Hi everyone,

About a week ago I noticed that when I was sitting in traffic the temperature gauge would rise up then as soon as I moved away it would drop down again. Over the past couple of days its started going up all the time. The temperature drops a little when I put the heater on full (a tip I was given). A guy I know at a garage said to put k-seal in the radiator which I've done but doesn't seem to help. A couple of people have mentioned the thermostat may be faulty or could be head gasket. Was hoping someone might have some suggestions.
There are no warning lights coming on. One other thing is occasionally when I start it up the revs drop and cuts back out.

It's a 1998 impreza sport 2.0 non turbo with no modifications.

Thanks in advance for any help.

 

Carry out the following checks and report back:

1. coolant level, is level low ?
2. does radiator fan kick in when engine is hot ?
3. Check oil quality, does it contain any white substances ?

 

First thing I would do is not drive it . Change the thermostat and a coolant change and make sure there is no air locks in the system as this can cause over heating.
Make sure the fan is coming as said already and go from there , If the problem isnt solved its a head gasket more than likely

 

I originally thought it might be the fan but that's working fine. Coolant level is a little high since the k seal was put in. Checked oil this morning and looks like it should. However I went to start it this morning and its like the battery is dead. It's just clicking.

 

Probably is with the weather. Whats a K seal mate?

 

It's a nasty chemical added to the coolant system to bodge leaks.

As mentioned, check coolant levels first. Why did they tell you to add k seal in the first place? Is your rad knackered?

 

Yep cold weather kills weak batteries and K seal is just a bodge fix.
If the coolant is not contaminated and the level is stable, you now need to check the radiator for hot spots, thermostat operation and water pump condition.
If the radiator seems fine, and the water pump is not leaking or making a noise, I suggest you change the thermostat as its fairly easy to change.
If the thermostat does not cure the problem you need to carry out a block test (suspect head gasket !!).

 

Hi everyone,

Sorry ive not replied to any messages for a couple of days.

The situation now is....

The day the car wouldnt start my uncle came down and started it with jump leads. He said its probably a coincidence that the battery died. When he checked the car over we noticed that although the coolant expansion chamber was full the radiator didnt have much water in it. Once we filled that I went for a short drive and the temperature gauge was going between half and 3/4. For the next couple of days it was kind of ok (temperature level fairly normal). Put it in to my local garage for a service and new battery. Got new air filter, fuel filter, oil filter, oil change, spark plugs, coolant etc. When I checked it over I noticed he had filled the expansion tank right the way up over the full line. Now after a bit of time the temperature gauge goes near to the top so I put the heater on full and it comes back down. When I was leaving for work tonight the car didnt start first time (I thought the new battery would have resolved that). Needed to give it a couple of revs when starting.

For people wondering about k-seal...It apparently seals up parts of the system (head gasket, cylinder heads etc). Ive heard plenty good things about it. It says its a permanent solution but if that was the case no one would ever need a new head gasket.....I think it just puts off the inevitable. The reason I was told to put in the k-seal was the guy at a garage I went to said straight away it was head gasket and to put it in.

Ive noticed a couple of people mentioning the thermostat. Does anyone know how to replace it..is it easy enough to do myself or would I need a mechanic to do it. Thanks for all the replies.

 

...Also meant to say that the oil seems fine, theres nothing bad coming out the exhaust, no noises from water pump but my uncle did notice that the bottom part of the radiator was staying quite cold. I asked the guy at the garage to empty the radiator etc to see if there was maybe an air lock or something when he was doing the service.

 

I had this problem with my wrx dunno if it's the same problem but thought I'd post anyway when I was sat in traffic the temp would fly up quite worryingly high but soon as I moved off it would drop back down turned out it was a air lock in the coolant system what I did was i burped the system take the cap off the expansion tank (the metal one) when stone cold turn your heaters on to hot and full turn the car on and let it idle and keep it topped up for about ten mins any air locks in the system should burp out hope this helps

Craig

 

Airlock or failing thermostat......

 

You need to have the cap off the header tank as well as this is the highest point of the system. Expansion tank is on the far right beside the battery topping up there is not going to cure an airlock

 

That's what I meant lol the metal one on the left of the engine

 

Ok I was just pointing out its not the expansion tank , the expansion is in the inner wing on the passenger side

 

From what you just said it could still be the head gasket as diagnosed by the previous mechanic. Did he tell you how he came to that conclusion?
A quick test would be to from cold, start the car with the expansion cap off and watch to see if the coolant level rapidly rises and overflows (or starts bubbling). This will give an indication of combustion gas in the cooling system. This test is not 100% accurate and only really shows up obvious head gasket failures. To be more accurate a block test needs to be carried out.

If its not the head gasket, suspect air lock or thermostat as already mentioned by baz and craig

The thermostat on a turbo impreza is quite easy to change, but you will need to drain the coolant system again. Looking at the front of the engine the thermostat is located at the bottem right corner where the bottem radiator hose attaches. You need to :

1. Drain coolant into suitable clean container
2. Remove bottem radiator hose.
3. Remove the two bolts holding the thermostat housing.
4. Remove housing and then thermostat.
5. When replacing the thermostat make sure the bleed hole is on top.

Hope this helps.

 

Thanks for all the replies. Im going to get the thermostat done and take things from there. Ill maybe try "burping" the system first. Things seem to have reversed slightly as before the car would heat up when stationary but now it only heats up when sitting about 60-70mph. Also the radiator seems to always empty into the expansion tank. I take coolant out the expansion to get it to the proper level and put it in the radiator but after a run it seems to go straight back into the expansion tank. Also at times theres a strong smell of burning coolant.

 

You sure its no a faulty header tank cap?

 

radiator is over pressurising and pushing the coolant out of the rad via the overflow bottle,happened on mine last year,was the head gasket.

 

im having very similar issuses but im having to run the car without a stat until this friday as i cannot get one until then and i need the car for work.. even though mine has no stat now im still loosing water somewhere? its been pressure tested and its not the head gasket so im stumped lol

 

K Seal is horrid stuff and I would personally flush the coolant system out to try and remove most of it. I would rather find the actual fault than put this stuff through it.