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Discussion Starter #1 (Edited)
I have not driven my car much, it's 113,000km right now and it's a Alpina B8 from 1995.

Last weekend i took it for a run and noticed a knocking noise from the engine bay on the way home, i have tried to diagnose it and beleive it comes from the back of the engine and downwards but not totally sure, it doesn't seem to come from the chain guides.

I checked all spark plugs to see if they were all fastened correctly but no fault found there, it gets worse when accelerating as i can hear the knocking noise much more, it was difficult to snap up the noise correctly but you can hear something is knocking or is loose.

I've uploaded a video to check if someone could guess what is going on, i know the previous owner checked the bolts for the oil pump and it was ok.

The only real guess i have left would the the flywheel or some rod bearing, i changed oil before this to Castrol Edge Titanium 10w/60 and there is oil on the stick.

I have a BMW expert coming over this weekend but i want to check with you guys also, i know some B8 owners have changed flywheels so maybe you recognize the sound.

https://www.youtube.com/watch?v=FbXmA6MfyaU
 

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Ooooo not good! A stethoscope around the area at idle should give a better indication. Don't think, from the sound recorded, I'd be driving anywhere.
 

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Discussion Starter #4
A BMW mechanic has been looking at it today...

Seems to be head gasket, doing a compression test next week to be 100% sure, the compression seems to go into the other cylinder which makes the engine run not so good, first we thought it might be the intake gasket, but we have to wait and see what the compression test says first.

Anyway, it really surprised me with no prior warnings, just happened.

Pretty much disappointed right now.
 

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I wouldn't expect a gasket to knock like that so will be interesting to locate the problem. I'm glad you say it's off to a mech…and you're not trying to fix it yourself. If HE makes a mistake He must rectify it! A leaking gasket, if it makes a noise at all, if often a rough engine and/or a short hissing sound as air escapes the cylinder (if it escapes externally). Usually when an engine 'lets go' it will happen quickly and with little or no warning, the dash will have red lights flashing furiously…time to shut down quickly to minimise damage. Whatever the problem you are lucky enough to have heard the noise early…IF it's more than a gasket it could still be a costly rebuild. Can't make shortcuts there. Unfortunately. Even the best built engine can sometimes have a major internal consequence. Let's hope you don't have anything like that.

I once had my M535i run out of oil. After a routine service the mechs forgot to replace a secondary plug into the sump. The car ran perfectly for 30 miles until the gunk tightly packed in this second hole finally blew out and oil just all dumped on the road very quickly. As soon as the dash lit up I switched off and coasted to a stop. The mech admitted his men made a mistake and completely rebuilt the engine. There was no damage caused at all…but at my insistence they rebuilt it. Just refilling with oil when there is no way of telling what damage MAY be caused was not an option. in another car…I had a valve spring brake at 140mph, the engine completely self-destructed in one second and left a fist size hole in the block.

So, no water in the oil? No short hissing sound of air escaping outside the engine? No water/oil escaping around the head gasket. Good luck, keep us up to date.
 

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If it's as bad as I think it might be - on a positive note - it's the perfect time for steel sleeving, forged rods and pistons with a supercharger on top.
 

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Discussion Starter #7
Yes the valve gaskets were leaking as well so that needs to be done, the car is being picked up tomorrow so they should make the comp test shortly.

It's one of the top BMW mech in my country so he knows his stuff, he told me not to drive it so it's being towed to the garage.
 

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That sounds a bit like the noise I had when my Head Gasket went. My wife was driving home and it suddenly started to
sound like a tractor and run intermittently only on 7 cylinders. Could be that if you still have the original 'card' type
HG as opposed to the later uprated 'metal' type version from M5.

Lucky you caught it early anyway, good luck.
 

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Discussion Starter #10 (Edited)
That sounds a bit like the noise I had when my Head Gasket went. My wife was driving home and it suddenly started to
sound like a tractor and run intermittently only on 7 cylinders. Could be that if you still have the original 'card' type
HG as opposed to the later uprated 'metal' type version from M5.

Lucky you caught it early anyway, good luck.
Thanks, yes it suddenly started and exactly like you say, sorry to say I am on the original organic HG.

I noticed the temperature needle was slightly above the middle marker when it happened, usually it is slightly below it, I am very picky with my cars and notice changes early and take care of them before they get worse.

The old saying that you shouldn't worry about the HG as it's a low mileage car and so on, i guess it has nothing to do with that, it can happen just suddenly without notice.

This was one of the things that hesitated me from buying a B8 with original HG and now it has happened, should have stayed away buying the car after all....it's a ticking bomb
 

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It can happen, well it almost certainly will eventually. Some cars last a lot longer than others, my feeling is it depends how they were previously
driven. I've heard of cars with only around 50-60,000 and it lets go, others last bit longer.

When I bought my B8 it had around 200,000 on clock with the organic HG but it was running very well so I left it alone.
I felt why touch it if it's good. However, I never really pushed it as I did have that niggling doubt in my mind 'what if it goes'.
When it eventually went it was at 251,000. Luckily it was my wife driving it slowly home, could have been a lot worse at higher speed.

In the end I was lucky and it did minimal damage, you can see it here in my thread on the engine rebuild
http://www.m5board.com/vbulletin/alpinaboard-com-bmw-alpina-discussion/191645-b8-engine-rebuild-mini-restoration.html

http://s951.photobucket.com/user/chrislux/library/Alpina B8 CT1963/Engine rebuild and restoration?sort=6&page=1



Good luck, hope your's is not too expensive to rectify
 

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In the past it was said, that the original gasket would last 150 000 km - but I guess 19 years isn't making it last that long. I had my changed at 140 000 km before it went - now at 210 000 km no problem. The B8 is not really a ticking time bomb - in particular the gasket is a known problem and once changed, you have nothing to worry about.

Cheers, Alex
 
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Discussion Starter #13
Compression test done, low comp on 3 and 4th cylinder and 7 and 8th cylinder.

I am taking the car to a Alpina specialist who will change the headgasket
 

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Jarls Bilservice in Helsingborg can probably handle this unless the damage to the engine block is very severe. They did an excellent job on my B10 V8 when the head gasket on that one gave up on existence. Not particularly cheap, but probably cheaper (and easier) than to find a new engine.
 

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Discussion Starter #18 (Edited)
They called me and will start working asap.

Jarls doesn't need to lift out the motor, they change the gasket in place, they seem to really know their stuff.
 

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Discussion Starter #19
Jarls Bilservice in Helsingborg can probably handle this unless the damage to the engine block is very severe. They did an excellent job on my B10 V8 when the head gasket on that one gave up on existence. Not particularly cheap, but probably cheaper (and easier) than to find a new engine.
What were your symptoms when the gasket failed? any noise?
 

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"Lanab" my friend… Suddenly you have a serious engine knock…THINK THE WORST mate…there's little choice. You've a problem…happens even to us diligent 'experts'. You've a choice to SELL IMMEDIATELY "as is" and get nothing, or have it rebuilt to top specs. Then you've paid for a new donk and drive it like you 'own it' and enjoy the well spent money. Is there ANY warranty from previous dealer/owner? At the end of the day you have a 2nd hand machine according to price and associated guarantees. Tough choice…YEP!

People break, but can be fixed
Machines are made by humans…so they break…
But can be fixed

My advice; As you cry blood, fix it and then enjoy anew UNDER FULL WARRANTY!!!
 
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