5-Series (E12,E28, E34, E39, E60)Chat relating to the BMW 5-Series of all generations. Specific models include: BMW 518, BMW 520, BMW 520i, BMW 530i, BMW 528i, BMW 530i, BMW 518i, BMW 524d, BMW 525i, BMW 525e, BMW 528e, BMW 540i, BMW 535i, BMW 520d, BMW 525td, BMW 525d, BMW 530d, BMW 525i/xi, BMW 530i/xi. (BMW 5-Series Forum)
The heater on my newly purchased e34 appears not to be working in that the air that it blows into the car never really gets past 'vaguely warm' regardless of where I set the temperature, blower or individual vent flow regulators. It is the same for both sides of the car.
Is this a common problem with 5s? If so what is likely to be at fault?
right, I have just done a few more tests on the car:
First I checked the coolant level, it was very low, needed over 2 litres of water to top it back up to full.
Once I had done that I let the engine idle for a bit and as soon as I turned the key in the ignition the temperature guage shot right up to the very top way past the red line. Obviously the engine cannot have been that hot straight from startup.
After a couple of minutes the temperature fell right down to just under 1/4 and then it rose again to about 3/4, eventually it settled down to just under a 1/4 after 5 minutes.
The temperature coming from the heaters on full was again 'vaguely warm', but if I increased the revs to about 3000rpm the air coming from the vents became noticeably hotter almost instantly, and when it went back to idle again the temperature again dropped.
Another thing that I noticed was that the radiator fan came on straight away, should this only come on once the engine has reached its' operating temperature and needs to cool?
Anyone got any bright ideas as to what the problem could be then? All responses very much appreciated!
1. The fact the antifreeze is low means a leak somewhere in your system. I would check for that first. Beware A leak does not always mean you going to see antifreez under the car or on the floor of your garage. While at it try not to use straight water in you system; you will be inviting corrosion and rust.
2. When you added the 2 liter of water you thought you filled the system up; you did NOT! Air still trapped in the system will prevent a full/complete circulation of water/antifreeze and that is why you had an instant overheating (the gauge shot up to red while idling) this is telling something. I will send u more info. on how to do it
Now. You have to bleed the system by getting the air out of it and this is how u do it. Looking at your engine you will see 2 pastic screws with rather a large philips head the first one sits right after your thermostat housing and the second one sits to the right of your radiater cap. start up open, the cap (when engine cold only so no one gets burned) when the pressure start building up (you can test by pressing on the big hose or looking inside your reserv. you will see a tiny stream of antifreez dropping this means your water pump just kicked in) slowely loosen the screw if air present you will notice it escaping (as bubles and/or hissing air)keep it open until u see solid antifreez coming out of the screw with no air no bubles. the same must be done for the second screw (next to the cap) . Next top of with antifreez and you will be on your way
let us know
thanks for the advice BillB! I will have a go at bleeding the system later today.
When the temperature guage shoots up at the beginning it is definitely giving a false reading because it does this before the engine has been started and when the engine is stone cold. Over the next 5 minutes it slowly drops down to what looks like a correct reading just above the blue zone.
One other thing - the overflow tube from the top of the coolant filler tank drains straight down on to the road via a rubber tube, is the right? It seems a bit odd to me.
well I usually tend to disconnect one of the battery terminals for about 2-5 minutes and then reconnect; it works for me in the sense of reseting many electronic stuff including gauges. But the high temp (the red light) is NOT FALSE when engine is running be carefull as a matter of fact the car is TOO HOT simply because the engine is starving for liquid whether it is water or antifreez. Without bleeding? The system is paralyzed by air (no circulation) so don't keep it running if you see the red light shut down immediately. you may well blow the head gasket if you run it for too long.
Tip: when working try NOT to lean with your hand on the Radiater neck; it is plastic and breaks easy!!!!!
I just bled the system, although I could find only one bleed screw which was a massive plastic bolt head with an allen key indentation in it on top of the expansion tank at the back of the engine bay, I only just had a spanner big enough to get round it!
I couldn't find the thermostat in the engine at all, I think I found what I thought the thermostat was, but it didn't have a bleed screw or bolt on it, so I'm not so sure now.
I will try the trick of disconnecting the battery and see if that resets the system.
Thermos usually sets in the front of engine not the back if you follow the upper hose from the radiater it ends at the thermos housing but you are making the right decision by going to a mechanic to do it at least for safety reasons; I think it is worth the investment for now ask him watch him you'll need the info. for the future
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