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Old 1st April 2010, 23:28   #1
markb63
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Default schematic diagram of cooling system

hi , does anybody have a diagram showing the directional flow of the cooling system ? .
my reason for this is , i have changed my rad and fan ( thanks for the kenlow jules ) cleaned out the matrix removed the engine drain , refilled the cooling system with oat , still not getting red hot air out the heater .
i have also done a mod on the cooling rail , car is not overheating and running fine,but the bottom cooling rail is not getting as hot as it should i think ...
so i now think that the problem lies with the thermostat not allowing the coolant to circulate ?

sometimes the heater blows warmish air on low fan , but i think when its on fast because the flow is not good enough the blower is cooling it down , without the fan on both flow and return on the matrix are red hot .
your thoughts please thanks mark
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Old 1st April 2010, 23:57   #2
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It sounds like an air lock in the heater circuit to me, but I'm intrigued by your 'mod on the cooling rail'. Could that be connected to the problem?

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Old 2nd April 2010, 07:10   #3
markb63
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the mod to the cooling rail was done with silicone hose and two sections of stainless steel with the ends beaded over , my mild steel rail was in very poor condition and xpart said they did not have a stockist any more..... i refilled the cooling system with nearly 8 ltrs of mix and allowing for over spill from bleeding is near as dam the 7.2 .

have read of several posts of fellow members who say they have no air lock but heating is not good , even members who have used the pella.

just thinking that there is a different problem that we are missing , so does the thermostat control the flow round the system . my water pump was replaced approx 39 k ago with belts ...

if everybody thinks its an air lock , i have to take there advice as i have only owned the car for 2 months and most of you have been tinkering with these cars for years .

if thats the case then will hhave to try and get hold of a pella or take a trip to lates , how much do they charge to empty and refill a system ( ball park figure ) cov not to far from me .... i wonder if they are open over the bank holiday , this is doing my head in now
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Old 2nd April 2010, 10:32   #4
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take a trip to lates , how much do they charge to empty and refill a system ( ball park figure ) cov not to far from me .... i wonder if they are open over the bank holiday , this is doing my head in now
Drain and refill no more than half hour using a vacfill.Cars queueing at the moment until end of May
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Old 2nd April 2010, 10:41   #5
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i very much doubt its the thermostat, if it wasnt opening you would certainly know about it, as the engine would quickly overheat. however, if it was stuck open, your engine wouldnt get upto temp. thermostat allows coolant to circulate around the engine once open, nothing to do with the heater matrix. when the thermostat is closed, the water inside the engine and the heating system is allowed to heat up, which is why the heaters should blow warm before the thermostat opens. once to the correct temp, thermostat opens and coolant flows through the engine.

within the dash, there are control flaps, which basically mix warm and cold air so the temp on the atc unit is near enough what is coming out of the blowers. sounds like either the temp sensors is broken or reading wrong, the flap which controls warm is stuck closed/partially open, or the flap which controls cold air is stuck fully open, if there isnt any air in the heating system.
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Old 2nd April 2010, 11:18   #6
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thanks robson, have covered over 300 miles and no overheating or coolant loss , which temp sender ? thanks mark . will keep that in mind thanks lates
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Old 2nd April 2010, 11:39   #7
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thanks robson, have covered over 300 miles and no overheating or coolant loss , which temp sender ? thanks mark . will keep that in mind thanks lates
im not sure tbh, there is a bumper mounted one, however, if the temp on the display between speed and revs is correct or fairly close, it wont be that. there is also a cabin temp sensor, and if thats playing up then it wont be delivering the selected temp on the atc. the sensor is behind the steering wheel at sort of the 7 o'clock position, but i have no understanding of these. apart from the sensor and the air delivery, i cant think of anything else
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Old 4th April 2010, 10:47   #8
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Quote:
Originally Posted by markb63 View Post
hi , does anybody have a diagram showing the directional flow of the cooling system ? .
my reason for this is , i have changed my rad and fan ( thanks for the kenlow jules ) cleaned out the matrix removed the engine drain , refilled the cooling system with oat , still not getting red hot air out the heater .
i have also done a mod on the cooling rail , car is not overheating and running fine,but the bottom cooling rail is not getting as hot as it should i think ...
so i now think that the problem lies with the thermostat not allowing the coolant to circulate ?

sometimes the heater blows warmish air on low fan , but i think when its on fast because the flow is not good enough the blower is cooling it down , without the fan on both flow and return on the matrix are red hot .
your thoughts please thanks mark

you most certainly have air in the system , when you refilled the system did you have the heater set high?. ito get of air and gunk from my system i un did top and bottom hose and ran a hose pipe through top hose allowing water to go right through system ,you wouldnt believe the muck that came out .. then filled it up and bleed it .you will need someone to top up while you bleed it as it takes a while for the air to escape .the lower the level gets the more air you will get in system .. mow i got a nice hot heater and no more over heating issues or hoses splitting cos of the prusse build up due to the air in system and coolant not being able to circulate around the system ...remember bleeding the system is not about letting the over fill of of coolant out to obtain the right level of coolant .to get rid of all the air it can take you up to an hour .when the air was all out my car the coolant flowed out the bleed value in one movement not slowing and speeding up and slowing again ..
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Old 4th April 2010, 11:12   #9
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the cooling system has been bled that many times i have shares in oat .

the matrix has been out and descaled , brand new rad , new moded cooling rail . the heater motor is working fine on all speeds , coolant level stays the same when checked at cold , deff sure the correct ammount 7.2 ltrs has gone in measured , system comes up to temp ok and stops at just a fraction under 9 oclock and stays there even in traffic fan kicks in , air con was serviced at the same time as new rad and kenlow fan and works fine ............. , i have extended the expansion pipework to above the hight of the bonnett the other day when refilling the system as a gravity system fills better the more head hight there is ...... the only thing it can be is an air lock but i just cant believe it the temp on the flow and return of the matrix is red hot not done a temp test as its ****** hot . will run her for a few weeks and if it is an air lock hopefully it will make its way to the highest point expansion tank ........... the air that is been blown out is ok , but not banging red hot. if still the same in a few weeks will have to invest in a pella and try that ........... ah well at least the weather is getting warmer and my air con is a1
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Old 4th April 2010, 19:44   #10
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Quote:
Originally Posted by markb63 View Post
the cooling system has been bled that many times i have shares in oat .

the matrix has been out and descaled , brand new rad , new moded cooling rail . the heater motor is working fine on all speeds , coolant level stays the same when checked at cold , deff sure the correct ammount 7.2 ltrs has gone in measured , system comes up to temp ok and stops at just a fraction under 9 oclock and stays there even in traffic fan kicks in , air con was serviced at the same time as new rad and kenlow fan and works fine ............. , i have extended the expansion pipework to above the hight of the bonnett the other day when refilling the system as a gravity system fills better the more head hight there is ...... the only thing it can be is an air lock but i just cant believe it the temp on the flow and return of the matrix is red hot not done a temp test as its ****** hot . will run her for a few weeks and if it is an air lock hopefully it will make its way to the highest point expansion tank ........... the air that is been blown out is ok , but not banging red hot. if still the same in a few weeks will have to invest in a pella and try that ........... ah well at least the weather is getting warmer and my air con is a1
have you tried taking the cap off the header tank, then squeezing the bottom hose near the rad, then work your way up squeezing all the water pipes you can get to?
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