M30 overheating, air lock or head...Head gasket gone. Great.

[pictonroad]

Don't be headgasket

Right, I bought my M30 3.5 7 weeks ago, it drove fine, well, no overheating issues anyway, and a clean exhaust. Did about 500 miles with no problems and it hasn't moved since.

Parked it up and went to collect it yesterday, before starting it I checked the oil and coolant, no coolant in the expansion/header tank. So I filled that up and took the bleed screw off.

When I squeezed any pipe the bleed screw hole blew liquid so that bit had fluid in it.

Got about a mile away the temp gauge just went straight into the red.

Pulled over and the recovery man spent ages fiddling with it. We couldn't get any heat into the radiator, took the thermostat out, that was clean as a whistle but to no avail, heaters stone cold.

In the end it was towed back to mine. Are these engines tricky to bleed?

I'll flush the system tonight and try again but I just can't help thinking head gasket...

A little bit of mayo on the filler cap when I checked and last night after the 1st overheat there was steam coming out of the exhaust....

I can't afford a head gasket

[SPADGE]

Headgaskets don't go whilst a car is stationary.
First thing i would want to know is where the coolant went?
Did it start ok or was it lumpy??
After finding the leak you will find M30'd e30's are a pain in the ass to bleed!
Get the header tank as high as possible and backfill the lower hose and then its just trial and error.
Once the heater blows warm your almost there

[pictonroad]

I keep telling myself that the gasket won't go when it's just sitting, but you know how it is, your mind wanders..

Sat here at work just worrying, I need to be there getting the thing in the air and kicking it.

Please explain backfill the lower hose Mr Spadges....

[nickso]

i owned this car before you bought it off simon.

it did this once to me as well. in the end it was just one of the hoses loose. i refilled it, ran it round the block then left it sitting where i would see any water on the ground etc. found the leaking hose pretty quickly and tightened her up. no probs for several thousand miles afterwards.

[SPADGE]

I keep telling myself that the gasket won't go when it's just sitting, but you know how it is, your mind wanders..

Sat here at work just worrying, I need to be there getting the thing in the air and kicking it.

Please explain backfill the lower hose Mr Spadges....

I wouldn't worry too much mate i've had loads of probs bleeding these things in the past and havn't as yet had to replace a headgasket.

Undo the jubilee clip holding the bottom hose (left) to the thermostat housing and slowly fill it with coolant until its full. Put the hose back on without losing too much coolant.
Do the same the other side if necassary.
Run the engine with the heater on and the header tank as high as possible and the bleed screw loose and see what happens.

[Ziggy]

They can be a pain to bleed for sure. But mine turned out to be the headgasket in the end...

[pictonroad]

cheers, fellas..

I'll nip home at 3 and get started, may be back on for advice!

[pictonroad]

They can be a pain to bleed for sure. But mine turned out to be the headgasket in the end...

how much £ was it to change?

[SPADGE]

They can be a pain to bleed for sure. But mine turned out to be the headgasket in the end...

Was this on the engine i sold you mate?
I thought you did the gaskets before fitting it?
That was almost certainly on its original one if not.

[charlE30]

how much £ was it to change?

Did a mates M30B35 H/gasket and it was around £70 for the full gasket set and head bolts, then another £20ish in fluids. If you do end up doing it be careful not to break the plastic chain guide (like I did ) as then a fairly simple job becomes a right PITA.

Good luck

[pictonroad]

Well, did as suggested and hopefully it worked, I got heat out of the heater anyway which is a definite improvement on Monday..

Left it dry overnight to set the thermostat liquid gasket, going to fill it with coolant and stick a tin of radweld in to be safe...

[pictonroad]

only got a mile down the road, given up, it's in the garage now.

[zimmerbimmer1]

My 535i is losing coolant to somewhere uses around 1 litre to approx 600 miles .

Since fixing the wiring a short in the wiring I know have a fully working heater that gets nice and warm, the
only downside is when it is on and blowing hot air there is a trong smell of antifreeze. when heater switched off and temp set to cold no smell what so ever. puting rad weld in as I think there may be a leak on the heater rad.

[pictonroad]

Garage has phoned, it's the headgasket.

£450 to fix, I've had the car running for one week, what a great f**king purchase.

Will probably just punt on for parts, can't afford to pour money at a basket case motor.

[Ziggy]

As charlE30 said, it's about £70 for the bits - do it yourself!

[danman2k]

can prob get that fixed around here for £250, that was the quote for my old rover. was nothing wrong with the head gasket but they always said that no matter what qas wrong with it, being a rover.

[Chase007]

Yeah do it urself if u still dont get anywhere u still can break it!

[pictonroad]

I haven't got the ability or the time unfortunately. No idea about timing engines and stuff like that.

Bloody car.

[Ziggy]

It's nuts & bolts - no need to do the timing. Got a good guide that I'll dig out for ya in a sec

[Ziggy]

Here you go:

http://www.bmw7resource.co.uk/TechDocs/ ... ent%20.pdf

[richard-the-nutter]

can prob get that fixed around here for £250, that was the quote for my old rover. was nothing wrong with the head gasket but they always said that no matter what qas wrong with it, being a rover.

haha to true

[pictonroad]

hmm, well now, as the garage is starting to quote £7-800 I may have to have a go myself!

[pictonroad]

Thanks for the guide Ziggy,

Anyone got a Bentley on CD or a link?

[pictonroad]

Just read that guide, waaaay out of my league.

"The engine should now be rebuilt as it should be run for 25 mins.... .... and the final angle tightening sequence of 35 deg completed using the appropriate bought or home made tool."





Anyone down south want to earn £300?

[Ziggy]

All that means is put it back together, run it for 25mins, then turn the head bolts 35degrees! Do it...

[murran]

Just read that guide, waaaay out of my league.

"The engine should now be rebuilt as it should be run for 25 mins.... .... and the final angle tightening sequence of 35 deg completed using the appropriate bought or home made tool."





Anyone down south want to earn £300?

just get some tools, 3/8ths socket set, set of screw drivers + spanners tourqs sockets........
take the bonnet off and start taking it to bits!

sure a zoner near you will be willing to come and help you??????????????

[pictonroad]

It's all a bit though....

Maybe I'll take the head off and get the garage to put it back

How do you lock the engine to stop the timing going out?

[Ziggy]

No need for any torx stuff on an m30...

& no need to lock anything - just leave it at tdc & cable tie the pulley to the timing chain while the head's off.

[pictonroad]

tdc, that's obvious when you get the covers off? There's an arrow?

Does it mean top dead centre, that's a guess by the way! lol

I'll get a torque wrench from Halfords tonight then and do my best, I can feel a bit of a cold coming on, far too ill to go to work.....

On that guide you leave the chain on the block and th pulley comes off with the head?

Do you mean the timing chain on the block?

[Ziggy]

Yup top dead centre is marked on the crank pulley (there's a pic in that guide), & the cam pulley has a locating pin so it can only go on in one place. Just make sure that it stays in place on the chain, & there's no need to set anything up again. The cam pulley stays with the bottom end, cable tied to the chain. It's all in the guide, just take your time...

I removed the exhaust manifolds rather than unbolting the downpipe, & took the inlet mani off first too - a bit more time (like it says in the guide!) but easier imo. Only other change that I can think of was to turn the engine by pushing the car (in gear, plugs out) - I couldn't find the right sized socket to get on the crank nut!

[Ziggy]

& halfrauds may well not be the cheapest place for the torque wrench - most auto parts places will sell them cheaper if you can't borrow one...

[pictonroad]

Is it likely that the head itself is scrap the garage had a 535 in there with a cracked head and he said BMW straight six are notorious for it?

[Ziggy]

It's certainly possible. I'd say less common than on the M20 (particularly B25), but the only way you're going to find out for sure is to pull the head off... No need to buy the gasket until you know though!

[pictonroad]

Right then...

Will get the head off at some point this week.