More overheating 1.6 Focus

Well - I posted the other day re my water pump falure and subsequent refitting and then overheating problems.

I drained the coolant again today and re-filled using the Haynes Manual Method (fill up via heater inlet hose and then via header tank, run engine until warm and then keep an eye on header tank) still overheating. The heater hose that runs across the front of the engine got warm but the radiator hoses remained cool. I decided it must be the thermostat - unlikely, but worth a try.

I got a new thermostat and fitted it and thgen filled the system using Tim's advice, fast tickover, very slow fill via header tank. I thought it was better but no, when I took it out it started to overheat again. When I got back I ran the engine in its hot state (it only gets in the red when under load) and felt the rad pipes. The one on the side nearest the thermostat was stone cold, the one the other side was a bit warm but the radiator was stone cold. It seems there is no flow at all - any ideas on what I am doing wrong here? - Could it be a blocked radiator core?

Reply to
oktopusinc
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Something is seriously amiss here- these are generally not prone to airlocking unless you fill them very quickly.

What water pump did you fit ???

It sounds to me like the new pump is faulty and there is no circulation at all.

Does the heater give full output?

Tim. .

Reply to
Tim..

The pump fitted was a pattern part but it does work - I put my finger inside the block where the thermostat housing is (with the housing removed) and could feel the pump imellor rotating as I turned the pulley (which incidently is being turned properly by the drive belt).

I wonder if it is the rad that is blocked as when I first drained the system the fluid was very dark and soiled - now it drains out fine. Either that or some flukey thermostat problem - I might remove it and see if the water flows ok.

The heater gives full output and the tube across the front is hot as well, the return from the heater to the thermostat housing which maybe suggests that the thermostat works - what do you think?

Reply to
oktopusinc

Just a long shot, but did you compare the two pumps side by side to see if the impeller blades were similar in size and pattern?

The reason I ask is that I was in the domestic electronics trade for many decades, and on so many occasions replacement mechanical pattern parts such as VCR idlers, clutches and pulleys would turn out to be totally useless, sometimes for no obvious reason (especially when the two components looked identical side by side) the only real cure being to fit what seemed to be an overpriced original manufacturers part.

It'll probably turn out to be nothing to do with the pump, but if all else fails it's certainly worth at least thinking about :o)

Reply to
Ivan

To be honest.... I'm baffled!!

All I can suggest is you once again slowly refill it with the engine at fast tickover through the heater hose / expansion tank and with as many hoses slack to try and purge the airlock you seem to have!

Tim. .

Reply to
Tim..

So no-one thinks it could be a blocked rad then?

I don't think there will be a problem with the water pump - I got it from a reputable motor factors in the UK and I think they wouldnt sell many if they did not work. I am going to try flushing out the system with a hose next, maybe take off the rad and have a look and then start filling as per tim's advice - I don't think it is head gasket as there is plentty of power there! - It IS a high mileage car....

Paul

p.s. thanks for help so far Tim.. wrote:

Reply to
oktopusinc

oktopusinc wrote: || So no-one thinks it could be a blocked rad then? || || I don't think there will be a problem with the water pump - I got it || from a reputable motor factors in the UK and I think they wouldnt || sell many if they did not work. I am going to try flushing out the || system with a hose next, maybe take off the rad and have a look and || then start filling as per tim's advice - I don't think it is head || gasket as there is plentty of power there! - It IS a high mileage || car.... || ||

Out of curiosity Paul, how did the original water pump fail, did it disintegrate and what were the symptoms?

Reply to
Ivan

Moment A- car running normally, no overheating, but with leaky pump spindle.

~Interlude~ {water pump replaced}

Moment B - poor circulation, radiator apparently blocked...

Unless you poured a cup of cement powder into the cooling system when you replaced the water pump, why would the radiator suddenly become blocked?

By all means remove top and bottom hoses and see if a garden hose runs easily through the rad.

Tim..

Reply to
Tim..

Hi again,

this is difficult as I can only work on the car at weekends. Took the rad off today and flushed the whole system with a hose - it all seems to be working ok. I refilled very carefully - still overheating and radiator hose from thermostat still staying cold so no circulation - out of interest - which direction does the coolant flow in? From thermostat to radiator and then back to engine at battery side?

I suspect that this is a blown head gasket and that it is filling the system with exhaust gasses creating an airlock? do you reckon?

My wife was in the car when the pump failed which was basically the bearing - she reckons the needle on the temp guage never went into the red but I am not sure how closely she would have been watching this - she was on the motorway but pulled off to a stop before all the coolant came out through the pump housing. I wonder whether the head gasket went - finally pushing the pump over the edge, orwhether the pump went and the subsequent overheating caused the head gasket to fail - any ideas MOST appreciated!

Paul

Reply to
oktopusinc

Coolant flows FROM the thermostat housing towards the radiator, also via the small bore hose to the expansion bottle.

Coolant returns to engine via lower hose.

All Foci have overheat protection, if the CHT reports an overheat situation, three things happen in this order:

a) Temp gauge to maximum with red ECU light flashing. Cooling fans both on full speed. b) Engine drops to 2 cylinders alternatively (1 & 3, 2 & 4) max revs will be ~2200rpm. c) If temp continues to rise, the lights-on gong will sound, and ~30 seconds after this, the engine will cut out all together.

I doubt the HG has popped unless you have been very unlucky. This wont stop coolant circulation though.

Are you ACTUALLY sure the engine is overheating- get a thermometer in the expansion tank or rigged up somewhere on the head. The 'stat wont start to open until about 95+ deg C. Fully open at about 104 deg C.- this is hotter than you might think.

CHT's / gauge's going faulty are reasonably common.

Tim..

Reply to
Tim..

Defo overheating - however I have now cured it. You could not get it to overheat at tickover, only under load. I went out half an hour after my last post and the water had gone down in the header tank - I topped it up and tried the car again, hey presto, all is fine - must have been one stubborn son of a bitch air lock!! - thanks for all the help - back on the road with my 210000 mile focus!!!!!

Reply to
oktopusinc

oktopusinc wrote: || On Mar 24, 1:04 pm

|| " must have been one stubborn son of a bitch air lock!! - thanks for all the || help - back on the road with my 210000 mile focus!!!!!

However it's still has a deal of a way to go before it catches up with a good old fashioned clockwork diesel that will run quite happily on 100% sunflower oil! :o)

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Reply to
Ivan

To be honest, 210k on the 1.6 unit is VERY good going- they're not designed to last this long!!

Tim..

Reply to
Tim..

The camshaft lobes are absolutely spotless - I always do a 5000 mile oil change.

Paul

Reply to
oktopusinc

I've been lurking in this thread. Glad you got it resolved.

I feel like mine is just getting broken in at 137,000 miles.

Reply to
Tony Wesley

I got mine at 167,000- its unbelievably good - apart from a few electrical faults and the water pump it has been fantastic. Just got the missus a Clio so the Focus is mine now!

Reply to
oktopusinc

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