E32 730i 1986 Overheated desperate help/advice needed
 

Hi, new here so please bear with me and have limited technical knowledge.
I am also thinking my first visit shall be short lived due to the nature of the following occurences.
I recently acquired an E32 1986 730i and hadn't been used in a while (6 months) but to my knowledge it had no known faults. Started her up just yesterday and after running smoothly for around an hour, just sat on my drive, it seriously overheated, the full works - steam and water coming from under the bonnet and a loud bang, which occured after running to its aid and switching her off, bang believed to be a burst pipe on inspection afterwards, half the pipe had been cleanly blown away - this water pipe is located at the top of the engine head where the water pump is located, not sure where the other end goes without further inspection.
Happy to add a photo of this for anyones interest, if that is possible.
The car although overheated, needle was right up as far as it would go!, was still running smoothly from what I could tell during my panic and frustration at my partner just sitting there watching it happen!!! Well, she was in the vacinity at the time so for all sense and purposes I blame her, Blonde of course! Sorry to any intelligent blondes reading this but there are those that aren't.
So, my question here is what should I do first without getting into any expensive repairs, garage repair costs out of the question, re-building with my limited technical knowledge impossible. Suggestions please I'm desperate to get this baby on the road, if at all possible.
Would replacing the burst pipe and re-filling with water/anti-freeze be the first repair to then establish if it will start or is this likely to just cause more damage, if not already? Would it be safe just to start her dry just to see if it starts?
I am expecting the worst already so please don't be shy to tell me the worst case scenario.

Send a picture if you can, it might give further hint as to what the problem is. Broken radiator connection? Fan belt? Water pump? I'm just guessing. You may have escaped serious damage, however. If your luck has held, my guess is that you might be able to get by with replacement of whatever hoses let go, or belts, or the radiator, or whatever, plus a complete flushing of the coolant system, radiator AND engine block. Sitting for six months invites the accumulation of deposits, and I can only assume that time period just adds to whenever the last time the system had been flushed.

added photos
 

Thankyou for your reply and assistance, very much appreciated.
Not sure exactly what to take pictures of other than the burst pipe, everything else appears to be intact. Possibly coolant leak from around the thermostat housing pipe, bottom connecting pipe, but not sure if that was before or after overheating.
The fan spins by hand, not sure if it is supposed to, I can't see anything turning inside the housing on the other end of the fan where the pipe has burst off, but would I be able to see anything spinning.
I have taken pictures but unfortunately they are to large in size to upload, it will not allow me to do it! Sorry, I shall keep looking for a way to do it though.

I know what you mean about uploading pics, it can be frustrating. Obviously you have some plumbing repairs to do, it's conceivable that the burst hose could have let go due to age (which means others will have to be changed as well), but my guess is that a connection has failed, possibly the bottom one you mentioned. As to the fan spinning freely, I think it should do so, with very slight resistance; if it's freewheeling, I think that would mean the water pump is shot.

I wish I could be more definitive, again my guess is that you're in for radiator, thermostat, and hose replacment, and complete flush of the cooling system (kinda goes without saying). If you shop around, my guess (and it's largely a guess) is that you're in for $300-$500 in parts, maybe nearly double that if you have to throw in labor. If you caught the overheating quickly enough, there may be no harm done to the engine, but short of more dismantling of the engine, I think you just have to wait and see what happens once you put things back together and start driving around.

Hi 3050RPM, I presume you are in the states from your estimate quoted in dollars$$$$, nice to hear from someone across the atlantic.
Hose ordered today so should be with me tomorrow afternoon, £10 so not too expensive at this point, will consider replacing other hoses after trying the car with new hose fitted. On inspection of the burst pipe I personally wouldn't say it is aged, no obvious signs of wear, doesn't look cracked or brittle.
Although I said the fan spins there may be resistance so not so sure it is freewheeling, I guess this would become evident when the car is started again, if it starts, and if the fan spins whilst car running then I assume the water pump is OK.
I shall remove the thermostat and test this too, over pan of boiling hot water.
How do I flush the cooling system, is it done and one complete system or are separate parts flushed seaprately? Hose pipe down the radiator or coolant top-up tank? Guidance here greatly appreciated!
Thanks again for your advice.

Well, we're still using $$ for the time being, I imagine some time soon we'll have to make the change over to the Euro or the yuan...

Anyway, before that happens, if the hose looks okay, then I'd suspect a broken or cracked connection, perhaps even in the radiator itself. But these are just conjectures, so certainly do that close inspection under the hood (bonnet?). I'm not sure that an automotive thermostat can be adequately tested using boiling tap water, don't forget that one purpose of coolant is to allow for an increase in boiling temperature. In any event, if you've gone to the trouble of removing it, you may as well just replace it with a new one.

Flushing a cooling system means draining the fluid from the radiator (usually a petcock at the bottom of the radiator) as well as opening up the drain plug on the engine block. I don't know where this is located on your engine, so a little research is in order (and it can be a pain to get to, and to undo). Procedures can vary a bit, in some cases putting in a mixture of demineralizer with distilled water is a good idea to provide a second flush. I think BMW advises using solutions that have no phosphates, borates, or silicates in them (or some such compounds), but I think the modern, reputable products on the market all avoid them. The 50/50 premix products are very convenient to use, just use directly, no need to do the mixing yourself. Obviously you can go to a BMW dealer and get their product, but at two to three times the cost of major comparable brands you can get elsewhere.

Do some online searching and you should come up with procedures and helpful hints to make the job go smoothly, withou spilling too much of the stuff around.

Progress so far
 

Hi, weather hasn't been so good here for the past few days, cold, wet and windy, certainly not preferred conditions for working on your car. But did get a dry spell when I was able to fit the pipe that eventually arrived, refilled with coolant, car started but the computer warning message came up 'Engine oil pressure low'. Not sure I have had this before, left the car running for a couple of minutes and sounded OK to an untrained ear then switched off before causing any further damage. Things are looking more positive but I'm not holding my breath just yet!
Anything I can check or do to resolve this, what are the most likely causes?
No other warning lamps or messages were showing at this point i.e. low oil light not illuminated.
Thanks

Well, the obvious question is, have you checked the oil level? It's not a good idea to let an engine run when such messages appear, but te warning message could be an anomaly, arising from a sensor getting dire messages when the overheating occurred, but I wouldn't place too much of a bet on that. Did the message disappear while you left the engine running?

As a simple, practical matter, before any more elaborate diagnostics, I suggest changing the oil and filter as part of the repair routine here. After that, running the car for a bit and then visually examining the clean oil might give you some indication whether you have cylinder head damage.

I'm sure I had checked the oil level but will check again, yes the warning message only appeared briefly with a warning audible 'Ding'.
Shall do the other as suggested, cheers.

OK, brief is good, it could be just a fleeting signal upon start up after all that had happened previously.