E46 318i help needed

Scuzi

Scuzi

Scuzi

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I was driving my mum's '99 BMW 318i along a dual carraigeway today when I began to smell burning. I thought it was coming from outside. About 30 seconds later the "low coolant" warning light came on. I kept a close eye on the temperature gauge until I could find somewhere safe to stop. After about another mile, the temperature gauge began to rise. I stuck the blower onto full hot but rather strangely it was blowing cold air :confused:

Anyway, the temp needle went into the red and the red light came on. I had to do another half mile whilst the temp gauge was at max in order to stop in a safe layby.

I stopped and turned the engine off. I opened the bonnet to find water everywhere and steam churning out of the radiator cap. I called a mate who brought out a drum of water. It took about 4 litres of water to fill the radiator again. This lasted for about 3 miles when steam began to churn out from the bonnet again. It wasn't until I stopped the car that water began to leak again.

From what I can see there are two possible causes:

1 - There is a leak in the coolant system and when the coolant runs out, the engine overheats.

2 - Something is causing the engine to overheat which is in turn boiling the coolant and causing it to overflow.


Can anyone make any suggestions? The car is sitting outside the house with a puddle underneath the passenger side front wheel.

Time for a new car methinks...

Thanks :)
 
blocked radiator, headgasket? both would cause over pressurisation and overheating, either that or it sounds like it might be a leak if there is a puddle below it unless the high pressure has caused a leak.
 
Rich1988 said:
blocked radiator, headgasket? both would cause over pressurisation and overheating
Click to expand...

It definitely appeard to be over pressurising. The water has sprayed all over the engine bay.

I don't know if this helps but despite efforts to warn my mum, she brought the car to a local mechanic to get it serviced. After the service, a very slow leak developed in the coolant system, i.e. about a litre of water every couple of weeks. She brought it back to this mechanic (who I know to be clueless) who put some radweld into it. It appeared to fix the slow leak. This was about 2 months ago.

Is it possible the radweld that had set in the leak has dislodged and caused a blockage?
 
Sounds like its leaking, water is being replaced by air and collecting in the heater matrix, hence no hot air.

A hose with a hole in will spray over the place, the pressure from the hot water and water pump running will do that in normal operating conditions, its not a sign of coolant system with a pressure issue.

Radweld is unlikley to do any real problems, you have to have very narrow water ways to get blocked by that stuff and if it does the diameter would mean they are not critical. If you have a puddle find out where its coming from.

Sometime is can just be the pressure relief spring in the radiator cap going lazy and letting the water out before it should and a new cap can fix the problem.
 
Tom|Nbk said:
Would it not be cheaper / more cost effective to fix this one. I can't imagine it being a huge uber expensive fix unless the head gasket is now ****ed
Click to expand...

In the past 6 months the following has been done:
-New alternator
-New electrics after it continually blew headlight bulbs
-New rear suspension
-New brake pipes
-New air con compressor
-Rear diff overhaul
....amongst a lot of other smaller faults.

It worked perfectly for 2 years but about 6 months ago something snapped and it seems to have set off a chain reaction. It has cost over £2k in repairs in 6 months.


On another note, what would the car be worth as a trade in?
It's a '99 318i SE, 120k, average/good condition, 1 year MOT and new tyres all round.
 
Scuzi said:
It definitely appeard to be over pressurising. The water has sprayed all over the engine bay.

I don't know if this helps but despite efforts to warn my mum, she brought the car to a local mechanic to get it serviced. After the service, a very slow leak developed in the coolant system, i.e. about a litre of water every couple of weeks. She brought it back to this mechanic (who I know to be clueless) who put some radweld into it. It appeared to fix the slow leak. This was about 2 months ago.

Is it possible the radweld that had set in the leak has dislodged and caused a blockage?
Click to expand...

could be that the leak of coolant could have caused it to overheat and acaused hgf as a side effect, but yea as you say soem rad weld could have constricted/blocked a coolant pipe causing pressure to build up and bursting at a weaker point in the system, if the car still has the corerct level of oil and wasnt run really really hot for a prolonged period I wouldnt have thought the head gasket would have failed though.
 
Since you've overhauled a lot of the other stuff it might be best seeing if you can fix this problem before thinking about binning it in. Still I agree you have to draw the line somewhere.

Which reg is it?

V?
 
I was worrying about the head gasket. I ran it on the max of the temperature gauge for about 2-2.5 minutes. I'd have stopped right away but I was in the middle of an unlit dual carraigeway, on a long sweeping blind corner and at a spot where people frequently do 80-90moph. I wasn't stopping for anything :p
 
Tom|Nbk said:
Since you've overhauled a lot of the other stuff it might be best seeing if you can fix this problem before thinking about binning it in. Still I agree you have to draw the line somewhere.

Which reg is it?

V?
Click to expand...

My mum has no confidence in the car at all now and as she relies on it to get to and from work she wants rid of it.

Reg? CKZ :p

We work on a different system here in NI. I think it was registered mid-99.
 
Keep forgetting you're in NI :p

Ok Whatcar says...

BMW 3 Series Saloon (98-07) 318i (116bhp) 4dr 1999 (V )120,000 miles

Dealer £3,145
Private £2,735
Part exchange £2,680
Trade £2,475
Cost new £20,210

Gives you some idea anyway :p
 
As my mum needs the car to get to work in the morning, she called the RAC out.

Where the hose that comes from the engine connects to the top of the radiator has broken off completely. The actual part of the radiator which the hose fits over has corroded to nothing and has blown off completely.

New radiator time :(

How much should a new radiator plus labour cost?
 
Scuzi said:
As my mum needs the car to get to work in the morning, she called the RAC out.

Where the hose that comes from the engine connects to the top of the radiator has broken off completely. The actual part of the radiator which the hose fits over has corroded to nothing and has blown off completely.

New radiator time :(

How much should a new radiator plus labour cost?
Click to expand...

Was about to say, my friend had the same problem and we had to keep starting and stopping every half a mile or so. He never filled the coolant up in 2 years so the radiator had gone, any water going in just went straight through.

He had it replaced at home for free as it was under warranty, I would hazard a guess of £150-250? To include fitting as well.
 
Tom|Nbk said:
I can't imagine a few minutes would have caused much harm.
Click to expand...

I can. A few minutes in the red is unfortunately all it can take to cause damage :(

A new rad at an Indy should run to £200-£250 tops. The symptons you described (No hot air, temp rising, etc etc) are ones you'd get if you had a rad with a hole in it leaking out coolant :)
 
I forgot to mention. I asked the RAC guy about how the HG might fare after a couple of minutes. He had a quick look and said that it 'appears' to be fine.

I'm going to call around tomorrow to see if I can get anyone to do it ASAP for a reasonable price.

What are your thoughts on reconditioned radiators? They appear to be quite a bit cheaper and since we're planning on getting rid of the car soon-ish it should do the job....no?
 
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