System which removes excess heat from liquid cooled internal combustion engine. It also helps maintain the engine temperature at a consistent level. The cooling system encompasses the radiator, water pump, thermostat, hoses, heater core, overflow reservoir, and anti-freeze (or coolant).

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43 views

2006 VW Jetta Diesel won't warm up

A couple of years ago the VW (2006 Jetta) quit warming up. No heat, no defrost, temperature gauge reads cold! I changed thermostat and tested both 'stats at the same time. Both opened right at 195 ...
9
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1answer
72 views

Coolant Reservoir

Two questions, One, is there any reason why some coolant bottles are shaped in this way? Two, if this coolant bottle was placed on its side such as in the image below for example would coolant ...
5
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1answer
74 views

What exactly is meant by “engine coolant”?

I know that engine coolant is a fluid in the engine used to dissipate heat spots and keep the engine cool in general as the moving parts generate heat. In this context, I would call the oil an "engine ...
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1answer
25 views

2000 Vw passat 1.8l oil is in radiator

I have a 2000 VW Passat GLS 1.8l and it has oil in the radiator reservoir. and my Oil light says oil compression low. i flushed the radiator and found oil in it again, (the radiator overflow) it ...
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1answer
17 views

1978 Ford 302 is using a lot of water

My 1978 Ford 302 is using a lot of water. There is no oil in the water or no water in the oil and I cant find any leaks. What can I do?
4
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1answer
112 views

How can I test my thermostat?

How can I tell whether a mechanical thermostat works as it should? Is there a test that can definitively tell me if a thermostat is good or bad?
4
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2answers
49 views

Replace Yamaha FZ6 radiator for two smaller ones

I bought the engine of a Yamaha FZ6. I want to use it to run a competition single seater car we are builiding in the university. The engine didn't bring the radiator with it. I would like to ...
8
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3answers
236 views

Car won't reach operating temperature

Here's a seemingly simple problem - I noticed that the temperature gauge of my mother's 2004 Opel Meriva 1.7CDTI won't ever climb above minimum. I checked the OBD readings to see if it was a defective ...
5
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2answers
42 views

Water underneath floor carpet - Mazda Protégé 2002

I just bought a Mazda Protégé 2002 and a few weeks later I noticed a damp spot on the back passenger side floor. Very wet and soaked. Later I noticed the smell grew larger and the vapor on the glass ...
5
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2answers
70 views

Why is antifreeze mixture not as stated?

To keep things short I poured 200ml of concentrated genuine ford super plus premium antifreeze (Ethylene glycol based) within a bowl. Then added 200ml of water to dilute the solution to a 50/50 ...
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2answers
67 views

Coolant disappears from coolant reservoir but no leak observed

I just replaced the water pump in my 2005 Ford Escape V6. I discovered that each time I fill the coolant reservoir with coolant and drive the car, by my next stop the coolant reservoir will be ...
2
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0answers
94 views

E46 rough idle with coolant light on

The car is 2001 BMW 330i. I have changed ignition coil, spark and IAC. Last week, my car experienced rough idle. Then I changed the coolant temp sensor today. After adding coolant and bleeding, the ...
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votes
3answers
452 views

Blocked water flow in engine?

My dad has a 1993 Subaru Legacy L 2.2L (no turbo) with a perplexing cooling problem. It overheats, and there doesn't appear to be flow through the cooling system. The upper radiator hose is extremely ...
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1answer
44 views

Engine oil going into the coolant

My 2005 Saturn Relay got a hole in a water hose and suddenly overheated, so I shut it down immediately. Found the crank case empty and the coolant full of oil. Replaced the hose and put oil in it, ...
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1answer
78 views

Does using heat in the car SAVE gas?

Its well known that using heat in a car is almost free (see for example here). It is also known that using the heat can reduce the engine temperature which otherwise needs to rely on water cooling. ...
5
votes
1answer
517 views

Should overflow tank be filled when replacing coolant?

I have recently fully rebuilt my engine, minus the block and pistons. All the gaskets were replaced, valves lapped, valve lashes tuned etc. I did it because I had an overheating problem and a head ...
3
votes
0answers
111 views

2002 Dodge Ram 1500 overheating

I have a 2002 Dodge Ram 1500 two wheel drive with a 4.7 liter engine. It's been overheating so I replaced the whole cooling system: I replaced the condenser cooling fan because its not coming on ...
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votes
2answers
148 views

Mazda 626 with Unknown Coolant Leak

I'm looking at a 98 Mazda 626 2 liter with an unknown coolant leak from the area in the back of the engine. Seller says a mechanic that quickly looked it over said he thinks it's either the head or ...
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votes
0answers
49 views

Changing Freeze Plugs on a Mazda 626

On a 98 Mazda 626 4 cylinder 2L engine where are the freeze plugs and how hard is it to replace them?
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votes
2answers
83 views

Is it necessary to maintain antifreeze to water ratio?

I had my radiator cleaned and flushed yesterday. The mechanic who did the work advised that pure distilled water is better than using mixture of water and coolant. I checked the manual and it just ...
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3answers
322 views

Do cowl hoods actually help with engine cooling?

I've read that cowl hoods used to be the method for air induction for older vehicles with carburetors and that the only purpose they serve for vehicles with fuel injection is for looks. However, I ...
3
votes
2answers
100 views

1.6 Petrol engine overheats intermittently

I have a Vauxhall Vectra 1.6 (2007). The cooling system operated perfectly (a few kms after starting the engine the needle was pointing to optimum temperature without the slightest waver). 2 weeks ago ...
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1answer
30 views

How to test if heater core is causing cooling malfunction?

My 2007 V6 Tacoma is overheating, I have done just about any test imaginable, replaced the thermostat, water pump, did many other checks, incl. chemical test for gas residue in the coolant system etc. ...
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votes
3answers
1k views

How to test if head gaskets are blown?

Is there a definitive way to test whether head gaskets in most engines are blown, without actually reaching for the gaskets themselves (at which point you might as well go ahead and replace them) ...
3
votes
1answer
2k views

Flushing built up Rust and Mineral Deposits in Cooling System

The previous owner ran tap water in the cooling system for few years, and we have very heavy, mineral rich water locally. When I bought the car about six months ago, I drained the water, and put a ...
3
votes
1answer
5k views

Coolant spillover tank boiling but engine not overheating

After driving some time, is it normal that the plastic spillover coolant tank, usually attached to the fan housing, that takes boiling overflow, get so hot that you get bubbles boiling out of it even ...
4
votes
1answer
183 views

Flushing coolant after driving only with water in

If I drive my truck for 30 min with just water in my system, would it be equivalent to just flushing it stationary (the proper way to flush it)? IOW, if I just drive around with a clean water refill ...
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3answers
3k views

Pros and cons of using straight antifreeze

I've heard from some people that they use straight antifreeze in their cooling systems and not 50/50. What are the pros and cons of doing that? E.g. does it reduce exposure to corrosion?
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votes
1answer
4k views

Can a blown head gasket cause overheating, without losing coolant?

My 2006 Subaru Outback overheated when my wife was driving. I got to the car that evening and its radiator was pretty low. I refilled it, and the car ran fine for a week. Then it overheated again. ...
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votes
2answers
290 views

Ditch water in radiator

I lost a coolant hose going down the road and all my antifreeze was gone. I found a puddle along the road and filled my radiator back up after I fixed the hose. Will this cause electrolysis in my ...
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0answers
42 views

Best way to control engine cooling? [closed]

Should I control engine temp with a thermostat or with a cooling fan temp sensor for on/off of cooling fan? I am installing a Tri cross flow alum radiator with full alum shroud and a special 16 inch ...
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vote
2answers
102 views

2005 Honda Civic - Oveheating [closed]

So my car has been overheating for over 1 year. It overheated during summer or when I went 80mph only. I recently saved up enough money to get the car fixed. I brought it to my mechanic and informed ...
3
votes
1answer
991 views

Should I remove the thermostat when doing a cooling system flush?

I am going to do a cooling system flush and after some reading and watching some youtube videos I noticed that people take different approaches. So I have the following questions: I understand that ...
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vote
3answers
13k views

car over heating and white smoke coming out of the hood

I have a 98 Honda civic that I bought a few months ago. It has an after market fan that i have to turn on when I'm driving to keep it from over heating. In the winter time it wansnt a big deal to turn ...
4
votes
2answers
410 views

Bad Dashboard Coolant Temp Sensor?

In addition to the coolant temp sensor hooked up to the ECU, I have a second, single wire coolant temp sensor which is hooked up to the dashboard display. When the coolant temp is around 85C, right ...
4
votes
1answer
6k views

Engine's Normal Operating Temperature

I read in the Motor Oil University article on Bob the Oil Guy's websites that: The automotive designers usually call for their engines to run at 212°F ( 100°C ) oil and water temperature with an ...
8
votes
2answers
59 views

Ford Expedition Eddie Bauer 4.6 V8 2003 automatic rpm goes high

When driving, sometimes when I want stop the vehicle, I go to press the brakes, but that time engine rpm goes high, keeping brakes pressed hard, after 5 second engine becomes normal. It goes high when ...
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1answer
126 views

After car runs with temp normal it drops to tempature reading cold

My car temp reads normal but after warming up the tempature drops showing on the gauge engine is cold and the heat in the car gets cool
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1answer
398 views

Dodge Ram 1500 SLT 4.7 Losing Coolant

I have a 2003 Dodge Ram 1500 with a 4.7 magnum, and I have replaced the radiator, thermostat and water pump. I keep having to fill the reservoir every couple of days. Fluid keeps coming out of the ...
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votes
1answer
48 views

When pouring in anti-freeze why does choking the hose allow it flow better

Just wondering what exactly is going on there. When I pour in antifreeze and choke the the hose the antifreeze flows a lot better through. Any idea why this is? Thanks
3
votes
2answers
159 views

MK 1 citi sport temp gauge fault

I own a MK 1 Citi Golf Sport 1.6 Carb that has 523220 km. I recently flushed the cooling system and changed the coolant. After the flush the temperature showed above normal despite changing ...
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vote
1answer
63 views

Oil in the cooling system

I have a 2003 Chrysler GT, PT Cruiser with less then 60000 miles. It is a four cylinder 2.4L, that is turbo charged, and is automatic. I had a hole in the over flow tank and had it replaced with a new ...
2
votes
1answer
277 views

Changed thermostat but now constant leak around thermostat housing

I went to flush my cooling system and change the thermostat on my Mk1 Golf. All went fine until I put the new coolant in. There is a pretty steady leak from the thermostat housing. I've tightened ...
0
votes
1answer
157 views

Motor Oil in Coolant Reserve [duplicate]

2004 Mercedes E500 - Yes, I am sure of it. In a moment of stupidity, I added about 8oz of motor oil to the coolant reserve. I have heard nothing will happen and I've also heard it can mess up the ...
4
votes
1answer
631 views

2015 STI White smoke

My 2015 Subaru WRX Sti is emitting white smoke from the exhaust. The smoke smells like burning electronics. When I pull over and open up the hood, I also see white smoke in the engine bay. The smoke ...
3
votes
7answers
44k views

The mysterious overheating honda civic

This is a tale that goes back about a year when I found my very first car. I needed it to commute back and forth to school. When I bought the car it worked great, everything I could have wanted. ...
4
votes
1answer
135 views

Car is heating while Coolant Temp Sensor is normal

I bought a BMW 318i and the car heated twice so far while the coolant temperature sensor is normal. If we exclude the possibility that the sensor is malfunctioning, what problem would cause the ...
2
votes
1answer
392 views

Engine temperature increases when idling though thermo fan is working

I am trying to diagnose an issue with my Mk1 Golf. The engine heats up when the car is idling or in traffic but cools down almost instantly when I start moving again. I would presume this is the ...
2
votes
4answers
791 views

engine has too much cooling especially when driving hard

I'm trying to figure out why my engine temp is always very low. I do know for a fact that my gauges work. My car is a 4-afe toyota with a stock radiator and a modified fan. I also installed 2 ...
2
votes
2answers
126 views

1996 mazda 626 leaking coolant

My mazda 626 was leaking coolant. I replaced the radiator for there is clearly a hole on it. It worked fine for about a month. Then I see some leakage again. And this time it is around the right side ...