Thermostat. Anyone Against Taking It Out Completly?

Started by misterrick · Oct 25, 2007 · 18postsInvision 2005–09

misterrickOct 25, 2007, 12:05 am · #1

ok so i flushed my rad recently and its started to overheat while at idle or low speeds, and from what ive read its probably just vapor-lock due my my lack of bleeding it. anyway point being, ive always heard that you can just take out the thermostat and have extra cooling. what are the side effects? im sure it wouldnt put out as much heat, which i need being in cananda at this time of year lol.

is there anything else i can expect besides better performance?

KeithOct 25, 2007, 5:23 am · #2

misterrick @ Oct 25 2007, 12:05 AM

is there anything else i can expect besides better performance?

More than likely it'll run super rich, because the ecu will always think it's in warm-up mode. It will do more harm than good over time.
If you have issues at idle, and low speeds, thats an indication that your fan can't keep up to the demands. If you think air is trapped...just take off the rad cap, and squeeze the top hose several times until all the air bubbles fart out. Did you put the jiggle valve at the top?

OzchuckOct 25, 2007, 1:57 pm · #3

^^ the thermostat is not connected to the ECU, so there will be no running rich. the temp sensor is connected to ECU though.
If you live in an area where is gets below 0ºC and you need to drive, I would leave the thermostat in.
Its not really an obstruction unless it stops working, so wait for that ok?

CallaroSXOct 25, 2007, 2:16 pm · #4

Im sure you could find a Low temp thermostat and a better radiator, coupled with electric fans if your looking for better cooling.

KeithOct 25, 2007, 2:54 pm · #5

Ozchuck @ Oct 25 2007, 01:57 PM
the temp sensor is connected to ECU though.

Exactly........if the coolant temp sensor is always reading cold, it will tell the ecu, and it will always be in warm-up mode, which during warm-up mode is a rich condition.......and will gunk up everything over time.
I use to use a 160 t-stat on my ca18et, for a few years. Same thing.......always ran in warm-up mode, and my plugs always fouled up......even after a few hundred miles.
Do a google search......there is plenty of info out there on this.

Best thing to do would be to check the condition of your radiator, radiator cap, t-stat, water pump, fan.....once you determine everything is ok.....drain radiator/ block, get a 180 t-stat, some Redline Water Wetter, and refill the system with 30% antifreeze, 70% distilled water, and a bottle of Water Wetter. The system cools better with less antifreeze......30% will keep it from freezing, water wetter helps reduce head temps further, and has inhibitors in it to keep the system clean

misterrickOct 25, 2007, 11:39 pm · #6

i dont have a jiggle valve anymore i dont think. im running a standalone so it doesnt have the normal "warm-up mode".plus the cold start menu hasnt been set up yet. water pump is brand new. fan is a brand new perma-cool.the thermostat i changed a couple days ago. i flushed out the rad a couple times so i dont think theres an obstruction but i plan on changing the rad anyway in due time. im gonna try just squeezing the hose with the cap off tonight. hopefully that will tell the tale.

rageOct 25, 2007, 11:50 pm · #7

i wouldnt take it out completely. for race-only apps, i would take out the valve and just basically have a restrictor. if you take it out completely, the water will be moving too fast to properly cool.

misterrickOct 26, 2007, 12:13 am · #8

damn thats a good idea. i even have an extra thermo.

IggyEGuanaOct 26, 2007, 1:40 am · #9

rage @ Oct 25 2007, 04:50 PM
i wouldnt take it out completely. for race-only apps, i would take out the valve and just basically have a restrictor. if you take it out completely, the water will be moving too fast to properly cool.

Word. The theory here is the coolant doesn't spend enough time in the radiator to transfer all the heat its gained. It superheats and then you're screwed. In practice it seems that the characteristics of any given cooling system depend widely on its design and the engine its cooling. Older cars for the most part seem to be the ones that can get away with running no t-stat. I would guess its because they don't have picky computer control systems that freak out when things change from factory spec.

Check your oil. Headgasket might be a suspect here.

misterrickOct 26, 2007, 1:45 am · #10

i just changed my oil a few days ago and it was fine then. im kind of hoping its not the headgasket sad.gif i guess if the level drops it would be a good place to start though....gotta keep my eye on it

KeithOct 26, 2007, 5:04 am · #11

misterrick @ Oct 25 2007, 11:39 PM
i dont have a jiggle valve anymore i dont think.

The jiggle valve is built into the t-stat itself. The t-stat should be situated in position so the jiggle valve is in the 12 oclock position......it acts like a air bleeder to help expel air out of the system. See below..............

IPB Image

misterrickOct 26, 2007, 5:21 am · #12

ooohhhhh, now i understand. yes i did install it up actually. i went by how the old one was. it was also the same deal on my integra the thinger had to be up lol

KeithOct 26, 2007, 5:25 am · #13

Dumb question.....but did you install the t-stat in the right direction? That would cause heating issues if it is installed backwards......just a thought

misterrickOct 26, 2007, 5:37 am · #14

hmm....i didnt think it could even fit backwords. the front of it is the like v-shaped part right? im trying to picture it when i put it in. may be a dumb question but ive been known to do dumb shit....

Keith @ Oct 25 2007, 11:04 PM
The jiggle valve is built into the t-stat itself. The t-stat should be situated in position so the jiggle valve is in the 12 oclock position......it acts like a air bleeder to help expel air out of the system. See below..............

so in the pic, thats how you should see it in the housing right?

KeithOct 26, 2007, 6:09 am · #15

misterrick @ Oct 26 2007, 05:37 AM

so in the pic, thats how you should see it in the housing right?

Yeah.........that part should be facing the radiator......the spring side faces the motor

OzchuckOct 26, 2007, 6:12 pm · #16

Keith @ Oct 25 2007, 02:54 PM
Exactly........if the coolant temp sensor is always reading cold, it will tell the ecu, and it will always be in warm-up mode, which during warm-up mode is a rich condition.......and will gunk up everything over time.
I use to use a 160 t-stat on my ca18et, for a few years. Same thing.......always ran in warm-up mode, and my plugs always fouled up......even after a few hundred miles.
Do a google search......there is plenty of info out there on this.

For the temp sensor to always be reading cold, obviously the thermostat would have been needed in your particular environment. no thermostat = always too cold water in the engine.
Taking it out was obviously a bad decision in your case, where the air must be heaps colder, or you drive VERY gently.
where I am its almost never below 25ºC, so the engine needs about 20 seconds to heat up.
As I said, if you're in the cold you'll want to keep the thermostat, as that is exactly what its there for.

As for the restrictor idea, the suction to the water pump is the bottom of the radiator.
This suction has all the head from the water in the top of the radiator feeding it.
Theres also about 10PSI of pressure in the hot section of the radiator.
Also theres a lot of restriction already in the block itself,
all these things add up to the fact that yanking the thermostat isn't going to have a negative effect on the flow rate of the water.
Not to mention the pumps speed is fixed to the engine RPM, which fluctuates a fair bit.

You're right in saying tat more modern engines tend to have issues when you yank the thermostat, with the thermal balance and the efficiency of the engine and water galleries blah blah blah.
But the CA18 is hardly a modern engine tongue.gif

Try the car without the thermostat for a while and see if this fixes your problem.
After that, jack the front of the car up a stack so the radiator is heaps higher than everything else, and crank the car over with the cap open.
There should be stacks of bubbles and the radiator level should go down, so keep topping it up until it stops.
Then squeeze the bottom hose and check for bubbles etc again.
Also check that the bottom hose still has that spring in it keeping it open, sometimes that fails and the water pump sucks the hose shut.

misterrickOct 26, 2007, 6:18 pm · #17

i didnt even know there was a spring in the lower hose. i didnt put the hoses on originally though......

200sxkitcarNov 13, 2007, 3:36 am · #18

Just because it is a new t-stat, doesn't mean its a good one. I replaced one in a Pontiac Sunfire once, only to have it shit out within a couple of months. I went with a better quality one (NAPA) since the dealer unit was no longer available and no problems then. There are all different levels of quality of aftermarket components, even if you got a good one doesn't mean it wasnt a dud lol. Except for Fords which will belch up whatever thermostat brand you put in them. My buddy replaced his on average at least once a year in his Explorer.