off, or
rounding off the head.
I live in Boston...and my Accord was originally bought in Chicago.

I imagine you live somewhere that rust isn't as big an issue as it is here.


--Peter

 

Yeah, but where are you? And where is he?

Let me guess, you don't drive on the salt-laden roads of the
north-east...?

 

Actually I'm in NJ... They salt way too much here. We get some pretty harsh
winters here, had a nastly 'blizzard' last year. In NJ though they go crazy
and everything shuts down with anything more than a few inches of snow. Then
they go crazy with salt, like you wouldn't imagine. For most of the winter
we would be better off without any plows, but in areas that honestly need
plowing just plut sand at intersections (NOT SALT). I was always wiping salt
off my Fords in the winter, trying to keep the salt from rotting them away.

A bunch of sissys I tell ya! I was born in Michigan, but moved to NJ when I
was still a baby, so maybe I've still got some Michigan winters in my blood.
This will be my first winter driving in anything other than my '67 or '68
Galaxie 500 so I'm a bit nervous. My old Fords had tons of ground clearance
and a good amount of weight on the tires. This Prelude is a sub-subcompact
that is barely above the ground and has no weight to it. Anything more than
2 inches of snow and it probably won't budge. It's a nice little car, and I
definitely appreciate getting more than 14-16 MPG, even if it isn't all I
had hoped for. I'll tell you though, it's an eternal struggle to get out of
that car what with being 6'3.5". For $300 I couldn't resist, it's been a
great little beater the past couple weeks, and even fun to drive with the
dual carbs and 5 speed. I'm gonna see if I can't get rid of some of the rust
starting aroudn teh wheel wells and doors before the snow/salt comes... Try
to keep it from rotting away as I hear these Hondas have a big problem with
that.

 

Also... It took me about 10 minutes to do, if that. I noticed this little
Honda has a clever bleeder valve like the type on wheel cylinders to bleed
air out of the coolant system at the highest point right behind the
thermostat. That is a clever idea... Like the defrosters for the side
windows [that don't work very well]. The windows in my Prelude fog up like
mad. I think it's because tehre is no room inside the car that my breathing
fogs it up so fast... I've never had windows fog up like that before.
hopefully with the new thermostat the side defrosters will work a little
better.

Cory

 

Cory,

Fogging windows (a la Hyundai Pony) is a sign that your heating control
is set to (or stuck on) 'recirculate'. Your description gave away the
answer:

In winter, outside air is bone dry, but the air inside is wet due to
breathing, snow on floor mats, etc. If you turn off the recirculator
you'll see your sauna bath problems disapear . . .

'Curly'

--------------------

--

To REPLY: If there are a couple of underscores in my return address,
you must remove them to reply directly . . . . . . Thanks.

Regarding stage performances: When everyone else has finished playing,
you should not play any notes you have left over. -

 

ESD (Electrostatic Discharge Machining) is supposed to be the answer
to that kind of problem. I've heard of plans for homebuilt versions
too, and always wanted to try buildiing one.

 

You'll find the front wheel drive an advantage. Get yourself a set of
Blizzaks for the winter, those 'all season' things are neither good
winter tires nor good rain tires.

Never mind the wheel wells. Pull up the carpets and check the
doorsills and floorboards. Keep salt laden slush from your boots from
making the carpets a corrosive poultice.

And here's a word of advice from a veteran of many Ontario winters...

www.por15.com

 

Nah, the idea with this car is to put as little money into it as possible...
Only what it needs to keep going. New tires when the ones on it have loads
of tread left is not practical on my budget. I just got this to drive until
I get my '68 running again and then to drive in the winters and/or long
commutes (to save gas). I think before lack of traction with the tires I got
now would be a problem I would be hitting the front bumper against the snow
which would negate any affect winter tires would have. Cheapo all-seasons
worked great on my '67 and '68 in the winter. I was even out driving in that
blizzard we had last year and had no trouble whatsoever on both plowed and
unplowed roads. I never liked the idea of FWD, but I suppose I'll find out
within a month or two how it is.

Will do. Cheap prevantative stuff like that is just waht the doctor ordered.

Yeah I've heard that's good stuff (expensive though). The undercoating on my
'68s frame is starting to peel off in some places and it has developed
surface rust on the frame in those spots. No big deal, but I plan on sanding
it down and coating it with POR15 since it will regularly see rain, and
perhaps occasional snow when I start driving it again. My '67 had a rotted
out frame and it wasn't pretty... I wanna protect my baby from the same
fate. The Honda though I consider almost disposable. I want to keep it going
as long as possible but I don't want to put a significant amount of money
into it (I don't mind prevantative maintenance and labor though). Between
the car, registering it, and an alignment I'm almost up to $500, which is
the most I wanted to spend on this.

 

Yeah I had tried with and without recirculation and it seemed to do a little
better with the outside air, though most of that affect was probably lost
due to the outside air being so much colder and no thermostat being in the
car. The other night the defroster worked better on the front window though
the side window defrsoters are woefully inadequate. They seemed to give me a
tiny little area I could barely see through. I think the vents may be
clogged or a vacuum motor not working properly as there is very little air
coming thorugh the door defroster vents on either side.