Hi,

I must have a leak somewhere in my coolingsystem, on my 03 4.4. I cant find out where. I replaced the thermostat last winter. I had a lot of trouble getting the heater warm, but thought the thermostat fixed it. It did to some extent, but the weather changed at that time so I never really got a good test of the heater. Now the weather in norway is about to get colder and I can sense its not working to its full potensial. I checked the coolant and there was about a litre missing (from the last time i refilled in march, and have driven 10.000km afterwards).

There is no apparent leak anywhere, but there seems to be airbubbles in the coolant from time to time. I refilled and bleed the system on thursday, and it seemed to be getting real hot and toasty in there for a while. But then is started to disappear. After driving for a couple of days, it seems to be hot for a good while as long as the heater is blowing at very low speed. If I turn up the speed it pretty quickly goes to lukewarm. If I let it stay at lever 1 it blows hot for a while, then colder but then kinda of hot for quite a time.

I opened the filler cap today, and there is correct level of fluids on it.

There is no white smoke etc from the engine.

I had a mechanic take a look at it last winter when I had some stuff done. They pressuretested the system and it appeared to be fine. But they discovered a leak in a gasket by the transmission that they changed. It seemed fine after that. Around that time I had another leak from a broken hose. This hose broke last spring, and have been changed.

There is sometime a weak smell of coolant when I have driven the car, coming from the driverside engine bay. (LHD in Norway), but less and less of it nowadays.

I am open to any suggestions to where to look. I can`t stand the thought of freezing in the winters we have here.

Last edited by MariusRR on 23rd Sep 2014 5:01pm. Edited 1 time in total

Anyone?

I am no expert on the l322 cooling system but spent many hours fiddling with the p38 cooling system and from what you describe my guess is you could have an air lock. The BMW engine is a real pig to get all the air out of. There is also a secondary pump in the system and I am led to believe that the header tank can suffer from hairline cracks that only show when engine is really hot and under pressure - also with replacing the cap on the header tank ?
Just some pointers really

Sandy could be right about the air-lock since all engines (also the later 4.2 SC engine) are quite difficult to fill after empty (mine has been done twice due to two oil/coolant heat exchangers failing).

Another option could be the flaps that direct the air flow into the car. The motors on them don't live forever although I suggest to try to get the air out first. There is another post on here one or two days ago where an indy spent a week to completely bleed the air out and after that the car seems fine.

Found it : http://www.fullfatrr.com/forum/topic26699....t+cold+bmw MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

I will try and bleed it some more then!

By the way, my car has a 140 cap on the expansion tank. Is that correct?

I checked and on the BMW 540i and 740i the M62b44 comes standard with a 200 cap. The BMW 530d (same engine as the td6, comes with the 140). I reckon the cap has been changed during service sometime. But could the 140 cap ble responsible for this weird problem. Its seems the heat of the heater disapperas when there is pressure to the system.

I'm losing coolant to the point where the electric fan is coming on. I've pressure tested the system using a Blue Point testing kit and also checked for gases in the coolant but all is fine.
I have a 140 cap which I assume is the correct one for a td6. There are no water stains anywhere

Where is the coolant going?

On my car there was a leak underneath. A gasket on the gearbox or converter. Didn`t show a leak on the pressuretest, but it you touched it with your hands it poured out. Might be worth a check og search on the forum.

140 is the TD6 cap yes!

Update.

I changed the expansion cap, and the smell of coolant is gone. But still no heat.

The car will blow pretty hot until its warm, but around the time the thermostat opens the heat slowly disappears.

I checked with the hidden menu system and the temp om the engine is 110C after driving for a while. As it should be. But no heat.

I tried bleeding earlier. Not sure if i have enough coolant in the system and if i am doing the bleeding correctly. How do i fill up properly and bleed afterwards?

I love the car but this is starting to feel pretty hopeless. The hot of the car vanishes when its 3 degrees outside and raining and cold Inside. Not many 4.4 in Norway so i'm reluctant to put it in the Shop. Spending 500 pounds on no clear answer would annoy me greatly.

Has it got LPG ?? Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

No LPG no

Oh right, can't help then unfortunately, sometimes if the LPG vaporiser water pipes are fitted wrong they will starve the heater... Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Have you checked the actual temperature of the heater itself. It would mean getting to it but it may be worth pulling the das apart for that. Then also check the flaps if they are moving in the right direction.

I don't know the heating system but if the engine stays warm and there is no valve in the system, then the heater unit should be warm and the flaps are the issue or better the flap motors. So if you can find out whether the heater unit itself is cooling down there is an issue in the cooling system (air bubble etc.) if the heater unit stays warm then the flaps are not working or the flap motors are not working.

If it is engine related than a good BMW specialist can help, since it is a BMW engine

If it is air, then try to find an offroading place (take plenty coolant with) and let the car drive and sit at all angles. Just play for a few hours and see if you can dislodge any air bubbles. If you have to keep filling up with coolant you know your answer . I'm pretty sure that you can find some nice offroading opportunities in Norway  MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

Faulty thermostat?

Car got a new thermostat in march so doubt its that!

Another quick question.

If I put the ignition on II, the fan speed on 2 and the heat on full, should the coolant be circulating allthough the engine is not running? Cause its not. But if I start it, I get a stream of coolant running into the expansion box. For the first couple of minutes its a steady stream, but after that the stream decreases. Is that as it should be?