Long struggle to fix overheating problem

[civic-dream]

Hi guys,

Here's a new update with my on-going struggle to fix my car's overheating problem...

Here's the order so far of what i've tried,

1. Radiator Flush and new coolant(several times)
2. Fixed wiring to fan coz it wasn't working at all.
3. Replaced Thermostat.
4. Cylinder Test for possible leaking headgasket <- no sign of leaking head gasket
5. Pressure test for leaks <-- showed slight leak from radiator hose and radiator cap.
6. Replaced leaking radiator hose, new clamps, replaced radiator cap.

I've left the mechanic everytime thinking the problem's been fixed but it just takes one day for the problem to re-surface !!! :confused:

I've noticed that the fan's not cutting in properly again...

In the past a mechanic friend of mine said that rust in the radiator can somehow stuff up the thermostat from working properly.. is this right?

so would my next logical step be to either recon or replace the radiator?

i'm so frustrated... *@#*&^@#%!!!!

any help??

[EG5[KRT]]

rust cant stuff up a thermostat

thermostat opens at certain temp.. unless the rust has contaminated the thermostat and the itself is rusting and stuck closed.. that might be a problem..

fans not cutting in properly maybe due to a faulty thermoswitch

when the coolant gets to a certain temp the fan operates..

usually when a car gets to operating temp the thermostat opens first.. then the fan operates.. otherwise the thermostat is closed on cold start.

check the actual fan motor and the wiring for it.. u can probably hook it up so that u can turn the fan on and off with a switch.. that mayb a ghetto style but it usually helps.

what else is wrong with the overheating ??

have u checked the water pump ??

[destrukshn]

re check the radiator.
even though you have flushed it with radiator flush.
check that it's flowing consistently.

[SINISTR]

i know its only a rough guess but have you had your cooling system BLED? there is a chance an air bubble could be getting trapped under the thermostat not allowing the thermostat to open causing the car to overheat?
yes there should be a bleeding screw somewhere near the thermostat housing.
Also have you opened up your heater and let some water circulate through that - another air trap right there.
the only other thing i can think of is you have a 'partially' blocked radiator - it looks fine, seems to flow fine but somewhere there is a blockage and you're radiator is possibly working only at 50/60% and thats why it seems to fault.

[e240]

fan switch?

[bigjo5]

check ur fan.. by directing current to it..like get a long wire and unplug the fan and put one bit of the wire on positve and hte second wire on the negative then use each end of it and put in in the plug"fan wires" and u should see if the fan works.

[MRH-22A]

just chuck out the thermostat... u dont realli need one.

my mum's eg had the same problems. threw out the thermostat and its all good.

[czy_sol87]

just chuck out the thermostat... u dont realli need one.

my mum's eg had the same problems. threw out the thermostat and its all good.

thats not even logical
without a thermostat, it will take forever to warm up the car to normal operating temp

are u trying to fix the problem urself or are u takin it to a mechanic? cause u said u took it back from the mechanics, but also say "i've tried" to fix the problem
if the mechanic isnt doin the right job then take it to someone else, it seams like his rippin u off, cause u keep comin back to him about the same problem
his paid to fix something, u shouldnt have to pay mulitple times for him to "fix" a problem

if u've tried all the above then, it could be ur water pump, is it leakin anywhere?

[egSi]

i had a similar problem, changed everything, raidator, pump and then found out it was the head gasket, reubilt the motor blah blah.

any coolant lines blocked? i had a kinked bypass hose which wasnt the source but it didnt help.

is your water pump leaking?

[TKO]

i had a similar problem, changed everything, raidator, pump and then found out it was the head gasket, reubilt the motor blah blah.

any coolant lines blocked? i had a kinked bypass hose which wasnt the source but it didnt help.

is your water pump leaking?

How's the head gasket affect the water temperature?

I also have over heating issue with my EG5 and i could like to know more about this topic. Since this is the first time i read about head gasket causing over heating. Could you please explain it to me.

Also i could like to know which point in the water circulation does the temp gauge in the dash broad measure? Is it at the thermostate or inside the engine housing or at the radiator or somewhere else?

How is water circulate inside radiator? It is all from top to bottom in one single pass or goes like a 'S' from top to bottom in multi passes?

Sorry to ask so many noob questions here. Happy to delete when directed.

[czy_sol87]

here is a site to look at, or u could search further on here or honda-tech
http://auto.howstuffworks.com/cooling-system.htm

well the headgasket doesnt directly affect the water temp, it would most likely be that, u've either, let the car overheat too much into the "red" zone for too long, or it has overheated too many times and over time has "warped" the head, causing water to not "flow" the right way

[egSi]

lol

engine oil + coolant mixing = bad ;)

[civic-dream]

here is a site to look at, or u could search further on here or honda-tech
http://auto.howstuffworks.com/cooling-system.htm

well the headgasket doesnt directly affect the water temp, it would most likely be that, u've either, let the car overheat too much into the "red" zone for too long, or it has overheated too many times and over time has "warped" the head, causing water to not "flow" the right way

My mechanic did some sort of test for the headgasket, i can' remember exactly what it was called but it involved some sort of chemical being put into the cylinders? anyways he concluded that it wasn't the headgasket..

is that a fair way to test the headgasket if its been warped?

[civic-dream]

i know its only a rough guess but have you had your cooling system BLED? there is a chance an air bubble could be getting trapped under the thermostat not allowing the thermostat to open causing the car to overheat?
yes there should be a bleeding screw somewhere near the thermostat housing.
Also have you opened up your heater and let some water circulate through that - another air trap right there.
the only other thing i can think of is you have a 'partially' blocked radiator - it looks fine, seems to flow fine but somewhere there is a blockage and you're radiator is possibly working only at 50/60% and thats why it seems to fault.

Hey thanks for the input... i'm suspecting it might be a blocked radiator too.. and like i was just advised i think i'll get my mechanic to do a flow test to check it out..

my previous radiator hose was bulgy from excess pressure.. is this an indication of a blockage somewhere?

one more thing... the coolant level keeps dropping so i'm guessing the theirs still a leak somewhere..

[kraiye]

fan relay maybe ?

[MRH-22A]

thats not even logical
without a thermostat, it will take forever to warm up the car to normal operating temp



how dare u tell me its not logical and give me a bad rep for wrong advice!

like i said. the same thing happened to my mums car.

i took it to my friend's workshop... he is a mechanic. he explained that the car doesnt need the thermostat unless ur livin in really cold conditions and its always snowing.

my mum's car never has a problem reaching normal operating temp. im not posting from theory. its seen and done! and it works!

[Drew]

How's the head gasket affect the water temperature?

Rather easily
Oil contaminating the water and lowering the boiling point, and water leaking into the cylinders...

Check your oil see if its like a brown/chocolate milky kind of color

It could really be anything...

Radiator not turning on is probably just one of the problems...
Rusty/blocked/dirty radiator is probably another
If the radiator is rusty or full of crap/sludge then it could be blocking the water ways in the engine or just not passing water quickly enough

Check your engine for a blown head gasket; then get your radiator reconditioned and hard wire you fan or get a new one.

Failing that; get the water ways in the engine pressure cleaned or something

Also what thermostat are you using? Get am OEM one
I bought a so called 'high flow' thermostat from Repco, the thing flowed about half of what the OEM Honda thermostat flows thus caused overheating issues; couldn't drive my car over 80km/h or it would overheat and couldn't give it any...

Simply removing the thermostat isn't doing you engine any favors either... Without it the engine takes a lot longer to heat up thus clearances aren't right within the engine and probably causing it long term damage


he explained that the car doesn't need the thermostat unless ur livin in really cold conditions and its always snowing.

I call bullshit!

[green_machine]

there r 2 sensors for the cooling system...1 on the thermostat housing and 1 on the block..check resistance on both at operating temperature..
get a wire and put both ends in to the sensor plugs ,thermostat housing plug should activate the fans and the 1 on the block should activate the temp gauge.

[MRH-22A]

I call bullshit!

I'm blardy serious! I've done it to my mums car! Me and my mechanic friend took out the thermostat! and the car runs perfectly!

Go ask a mechanic before u call bullshit

[Drew]

oh no you didn't

I half own a Auto Workshop in Reservoir (as of next month anyway:)), my step father is a Diesel and Marine Mechanic and my father is an Aeronautical Engineer...

Although the car may 'run' just fine; doesn't mean that it's good for the engine... and I particularly call bullshit that you only need a thermostat in Siberia...

My old prelude without a thermostat took the better half of an hour to warm up instead of the normal 2-5 minutes on an autumn morning...
Not freezing cold; not snowing; ambient temperature of maybe 15deg at the least...

There aren't any immediate adverse affect on the engine but there are long term repercussions

It's there for a reason... Mr Honda knows a little bit more about engine's than your average Joe mechanic

The thermostat also maintains temperature rather than just a straight open/close
If you are driving late at night on a cold evening at say 100km/h just cruising along... The thermostat will close up a little tinny bit to reduce the flow of water thus increasing the temperature to keep it within operating temperature...

[MRH-22A]

Look mate. My mum's car warms up fine without the thermostat so that's what im gona post. I had a work friend who told me the same thing about his car! And you make it sound like im lying.... calling bulshit. why cant u accept that it may work for some ppl and it may not for others?

[JasonGilholme]

check to see if your thermostat is working 100%, also while your at it you might want to flush the block and bleed it. There may be something stuck in one of the water gallaries somewhere.

[Drew]

Look mate. My mum's car warms up fine without the thermostat so that's what im gona post. I had a work friend who told me the same thing about his car! And you make it sound like im lying.... calling bulshit. why cant u accept that it may work for some ppl and it may not for others?

I'm not saying or implying that you are lying... I'm simply saying that what your mechanic said about only needing a thermostat if you live where its mega cold and always snowing is bullshit...

It may very well work for a lot of people; thats fine.
If it works for you than thats cool

:wave:

Seriously no hard feelings :)

[JasonGilholme]

If you've got a thermostat leave it in. It lets the car warm up quicker which ensures that you don't get any premature damage to the internals of the engine.

If you've got a fcuked up thermostat replace it for the reason mentioned above.

Thermostat > no thermostat