Worst fears: 318ti overheating

[paww 1]

Just bought my car last weekend, took it for first proper extended drive (about 200km) over highways and hilly roads, all was going well until I was driving back in the city and in traffic temp gauge quickly shot up in to the red and could see steam coming out of the front of the bonnet.

This was about 1 min away from my house so limp it home. (writing this now, in hindsight probably not the best choice)

Now it's stopped, I'm waiting for it to cool down to take a look at it.

Something is leaking out of the bottom, looks like water or coolant.

Has anyone got any suggestions of my first things to check or do?

I annoyingly didn't check coolant before I left this morning but it was only in for a service on Weds so had everything topped up so assume there's something else going on.

edit/

I'll most likely take it to a garage on Monday but was thinking what can do I check or do in the mean time?

Cheers

Edited December 5, 2015 by paww

[LemonHunter 583]

The fluid leaking if coolant is probably from overflow... or a part of the coolant system cracked and broken. (Google it, M4X motors are famous for shitty cooling systems)

Things I do when this happens;

Check how much coolant is left in system

Check aux and/or viscous fan work

Compression test if you have a kit (open top radiators you'd rev it and watch for bubbles)

Check for white/emulsified engine oil

Driving or limping with water temp in the red is a bad call.

Remember its WATER temperature not engine temperature, so if your system manages to dump all its fluid AND the needle hits the red it's very very bad juju.

Edited December 5, 2015 by Charlie F.

[paww 1]

The fluid leaking if coolant is probably from overflow... or a part of the coolant system cracked and broken. (Google it, M4X motors are famous for shitty cooling systems)

Things I do when this happens;

Check how much coolant is left in system

Check aux and/or viscous fan work

Compression test if you have a kit (open top radiators you'd rev it and watch for bubbles)

Check for white/emulsified engine oil

Driving or limping with water temp in the red is a bad call.

Remember its WATER temperature not engine temperature, so if your system manages to dump all its fluid AND the needle hits the red it's very very bad juju.

Thanks for the reply Charlie, never had a car overheat so don't even know what to expect.

I was told by the garage who did the service where to fill coolant too if I needed to fill it, at the time he showed me it was at the line that was approx half way up.

I think it still had coolant (questionable how much) whilst I was limping it back home because it was only once I stopped that I was able to notice that it was leaking out of the bottom of the car.

Just went to have a look at it, the engine is still fairly warm to the touch so I think I'm going to have to leave it until the morning now to check on oil and coolant. (guessing no coolant left).

I don't have any kits or tools to test compressions sadly.

I did a bit of reading to find out about testing aux fan and it supposedly should come on if the ignition is on and the AC is on? this didn't happen for me. Also read something else to suggest I could try and test it by bridging connections across the fan switch connector, I only have one weedy bit of wire which didn't seem to do anything so I'll have to wait until tomorrow to find a shop open to grab some wire to test that. Any other suggestions for how I could test the aux fan?

Curiously something I hadn't noticed (mostly because I've not had the bonnet up with just the ignition on) there is a terrible whine/buzz which I'm guesing is from the alternator. Normal?

One thing I forgot to add, when i first turned parked the car up after it overheated there was a bit of a knocking noise (not like engine knocking but something similar?) I could hear from under the bonnet whilst I was still inside the car.

The ironic thing for me is, ran OK in similar temps last weekend when I took it for a 70km spin (very little to no traffic though) however yesterday I bought breakdown cover and today I picked up some coolant. Now it overheats!

Edited December 5, 2015 by paww

[Rubix 434]

As stated -

Inspect and replace anything plastic in the cooling system (Water pump, thermostat housing, any pipes/fittings etc) as unless you have proof that this has been done then you need to treat it like it hasn't been. Cooling systems on e36's are terrible, bmw used a lot of cheap plastic parts that fail, however they later revised the parts with metal/alloy (such as thermostat housing and water pump impeller).

I'd not take it on a road trip until you confirm that you won't have any trouble with the cooling system.

Replace everything.
If it's overheated it may be toast - alloy head so they tend to warp when they get too hot - even before the temp gauge hits max as it doesn't keep up with the temp.
Time for a complete overhaul of cooling system, provided head isn't damaged.

[paww 1]

As stated -

Replace everything.

If it's overheated it may be toast - alloy head so they tend to warp when they get too hot - even before the temp gauge hits max as it doesn't keep up with the temp.

Time for a complete overhaul of cooling system, provided head isn't damaged.

This is a big thing for me to consider as I don't have the tools or experience to do it myself. That's why I'd been seeking advice how I could check things along the way.

Water pump was replaced and the thermostat and rad fan were checked in September.

Took the car in for a service last week when I got the crankcase seal replaced (after having had the oil filter checked) and I did asked for him to check whatever he could in terms of cooling system, specifically those plastic tubes/pipes. Which apparently looked OK.

I guess I'll just have to take it to the garage and pray they don't fleece me if it's that extreme.

---

On a side note, garage is like 1km away. If coolant is topped up is it safe to nurse down to the garage?

Edited December 5, 2015 by paww

[Docile 64]

if you had proper coolant in the system, when it dries and cools off, usually it would leave a white residue. could be a number of things. checked the waterpump again? burst hoses?

[paww 1]

if you had proper coolant in the system, when it dries and cools off, usually it would leave a white residue. could be a number of things. checked the waterpump again? burst hoses?

Thanks, I'll definitely keep that in mind when I check coolant levels and oil tomorrow.

[Docile 64]

 

Thanks, I'll definitely keep that in mind when I check coolant levels and oil tomorrow. 

Yeah just track it down from where it is leaking. Follow the leak basically. have had quite a few from the smallest hole on a hose to the reservoir bottle blowing up lol.

Sent from my SM-G900I using Tapatalk

[LemonHunter 583]

Times when you replace a part of a system, and then that system has a problem, i look to the most recently replaced component in that system.

With the water pump, altenator and power steering driven by that one belt, if the belt was loose or worn it might not drive the pump well

[paww 1]

Times when you replace a part of a system, and then that system has a problem, i look to the most recently replaced component in that system.

With the water pump, altenator and power steering driven by that one belt, if the belt was loose or worn it might not drive the pump well

That's a very good point and not something I'd considered!

I do have some receipts for work done this year to suggest that two new fan belts were fitted, there was a comment in there about the a/c belt showing signs of cracking. Is there another belt that I should be looking at?

Thanks for your comments guys, the more I know the hopefully easier it'll be to know what's gone wrong.

Be interested to know if my observation about the fan holds up.

Edited December 5, 2015 by paww

[Docile 64]

take good pictures and post.

if you can, remove airbox and other things in the way so you can have a good look. most problems, depending on your backyard grease monkey skills can be fixed without going to the local mechanic.

as i said trace the coolant leak, if that fails

first things to check :

drivebelt system / pulleys

reservoir

reservoir cap

hoses

waterpump

radiator

think that's all of it. might be lucky and just be a hose

Edited December 5, 2015 by Docile

[paww 1]

take good pictures and post.

if you can, remove airbox and other things in the way so you can have a good look. most problems, depending on your backyard grease monkey skills can be fixed without going to the local mechanic.

as i said trace the coolant leak, if that fails

first things to check :

drivebelt system / pulleys

reservoir

reservoir cap

hoses

waterpump

radiator

think that's all of it. might be lucky and just be a hose

I've just taken a quick look, car is in covered parking so light still isn't that great but checked coolant and it's still the halfway point it was on Wednesday?

Couldn't see any obvious signs of leaks (or what I could tell were) the belts and pipes I could get a hand too still looked intact and tight.

I have very limited to skills so whilst I know I could confidently take some parts off I fear I'd never get them back on again so haven't attempted at taking anything off.

Whereabouts in the bay would photos be help? I'm not that knowledgeable on where everything is.

[paww 1]

A friend offline is suggesting things too and they're guessing it's the thermostat and should just remove that it and see how it goes, does that sound like a reasonable suggestion?

As I've said, my knowledge is limited so wanted to double check before I do thing

Edited December 5, 2015 by paww

[BM WORLD 1283]

also a common failure on these is the fan temp switch in the side of the radiator .

also the half speed resistor on the fan goes open circuit.

half speed should come on at at 12oclock on the gauge

on these 318ti with the electric only fan option.

but sounds like you need to get it tested out properly

all the plastic pipes need to checked or replaced .

possibly been driven running hot lots of times and killed the head gasket or cracked the head

[paww 1]

also a common failure on these is the fan temp switch in the side of the radiator .

also the half speed resistor on the fan goes open circuit.

half speed should come on at at 12oclock on the gauge

on these 318ti with the electric only fan option.

but sounds like you need to get it tested out properly

all the plastic pipes need to checked or replaced .

possibly been driven running hot lots of times and killed the head gasket or cracked the head

Thanks Brent.

I had a go yesterday evening at testing the fan, but didn't turn the car over out of sheer fear of what happened with it yesterday.

I'd read that if the AC is on the fan should come on straight away, which it did not. Also you can apparently bridge connections across the fan switch connector, didn't have any luck there either (although I suspect using a crappy single piece of wire wasn't enough)

If it's been ran hot before and head gasket or head is cracked I imagine that I need to take the whole thing apart to see that right? (definitely out of my skill set)

[paww 1]

also a common failure on these is the fan temp switch in the side of the radiator .

also the half speed resistor on the fan goes open circuit.

half speed should come on at at 12oclock on the gauge

on these 318ti with the electric only fan option.

Started it up, no odd noises seemed OK.

Took about 3-4 mins for it to 'warm up' till temp gauge was sitting the middle at 12'clock and then stayed steady for another 5 minutes before I turned it off. - Fingers crossed that means it's not something like a head gasket.

At no point did the aux fan come on despite it reaching temp, also flicked on AC briefly whilst it was still warming up and that did not kick the fan on, although I didn't leave the AC running for very long at all.

I'm thinking I need to find a way to test that switch.

Edited December 5, 2015 by paww

[polley 916]

Multi meter and pot of boiling water

[paww 1]

Tried to test to get the fan turn on without the switch and wasn't able to 'jump' it by bridging connections like this guy did:

Fuse looked fine so I'm a little bit at a loss as to why the fan won't turn on. - Does that mean something more sinister in the harness? Perhaps I did a poor job of trying to bridge connections.

[KwS 2425]

can you spin the fan by hand?

[BM WORLD 1283]

check th efan relays also ,

and unplug the fan and test with a 12volt supply directly

[paww 1]

can you spin the fan by hand?

No, no it does not move freely at all. Should it move freely?

check th efan relays also ,

and unplug the fan and test with a 12volt supply directly

Thanks for the suggestion Brent, sadly I do not have a 12v power supply to test this with. - I'm wondering if what Kelvin said has any bearing on why it isn't working when I try and bridge connections on the fan switch connector?

[polley 916]

Fan should spin freely. Fan is rooted, possibly blew the fuses that power it also.

[BM WORLD 1283]

No, no it does not move freely at all. Should it move freely?

Thanks for the suggestion Brent, sadly I do not have a 12v power supply to test this with. - I'm wondering if what Kelvin said has any bearing on why it isn't working when I try and bridge connections on the fan switch connector?

you have a battery in the car ??? that's 12 volts

[paww 1]

Fan should spin freely. Fan is rooted, possibly blew the fuses that power it also.

Replacement fan it is then! - Fuses were all fine.

you have a battery in the car ??? that's 12 volts

Fair point, didn't even think about that!

If the fan is stuck in place and can't move (gave it as much force as I felt I could w/o damaging it) I wonder if the relay is the problem? - Sadly it's gone dark now and won't get to look at it again until tomorrow. Thanks for suggesting though, common sense went a miss for me there!

[paww 1]

Took it to the garage today, they were able to find a leak on around the thermostat housing, seemed like at the right temp the gasket wasn't working and leaking out water as he said there wasn't any water left in the engine? Which is supposedly why he thinks that when I tried to get the fan to turn on, because it couldn't see that the rad was too hot due to no water it wasn't kicking the fan on? - Car had new water pump put in by previous owner when the garage diagnosed the water pump to be faulty, he reckons that this was wrong and that there most likely wasn't anything wrong with the pump, the car was just leaking out water and then overheating.

I guess I'll have to wait and see, it ran OK and a short burst today but will give it a harder drive over the weekend.