blown head-gasket or blown engine?

I've got coolant coming out my exhaust...from what I've read, its alot of work to tear down the engine to the point where you can examine the head gasket to know if that is the problem. Can anyone estimate how many hours a mechanic should take to do this? And if its not the gasket, has any of the work needed to replace the entire engine then been done, so I don't have to pay twice or not? Does anyone know of a website I could go to to see what the steps involved are? many thnaks in advance....

Reply to
Freebase
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Depending on the mileage you have on your car - I would suggest getting a used motor with lower mileage - Let me know if you need help locating one.

Reply to
kentagi

oops sorry, I forgot to mention its a 1994 325is with 213,000 km on it .... it sounds like you are suggesting that its a whole lot of work to get down to the head gasket and replace it , compared to the cost of putting in a new engine? The cost of a new engine looks to me to be about $3K-5K , and it seems like the engines go for about $1,200 and they all seem to have 117,000 mi? km? ( am a little suspicious of this !) on them.... the cost of a head gasket would seem to be less than all that?

Reply to
Freebase

On 10 May 2006 09:22:13 -0700, "Freebase" waffled on about something:

You could try a compression test which requires nothing more than removing the spark plugs.

This will show if the head gasket has gone between the cylinder and water jacket.

Otherwise the next likely source would be a cracked head.

Has anything happened to the car just before this happened? i.e. Did you over heat it due to an older water leak? This can warp the head and prevent the head gasket from making a good seal.

Dodgy.

Reply to
Dodgy

Well there is some history here... two years ago , something went wrong in the cooling system when my son was driving it but he drove it for longer than he should have in that condition. I had the cooling problem fixed, and no further problems for some time, then one year ago , a repair shop tore the engine apart and told me I had a crack in the block..they sent it away to be 'welded' ..... $2600 and one year later I have coolant coming out my exhaust...the BMW dealer did a 'leakdown test' ( is that same as 'compression test' ?) and said cyl #3 had oil in it..need new engine..but I'm not burning oil..don't trust them at all..they only understand new BMW's and major replacement I think, nothing less.... ?

Reply to
Freebase

I went to a "BMW specialist" to get an estimate and they wanted $1800 to remove and replace the headgasket. I then found a mechanic, who use to own a shop that only worked on BMWs, who charged $1100 to replace my head gasket on my 90 535i, 5spd, 106K miles. The $1100 included replacing a cracked t'stat and housing too! The broken t'stat was probably the reason my car overheated.

Reply to
bfd

Do a compression and leakdown test on the engine before you spend the time and money to tear it apart.

Reply to
Fred W

Bfd's experience is what scares me about these so -called 'specialists' ,, I've already been hosed for $2600 and ain't gonna take it any more..I wish I'd known about this newsgroup a year ago...anyway... when you suggest the compression and leakdown, can either or both combined indicate with some certainty whether it's the head gasket or a cracked block?

Reply to
Freebase

I had that once with a Fiat. Sick of throwing good money after bad I bough a rusted out hulk of one with an older engine that wasn't great but wasn't bad. Swapped it in a weekend myself and drove around for qiute a while before I went away to school and my parents sold it when I wasn't looking.

Point is, even a slightly worn but working engine will end the suffering and they can be had cheap - especially if you aren't looking for an engine per se.

Reply to
Richard Sexton

Whoa, the plot do thicken don't it! I was gonna suggest a crack in the block after your first post, then you posted the rest of the story. I'd bet you a thousand bucks that the weld has failed. A new engine is the solution.

-- Cliff

Reply to
clifffreeling

Any good mechanic can tell you in less than an hour if you have a blown head gasket but he probably would need to tear it down to tell you if the head is cracked. There was a problem on the 318is in the early 90's that required replacing the head gasket and that job usually cost about $1200 but that was

10 years ago so I'm sure it's more now. If the head is cracked you can add about $1800. A rebuilt engine is probably the best course of action if you intend to keep the car for a while.

Reply to
Jack

reading this thread has freaked me out a bit... i have a '96 318is which had a full service about a months ago, had about 400 bucks work done and pretty good feedback from the mechanic about its condition.

...but a note on the invoice as something which needed attention was that the engine gasket is leaking oil inside, and this should be replaced within the next few months. i was quoted about $150 for a new

3rd party seal (does that sound about right..?), was told it would cost more for genuine bmw.

one thing i've noticed is the temp gets up to about 60% within a few mins of driving, although i'd heard 318is's ran hotter than most. i've never seen the temp go over about 60%...

Reply to
gimp

On 10 May 2006 11:09:46 -0700, "Freebase" waffled on about something:

Wooooo.... Okay... The lemon alarm has gone off... (not you, the engine!)

I'm not sure about cracking a block from an engine over heat, I haven't heard of those very often. Usually it's the head that cracks or warps (The head gets a lot hotter than the block, it's where all those lovely still expanding superheated gases whizz out of after all!).

I don't know what a leak down test is, but if you've got oil in #3 that's sounding very much like a head gasket or warped head (or the mother of all cracked heads).

Do you have any other symptoms, water in oil, oil in water, excessive pressurisation of the cooling system? I had a head gasket leak once that inflated the top hose to about 6 inches diameter! I opened the bonnet/hood and you've never seen anyone run away so fast in your life!

Dodgy.

Reply to
Dodgy

That would be a valve cover gasket, not a head gasket. Not a major deal.

Reply to
Fred W

No, they both just indicate leakage into or out of the combustion chamber. Once you know that you have to disassemble to find where the actual leakage is occurring. But if you just had the block repaired not that long ago a new head gasket should have gone on there then. Assuming they did a good job that would make the head gasket less likely.

OTOH, if they did a sloppy job or did not properly plane the mating surfaces (if they were chewed up at all) it might mean it is more likely. Always suspect the MRFWU (Most Recently F***ed With Unit)

Reply to
Fred W

Thanks for asking about other symptoms... no oil loss , no white/grey guck in the oil cap, oil on the stick looks a normal 'brownish', no expanding hoses. The 'check coolant level' does come on right away even right after I top it up ( sensor?) . Also, it seems like if I don't put the car in the garage overnight, its possible that when I turn the ignition key, I'll get a 'clunk' and no go ( has happened twice in two months) .. then a few hours later, it will start fine. I'm hearing that this may be a 'vapor lock' , where in that one cylinder there's no ignition because of leaked coolant. Does that make sense? If so, why does it startup later on? The car absolutely 'purrs' while driving, no missing etc....My question is this.. I've been driving it for about two month like this, trying to decide what to do with it.... am I making anything any worse by driving it while I scrape some cash together, if it needs a new engine anyway?

Reply to
Freebase

Regarding the $150 quote you got, my experience is that the only time you'll get anything done at a BMW dealer for $150 is if you take it in for an oil change and no filter replaced! Be very wary of the labour costs involved... that $150 part could cost $1000 to get installed because of the same kind of time I'm facing just to find out what's leaking in my engine. I'm hearing that to get down to the head gasket is several hours labour.....$$$$$ !!!

Reply to
Freebase

On 11 May 2006 05:23:32 -0700, "Freebase" waffled on about something:

Not vapour lock, hydraulic lock.

Vapour lock is petrol evaporating in fuel lines/carbs when they get too hot. You end up having to crank the engine until "real" liquid fuel comes through.

A "clunk" no go, engine can't turn, is your piston trying to compress a cylinder of coolant that's leaked into the cylinder while it's been left parked up. Liquids don't compress very well, unlike an air/fuel mix.

It clears because after the piston has manage to apply a bit of pressure to the liquid, it slowly leaks out, either the way it came (the crack in the head/block or leaking gasket), or past the valves, eventually the pressure decreases and the next time you give the car a go the piston can manage to squeeze the remaining liquid past the compression stroke, down it goes on the power stroke (although not producing any power in that cylinder) and then on the exhaust stroke it chucks the remaining fluid down the exhaust.

This will only lock a cylinder that coming round to the compression stroke.

It purrs along because the leak is slow and doesn't have a chance to leak into a cylinder whizzing up and down 50 times a second.

Dodgy.

Reply to
Dodgy

Sorry if my post alarmed you but you are safe from the defect I was referring to. It was only applicable to the M42 engines made from '90 to '92 and involved an internal gasket called the "profile gasket". Failure caused a rapid loss of coolant and often resulted in an engine overheat fatal to the cylinder head. This was caused by a design error in the material chosen for this gasket and affected more than 50% of these cars but BMW NA refused to accept responsibility forcing owners to pay for the fix.

Reply to
Jack

Freebase, Maybe we should go back to the beginning. Why do you think you have coolant coming out of your exaust. Does your car emit huge clouds of white smoke after being started in the morning? That's what would happen if you are leaking enough coolant into the engine cylinders to cause a hydraulic lock. Or do you just see water dripping out of your exaust pipe when the car is running? This is perfecly normal.

Reply to
Jack

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