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Discussion Starter #1
Hello all :thumbsup

I had a slow water leak of coolant, so I took it in to be fixed last week. I also took a new water pump, thermostat and thermostat housing-not sure when they were last done so thought I may as well while its in. All done, and he said there was evidence that there had been some sort of leak from the water pump, but he couldnt actually find one at the time.

So it was refilled with coolant and off I go-after telling me I need to check the level of the coolant as even after bleeding there could be air in the system. I have checked and filled it up twice-but I am getting worried there is a leak.

However, someone else told me that this can happen for a while-I guess my question is should it have settled by now, or is it normal for the settling of the coolant to take a few times?

If it helps, I have a block sniff test at home and that was negative, and it has never over heating or shown a low coolant level warning.

Thanks

PHil
 

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Discussion Starter #2
Update.

I just went outside and removed the expansion tank cap (level low) and then the bleed screw. when I did that the level in the tank came right up the top.

Whats that all about?

I then did the following priocedure

- with cold car
- top up coolant to proper level.
- leave rad cap loose

This stage bleeds air trapped in the heater system.
- turn on ignition switch to position 2 (no start)
- set temperature selectors on the climate control to max temp.
- manually set the fan speed to low (lower end of speed range)
- start engine (check that climate settings have not changed)
- after 5-10 seconds of running rev the engine 3-4 times to about 2500 RPM - hold
there for about 5 seconds each time.
- shut off engine (should not run for much longer than about 30 seconds - you just want
to shut if off before it starts to generate any heat and expand the coolant).
- inspect the coolant level and top up again if necessary.
- tighten the coolant fill cap.


BUT I LEFT THE RAD CAP AND BLEED SCREW OUT by mistake-when revving the coolant sprayed everywhere. I then bled the systemby topping up until fluid ran clear. I did get some air coming out!

Worth noting however, is that the fluid that came out is very dirty, where as the last few times I have bled the system it was the nice new coolant.

Also, for the first time EVER, the temp went above the middle...
 

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Had the same problem before christmas when I flushed system and put new anti freeze in. I had an air lock and could not get rid of it no matter how many times I bled it. Ended taking to local garage, they bled it again and it took another 3 litres of coolant to fill the system. Still think theres air init now as heaters blow cold when stationary at traffic lights and go hot again when I;m on the move. Temp gauge bang in the middle though. Dont drive if the needle is heading towards the red.
 

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Discussion Starter #4
So when the tank level rises when I remove the cap and bleed screw, is that an indication of air in the system?
Thanks again!
 

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How to bleed the cooling system.
1.Jack the front of the vehicle up onto stands as high as possible,
2.Turn the ignition on to Aux 2, Engine OFF, heater on fan setting 1 and temperature fully hot,
3.Remove the rad cap/expansion cap,remove the bleed screw from the radiator and IF you have them the bleed screw(s) from the thermostat housing/top hose, return pipe or EGR thermostat.
4.Fill the radiator/expansion tank up and keep pouring till there are no more air bubbles coming out from the bleeds, using a funnel that fits tight in the expansion tank neck and filling it full of water will help push any troublesome air out, when good you can then install the bleeds and tighten down(don't snap them),ensure the rubber O-rings/seals are still on the screws/on the bleed holes.
5.Suck some water out so it's not full to the brim, start the car up and check coolant shoots out of the small hole on the inside of the expansion tank neck when the revs are held up, if it does then replace the cap and then run the car up and check for heat from the vents when the car is warm, then carry on and check if over heating still persists. You may have to bleed troublesome cars again afterwards.(but very rare).
6.If all is good then check the water level again in the morning when cool.

or

Ignition on, heater set to hot, bleed screw out.
Pull the top hose off the radiator. Pour coolant SLOWLY down the rad hose a litre at a time. When the coolant is building up in the hose, hold it above the level of the rad hose stub and keep adding it. When coolant starts to dribble from the rad, refit the hose. You may find that coolant starts to overflow from the rad cap orifice - if it does, just screw the cap back on. Once you've done that, the engine and radiator are full of coolant - the little air pockets that might be left will come through the bleed screw
 

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I cant say why the coolant is rising in the tank, but from reading your thread and my own experience I would put money on it you have air in the system and I personally found it a barsteward to get out, so mine went to the garage he bled it a different way to how I'v been told on here but I watched(heard) the air come from the bleed screw on the thermostat housing and over 3 more litres of coolant went in.
 

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Discussion Starter #7
Thanks for all the replies.

I have bled the system using the method above a few times.

Its in the garage now as its having a new "donut guibo thing" fitted tomorrow, so I have asked them to re check everything and see if they can bleed it better!
 

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Had the same problem before christmas when I flushed system and put new anti freeze in. I had an air lock and could not get rid of it no matter how many times I bled it. Ended taking to local garage, they bled it again and it took another 3 litres of coolant to fill the system. Still think theres air init now as heaters blow cold when stationary at traffic lights and go hot again when I;m on the move. Temp gauge bang in the middle though. Dont drive if the needle is heading towards the red.
i ve got this exact problem, how did you sort it out?

cheers

Rigy
 

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Sorry to jump in here but i have what i think is an airlock in my system which has been there months,

one day i check coolant level after 30mile trip and the level is raised,

next day check it and its down cant find any leak anywhere can someone point me in the right direction and am i causing damage driving around like this as i havent a clue with cars.

any advice very much appreciated.
 

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Sorry to jump in here but i have what i think is an airlock in my system which has been there months,

one day i check coolant level after 30mile trip and the level is raised,

next day check it and its down cant find any leak anywhere can someone point me in the right direction and am i causing damage driving around like this as i havent a clue with cars.

any advice very much appreciated.
Any cold air blowing through your heaters when it should be warm?

And when you say check it the next day is it a cold car your checking or after a 30 mile trip again?
 
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