help need!!! over heating engine..

[y2kfarrell]

3 weeks back i was making a trip from A to B about 90miles long got there fine no hassle. However on the return trip i was passing out on the motorway doing about 70 when anytime i went to speed up the car spluttered and didnt seem its self. Now i had been having trouble with a coil pack so at first i taught it was that again.
On looking at the dash i noticed the temp needle was way to high. being on the motorway i couldn't pull in so i put the heat on full blast and sure enough the needle dropped and the car was fine.
I pulled in when i had the chance and notice the coolant bottle was empty so i topped it up with water, but to no joy.
Next morning i got coolant and filled the bottle to the mark and put a drop in the radiator.
On doing the same journey again the next day it started over heating again. i pulled in and notice the coolant bottle was full way over the mark so emptied some out. The car would over heat if i turned off the heat inside the car.
So having the heat on cures the problem but im getting cooked alive inside the car. But again on the way home the problem went and was gone for two weeks but it started over heating on my way home this morning so the heat had to go back on in the car:annoyed::annoyed:

I dont know what it could be as i dont fully know the workings of the radiator in the car.
The fan works, their is heat coming on in the car so that would tell me there is water circulating in the rad and that the thermostat is opening, So is it a sensor faulting somewhere?????

Any ideas would be of great help from ye wise people out there:thumbs:

 

[StarletRick]

it will be a rad problem by the sounds of it. overheating on the mway just doesnt happen if water is flowing through the rad.

the heater matrix for the inside car heat is different from the radiator mate. its up inside the dash.

let the car warm up fully until the fan cuts in and then feel the lower rad hose. it should be hot. if it isnt then theres no circulation in the rad so id suspect the thermo (if it was the pump, you have no heat inside the car).

could also be an airlock in the system from when you let it run low. that can stop water flowing round the system aswell.

to cure that, take the rad cap off, have the engine running and pump the lower rad hose with your hand filling the rad as you go.

hope this helps mate and you sort it soon.

 

[Nicely]

There is an air relief bolt specifically for clearing air locks out of the water system (see LC14 in the workshop manual). Remove this bolt then keep filling the rad until water starts squirting out of the relief hole. Replace the bolt and top the rad. The bottle should only be half full.

If that fails, change the themostat.

 

[krisrt]

id deff say the thermastat m8 had exact same prob/symptoms on my fiesta and in the end found the thermastat wasnt opening.

 

[StarletRick]

oh i didnt know there was a releif bolt.

where abouts is it nicely?

 

[Nicely]

On the top of the outlet pipe (top right off the rad). Bleed the air first, particularly if you've changed the water and never touched the air relief bolt before...

 

[y2kfarrell]

Cheers for the input folks,
Airlock is what I initially taught. And have tried with the cap off and running the car till the temp reaches the heat to open the thermostat hoping it would sort an airlock but no joy.
Not that im doubting anyone I wouldn’t be asking if I knew all the answers put if it was the thermostat would it not cause havoc with the car. I sat in traffic today for an hour and it was fine turning the heat on and off as I wanted it temp needle never moved. But if I do a 40miles+ of mileage it starts the over heating crack

Nicely
For the air relief do I need the engine running are just open it, drain a bit and lock the nut and top up again.????

Would drain the rad and start a fresh if I could only get under my car. Have no where to work on my car at the moment until next week.
Will try the air relief, if not will drain rad. All fails will get new thermostat only 20euro for one…

 

[Nicely]

The air relief bolt is at the highest point in the water system. If there's an air lock, it will naturally sit here. Once bled, its very unlikely you'll have more air.

If you're going to drain the rad, change the thermostat. You'll only have to drain it again...

 

[y2kfarrell]

Going to finally go at the car tomorrow,
going to change the thermostat but when it comes to refilling the radiator and unairlocking it. Is it easy to do.
By that, I had a bmw and to unairlock that the car had to be at an angle an took a few attempts.
Also was wondering is the fan meant to be on once the car is started,
or is the fan only meant to engage when it reaches the right temp. (mine starts with the car)
Again had this problem with a bmw where the copper coupling was F**ked and wasn't expanding locking the fan on when it heated.
Thats why i was thinking it was the fan not engaging causing it to over heat on a long journey.
Anyone else ever have a problem with there fan

 

[DeanS15]

the viscous fan should kick in when you start and calm down after a few seconds. as for air locks - its pretty simple mate, drain the coolant, do the job, leave the bleed screw off and slowly fill the rad. when the coolant starts to overflow from the bleed screw put it back in and top up the rest of the way. that should do it, but run it up to temp and watch the needle, let it cool and re-check the coolant/top up. also half fill the expansion tank between the full and low marks

 

[y2kfarrell]

viscous fan
Thank you i couldnt for the life of me remember the name of them.
I`ve a feeling thats what the problem is,
But i am hoping its just an air lock r thermostat. ill do it all tomorrow and see what happens.
Thermostat isnt easy reached, ah well thats the joys of motoring!!!!!

 

[Matt_S]

The viscous fan runs all the time Dean.

Check the Rad for cold and hot patches. If you feel a massive difference, then it may be that part of the rad is blocked. I take it there is actually enough water in there? Did somebody say Split tubo water pipes? :wack:

 

[DeanS15]

yep, i meant that when you first start the car it flys into life and then settles to a constant spin

 

[y2kfarrell]

The saga continues
Went to drain the rad only to find that the plug is worn :annoyed::annoyed:
So i wasnt able to open it. so i bleed it and took it for a rip came back checked it only to find that only 1/3 of my radiator is hot the rest is cold so its blocked. also noticed a few feathers stuck to it must have mangled a bird one of the days.
Wondering what to do now.
Cant open the draining plug so do i disconnect the outlet pipe and let it drain off that way and will flushing the system unblock it.
Or will i have to buy a new rad

 

[DeanS15]

i've got a perfect rad mate off a 38k mile car - its spot on. how about 40 quid?

 

[y2kfarrell]

Cheers lad.
Dont know yet if i need a new rad yet r if i can flush out the old one but ill keep you in mind if i do.