Technical Overheating

[mark2004uk]

My car for some reason has started to overheat, I did notice water running from the rad area at the front, i topped up the rad but water did not run out.... I put some radweld stuff in and two bottles of coolent, it still over heated, but no signs of dripping. I looked under the oil cap and dipstick all clear. I don;t know where the bleeding things are to bleed the cooling system.. i think the fan does kick in.. i also think that the air is blowing cold into the car.... Id like to see the themostat but i have no clue where it is or how to get it out. My injector light has been coming on and off for a bit now, could this be linked? could i just need to change my filter?
i go about 4 miles and the engine temp goes full...

 

[mark2004uk]

After leaving the car to cool down i went back and topped it up with water and sat with the car on for 30min, the fans in the car came warm and the water did not go... also the temp did not go above half way... so fingers crossed... a lad passing who works at a garage said i have a bit of white smoke coming out and his hand got wet near it, he said the HG may be on its way... I dunno

 

[m20b25]

Id start with looking at the thermostat then the waterpump.

Injector light coming on could be related, engine getting too hot and knocking.

 

[nunesaf]

After leaving the car to cool down i went back and topped it up with water and sat with the car on for 30min, the fans in the car came warm and the water did not go... also the temp did not go above half way... so fingers crossed... a lad passing who works at a garage said i have a bit of white smoke coming out and his hand got wet near it, he said the HG may be on its way... I dunno

Radweld is not a brilliant idea to be honest, as you run the risk of blocking the system elsewhere and it is a pain to clean.

If you have cold air in the cabin, it is due to an air lock - or simply the system could be blocked there and the radweld just made it worse.

The air lock could be due to a leak somewhere or could be engine blowing air into the cooling system due to the HG failure.

Before you put out car in the hands of a mechanic to change the HG, try to identify the source of the leak. It may not be evident but some patience and method will pay off. Leave a clean paper sheet underneath the car after turning it off and see if water drips somewhere.

BTW - which engine you got?

 

[mark2004uk]

Radweld is not a brilliant idea to be honest, as you run the risk of blocking the system elsewhere and it is a pain to clean.

If you have cold air in the cabin, it is due to an air lock - or simply the system could be blocked there and the radweld just made it worse.

The air lock could be due to a leak somewhere or could be engine blowing air into the cooling system due to the HG failure.

Before you put out car in the hands of a mechanic to change the HG, try to identify the source of the leak. It may not be evident but some patience and method will pay off. Leave a clean paper sheet underneath the car after turning it off and see if water drips somewhere.

BTW - which engine you got?

I have the 1.8... one day its fine the next overheats just after going 5 miles.... im crap at cars but I want to do more... how and where do i bleed the airlock? (any pix of bleed points) where the hell is the thermostat (pic) can this be cleaned ? I don't even know where the HG is.... or what I can do with it... my rad seems to have stopped dripping now too..

 

[mark2004uk]

very intermittent is this problem, it's on and off in just one journey, the heat in the car is on and off and the temp goes from half to near top back to half in just like a 7 mile journey.

:bang::bang::bang::bang::bang::bang::bang::bang::bang::bang::bang::bang::bang::bang:

 

[bigbrava]

mate you really shouldnt of put the radweld in it will stop any small leaks but for sure it will clogg up the water ports in the engine and small pipes ect...heres what i would do as ive done it before and got away with it.

1) disconnect both the hoses from your heater the ones going into the bulkhead behind the engine and attach a hose pipe to one of them and flush the water out.
2) also repeat it again by flushing the radiator hose (top one) and allow the water to run out of the heater outlets on the bulkhead.
3) when you have clear running water coming out refit all the hoses.
4) top up the expansion bottle with clear water.
5) no heres the funny one but it works (put in one dishwasher tablet in the expansion bottle and start up the car, allow it to dissolve or what i did was crush the tablet into powder and poured that in (dont rev the engine though)
6) disconnect the hoses again after you have run the engine for about half an hour and flush all the water through again as per the instructions above.
7) re-put fresh water in and the correct amount of anti freeze and run it again for half an hour and see what happens but dont forget to bleed the system to get rid of any airlocks....good luck m8

 

[bluejohn125]

Varying water temperature readings and intermittent heater performance are indications of low coolant level, possibly due to airlocks (or continuing loss).

As has been said above, get to know your cooling system and do some basic maintenance on it, then you or a helpful garage should be able to diagnose the real problems. Worst case will be a cylinder head gasket, not common on the 1.8s (unless you've cooked the engine).

 

[mark2004uk]

Well got to Manchester and back no worries its like 45 each way, but did a small trip today and it overheated, steam coming from bonnet, I felt the rad and that was actually cold !!!

 

[mark2004uk]

Well I don't know the first thing about the heater, by that do u mean the radiator? i wanna empty the radiator and re do it a fresh and bleed it all, but I really could do with photos or a video showing were all the pipes are i need to remove etc

 

[bluejohn125]

Whatever happens buy a new thermostat - take your reg. no. and chassis no. to a motor factors (or worst case Halfords) and buy a decent one for £15 - £20. Thermostats do fail after several years and they are easy and cheap to change once you locate them, move any other stuff in the way, and disconnect the hoses. Carefully remove the old gasket from the block (scrape gently) and use a new gasket (should be supplied).

If you're changing the coolant and flushing etc. it's bugger all extra effort to swap the 'stat.

Also check that your rad cooling fan cuts in when the car is idling for a while - otherwise it will overheat.

 

[mark2004uk]

Maybe a daft question, do you bleed the cooling system whilst the engine in running so you have the pressure there?

 

[mark2004uk]

After using my car the other day i WAS walking up my street and I could see a dripping coming from under it, it was kinda in the middle towards the rear of the engine compartment, or that where it looked to be coming from, maybe a cracked pipe?

 

[mark2004uk]

:bang::bang::bang::bang::bang::bang::bang::bang::bang:

Well broke down on motorway, AA said it sounds like timing belt snapped.... sod it... I cant afford the repair im gonna have to get shut :-(

 

[mark2004uk]

So my timing belt going could explain the coolant problem ? as the belt also runs the coolant/water pump, am i right in thinking that?

People think mend or scrap ?

Can i refit myself ?

Is there an easy pdf/video ?

I looked in the Haynes, but they never ever look the same as your car do they..:bang:

 

[bluejohn125]

Congratulations, well done you....

In the last 2 weeks you seem to have made no effort at all to fix the problem, you kept on using the car while ignoring all the warning signs.

You seemed to think it would fix itself, or "the internet" would fix it for you...

It could be that the problem was the coolant pump was seizing, this may have done the timing belt... a garage would have found this if you'd bothered to investigate properly.

Sell the car to someone who may take an interest in it.. you shouldn't expect this forum to help you pretend you're going to fix it yourself. It annoys me when a good useable car is wrecked through neglect and laziness.

Have you considered actually banging your head against a brick wall?

I'm not normally so negative but you don't deserve much sympathy IMO.

 

[mark2004uk]

I have been in the are and looked at pipes etc.. for your information... and you sir are an ass for the response you sent.

 

[Gregovic]

First off, I don't agree with the tone of Bluejohn, but I do kinda agree to his message. Things like a cold radiator while the engine is cooking over are indications of SERIOUS problems. You shouldn't have been driving the car at all. (Even to a garage it would have been better to get a tow) The way he gives his message is not really the best way to do it. But his sentiment of, this could have been avoided, is correct.

No disrespect meant, but if you couldn't figure out an overheating problem I don't think you should be bothering trying to fix this yourself. If the timing belt snapped you will need new a complete head refurbishment. Skim the head, new valves, new cams, new distributor/timing set, etc. Then the head needs to be skimmed, new headgasket, new headbolts and lastly get everything mounted and timed correctly.

This is probably going to cost more than the car is worth if you let a garage handle it.

It's entirely possible a seized waterpump caused the timingbelt to snap. Another possibility is a seized thermostat (which could possibly still work intermittently, explaining the intermittentness of the problem) The overheating of the engine could also have weakened the timing belt (rubber doesn't react well to heat exposure)
How many miles did the timing belt do? And how old was it?