dgmorr

I've searched but only found a thread on overheating.

I have a 93 Si hatch with a B16A2.

I can drive for hours and the temp guage will be about 3 needle widths up from C. It does climb from when I first start, but no further than that. My heat also doesn't get very warm, it's warmer, but not warm and hot. The guy that did my engine said he used an aftermarket thermostat. So my questions are

1) Is it not heating up? Or is it just not reading properly?
2) Is the temp sensor on the rad or head side of the thermostat?
3) Could my heat be cool because of the thermostat not opening because it has a higher rating?
4) Will hot fluid boil in my head without me even realizing it?

swfitz2003

you could have air pockets in the radiator. start your car with the cap off and see if it bubbles at all and also while its running feel both of the main radiator hoses to make sure they are both heating up.

SkoundrelUSA

1) Make sure the car is completly cold
2) With the radiator cap OFF start the car and put the heat on defroster full blast
3) Bubbles will start coming out
4) Refill the radiator with coolant if the level goes down
5) Keep the car running till it stops bubbling and its full, and till the car reaches normal temp on the gauge

swfitz2003

dgmorr

Oh, I forgot to say, the coolant is fully bled. I did this last night with pretty much the same steps.

dgmorr

And even if it did have air bubbles (not ruling out that it doesn't, I will bleed again tonight), wouldn't the temp guage still rise....to maybe even on the hot side?

swfitz2003

air pockets can cause little to no heat, idle issues, and engine temp problems.

q45mm

Are you getting poor gas millage?

dgmorr

You're making me happy. I have a slight up/down idle (150 RPM fluctations). I hope this is the only thing. I hate changing fluids, I always spill things.

old man neri

Sounds maybe a bit like the wrong temperature thermostat if it is an "aftermarket one" or it is stuck open.

Quick way to find out. Cover half or most of your rad with cardboard and start driving around and see if it gets better. OR just let it idle for a long time and see if it heats up.

dgmorr

I did my first long distance drive on the B16A (200km) and got a little over half tank left. Compared to my D15B7, this is poor mileage.

What were you thinking?

dgmorr

Good idea with the cardboard. I'll try that if the re-bleeding doesn't work.

q45mm

When your t-stat is stuck open, your car runs rich in order to warm up ( and other things such as nox, co2, .... u get the point) So now more or less it that you have a big *** air bubble in the system or your t-stat is bad.

dgmorr

Thanks!

fms1day

May be your thermostat. It could be faulty and possibly left open. The thermostat is only supposed to open once the car/coolant is warm/hot so that cooler coolant can flow through, keeping the car at a constant warmth. If it's left open at start-up then it'll probably take quite a while for your car to warm up

TurboEM1

iTrader: (1)

your car is operating fine for the thermostat in it. It most likely has a lower (or higher, i always get it mixed up but i think its lower) temperature thermostat. It opens sooner to cool the engine then when it closes the coolant cools back down from the radiator. It never gives the engine a chance to get up to a higher operating temp and it never opens long enough to let the coolant get hot. This is leading to your lower reading on the temp guage (lower engine temp) and warm to cool heat (lower coolant temp). Swap out the thermostat for whatever temp rating honda uses stock or just get an oem one and all your problems will go away.

dgmorr

Is it better to have it running cooler? Or should your engine always be running at a given temperature. My guage is when warm is at 1/3 - 1/2 of where it normally is supposed to be.

fms1day

At warm, my gauge's needle is at about 40%.

dgmorr

Yeah, that's where it was always at in my last Civic. In this one it's about 10-15%. There is about a needle width between the C line and the needle edge.

old man neri

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dgmorr &raquo;</TD></TR><TR><TD CLASS="quote">Is it better to have it running cooler? Or should your engine always be running at a given temperature. </TD></TR></TABLE>

The engine should run at the temperature it is designed for.

dgmorr

I suppose cooler is not always better.

old man neri

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dgmorr &raquo;</TD></TR><TR><TD CLASS="quote">I suppose cooler is not always better.</TD></TR></TABLE>

Especially not if it leaves the car in the full rich cycle all the time like someone else mentioned. That will leave you with an empty gas tank and a clogged cat.

Rev2Eight

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by old man neri &raquo;</TD></TR><TR><TD CLASS="quote">Especially not if it leaves the car in the full rich cycle all the time like someone else mentioned. That will leave you with an empty gas tank and a clogged cat.</TD></TR></TABLE>

So what about getting a mugen thermostat? Will that hurt gas milage and the cat?

q45mm

^^^^

Depends on what point the thermostat opens. Also you're set up.
Probably wont hurt.

old man neri

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rev2Eight_EM1 &raquo;</TD></TR><TR><TD CLASS="quote">

So what about getting a mugen thermostat? Will that hurt gas milage and the cat?</TD></TR></TABLE>

Is there a specific reason you have for not getting a stock one?