My 318i just died...Hole in my piston? What caused this?Pics

[EOS]

Was just driving along doing 70mph, suddenly hear a Poom kinda noise followed by complete loss of power, and exhaust making funny noises like the car was really over fueling.

Pulled over straight away, had alook under the bonnet/underneath etc all looks well, no fluid lost etc. Go to start it and the starter just spins really quick. Like it wasn't engaging. Only it was cause after a while the car caught and fired on one cyclinder and died straight away. The guy that picked the car up for me to get it home said it only sounds like its got compression on one cyclinder.

So far today (inbetween the snow) I've taken the viscous fan off etc and the timing covers.

Belts still on there and under tension, nothing seems to be out of place.

But how can I check to see if its jumped a tooth etc? There doesn't seem to be anything to align it?

Also am i right in guessing when both inlet and outlet valves are closed and the piston is TDC is this TDC on the compression stroke?

Im gussing my number 1 was at TDC by putting a bit of tube in the spark plug hole and winding the crank round till the tube didn't go up or down anymore.

It was also very easy to turn the crank with a spanner felt like there was almost no resistance.

It hasn't lost any fluid. oil or water.

Im a bit lost on this one, and kinda need to get it on the road again by tuesday as its meant to be the reliable daily driver lol. So far turning out to be a right pain in the arse. lol

Thanks for any advise.

[E30Mark]

Does the cam actually turn when you crank the engine over by hand?

Beautiful blue sky & sun here

[EOS]

Yeah the cam goes round, all the tappets seem to be going up and down and aren't hitting anything (feels like there not)

Got the rocker cover off and all looks well under there, although im sure that won't tell me much.

[uzdubmwe30]

have you tried bump starting it too see how much compression it has, or done a compression check on it? if the belts slipped and its touched valves they'll be sticking open just a fraction which would cause it to be really low on compression and turn over really easily, what condition are the spark plugs black, brown, covered in fuel?

[EOS]

Black and covered in fuel. One took number one out. Started snowing again.

I tried bumping it but no effect.

I can't get hold of a compression tester at the moment. But im sure its going to show that i have not alot.

So if the belts slipped its pretty much garunteed the valves have hit the piston and bent?

[uzdubmwe30]

are you still getting a spark from the leads? did it feel as though it had compression when you tried to bump it?

If the belt has slipped lets just say that the valves will be tweaked and are not going fully upto their seats which would cause the low compression.

Take all the plugs out if you haven't to check condition, check for a spark and see if the timing is still good (set no.1 to tdc then time up the top cam, there should be a mark on the sprocket somewhere that relates to the timing casing)

[EOS]

I'll have to check the spark tomorrow but i faily sure it was.

When i tried to bump it it had resistance as i pulled the clutch up. But couldn't tell if it had compression.

When you try and start it normal the starter sounds superquick like theres no resistance, would that indicate no compression?

Yeah I wasn't 100% sure on what needed to be lined up.

I think i have number 1 at TDC both inlet and exhaust valve are closed and the piston is at the top of its stroke. Is this the compression stroke? If it was the other way round wouldn't that mean it would put the timing 180 degrees out?

[uzdubmwe30]

As much resistance as if you were bumping a car under normal circumstances, The starter spinning round really quickly may just be the solenoid inside it not kicking out the ring gear to engage onto the flwheel, sounds stupid but that may be it,

If theres no compression the incoming air/fuel mix will just be able to pass through the cyliders and straight back out of the exhaust system if the valves are tweaked,

The firing order is 1 3 4 2 so take out all the plugs get no 1 up to the top, remove whatever your using to indicate this (long screwdriver is best) and place it in 3 and continue turning, if it is about half way through the stroke when you start turning the crank over from no 1 tdc then you've got it right.

Hopefully that makes sense

[EOS]

yeah i'll have ago at that tomorrow lol.

The starter defo engages and spins really fast as the car did catch and try and start on one cycliner.

Starters been fine unsually as well.

Reckon the valves could be dead then, cause when it went pop that exhaust made that kinda noise like the car was really over fueling.

[uzdubmwe30]

c'est possible then,

If you can find me a late m42 timing casing then I have a 1.6 m40 thats covered 98,000 sitting in my car at the moment that you could have for a few notes. lol

good luck anyway mate,

let me know how it goes,

matt

[insertnamehere]

Crikey, does sound like the belt may have jumped a tooth. If this is the case though, isn't it possible that the valves are not bent & you're just losing compression due to incorrect timing?

Either way I think the course of action is to check the timing & correct if necessary, check comp. then & if you're lucky it'll be back & you can get away with just fitting a cambelt kit (if it's jumped due to a fault, maybe it just wasn't tensioned right in the first place...)

Hope you get it sorted, Dan.

[EOS]

If this is the case though, isn't it possible that the valves are not bent & you're just losing compression due to incorrect timing?

Thats what I was hoping lol.

Weather looks better out there today so will have another play. Don't I need the BMW setting tool to do the timing properly though?

[EOS]

Right got some pics now.

Managed to put a bar through the gearbox bit into the flywheel to see if its TDC.

Heres the crank pully thing, its got some timing marks that im guessing whoever fitted the timing belt last time made.

At TDC the timing marks are only just out? Looking at the grooves not the big blob of tipex on the smooth part. Can't see it well in the pics but the grove has a small amount of tipex on it as well.



And now the cam timing marks at the same positon, just out. Im guessing they used the bumps in the covers to align to.



Should the belt have this much slack? Can easily pull it away from the roller?



Now aligning the crank perfectly with the old timing marks,



The cam sproket previous marks seem to be a tooth out?
Does this suggest its jumped a tooth, and thats why the car died?



If it has only jumped one tooth, would the valves have hit the pistons or buy luck it could be ok? And just a case of resetting the timing?

Thanks for the help so far.

Regards

Matt[/img]

[EOS]

Well changed the timing and put it all together, and still no good.

Will do a compression test next.

What should the cylinder compression be roughly?

[uzdubmwe30]

around the 180 - 200 mark i think, if it's only a tooth out then it shouldnt have bent valves, but do the compression test before you start playing about with the timing as if you adjust it one tooth when its not needed you could bugger things up further. make sure its definately that problem before attempting to do anything.

[EOS]

Right just done a compression test, had nothing on 1 and 3 and around 11 bar on 2 and 4.

Check the spark plug from number 3? What could have caused this? And all the other problems?

Thanks guys.

[uzdubmwe30]

looks like it's dropped the inlet and exhaust valves right onto the nose of that poor plug, its possibly dropped a valve, a valves broke off the seat or the belts slipped alot! Either way if what i'm seeing on my screen is a spark plug that looks like its been hit with a hammer it'll be a new head minimum,

Bad luck mate,

matt

[EOS]

IF it dropped a valve, how comes i have no compression on 1 as well?

That dead plug was from 3?

Well i got a engine off a mate for £70 to stick in as a replacement, gets me out a tight spot for now.

Just wondering what the cause of this was. The timing didn't look that far out from all the above checks. Would be pretty random if the belt slipped and landed back in perfect timing?

[EOS]

Any ideas?

[EOS]

Engine was well looked after, only 120k got all the MOT's from new to back that up, and had full BMW service history until early last year?

[insertnamehere]

Oh bugger, I think is the phrase I'm looking for. That belt did look a bit loose TBH, at least you've got a spare motor to drop in it for the moment, but please do whip the head off the old one & post pictures as I for one want to know what the hell happened here!!!

I suppose it's possible that the cam timing has slipped all the way round or maybe 180deg. or similar & that bottom pulley deffo looked a tooth out also but either way, sorry to hear (see? ) what's happened & hope you can get it sorted soon.

[EOS]

Thanks, shame weathers broadcase rain all week and weekend as i really want to get in there and take it apart lol.

Took the top half of the inlet manifold off this evening (then gave up cause of 5hitty weather) and there was metal chunks rattling about in the top part of the manifold, and loads of metal shards down the inlets going to 1 and 3.

Hopefully tomorrow I might have the head off. Will be posting pics as i go lol.

[uzdubmwe30]

Thanks, shame weathers broadcase rain all week and weekend as i really want to get in there and take it apart lol.

Took the top half of the inlet manifold off this evening (then gave up cause of 5hitty weather) and there was metal chunks rattling about in the top part of the manifold, and loads of metal shards down the inlets going to 1 and 3.

Hopefully tomorrow I might have the head off. Will be posting pics as i go lol.

Now that sounds like the little ends have gave up and punched a piston up into the valves, you'll probably find a shattered piston lurking around in one of the bores.

So what speed did you say you were doing again? and in what gear? Wasn't a misshift that shouldve gone into 4th and it went into 2nd was it? lol,

Sounds abit suspect to me,

[EOS]

So what speed did you say you were doing again? and in what gear? Wasn't a misshift that shouldve gone into 4th and it went into 2nd was it? lol,

Was doing a constant speed of 70mph and it just mad a poom noise and let go. I was on the way back from having my sleeve done on my arm so defintely wasn't putting my toe down. Thats whats surprised me so much.

The cars only got 120k on the clock and all the service history and everything to back this, up, engine was alittle tappey at the top but i've had 318's that have been a million times worst.

There was no knocking ior strange noises at all. And wasn't using any oil or water.

If i was driving like a tit and it let go that would be fair enough, but to go how it did really surprised me. (Which i dont do anymore cause i've just brough my first house with the girlf and am mega skint.) So looking at the mpg gauge more than anything else lol.

[uzdubmwe30]

I was just comparing it to a mate of mines 1.7 puma he did a miss shift from 5th to 2nd when he shouldve hit 4th and annhialated his bottom end and bent every valve, dont ask me how he managed it, probably racing the daft c@nt.

what oil grades been in it while you've owned it and how much of the 120,000 have been yours?

[EOS]

I've only had the car around a month, but the last stamped service was in december and that was a BMW one. So guess it had the right stuff in it?

Im not having much luck with cars at the moment, had a nice slammed mk2 golf not so long ago until a van drove into the side of it and wrote it off then drove off. So managed to break that to help fund the E30, thats now just eaten its engine lol.

Which is also a right c0ck cause the heating in the house packed up in november and we've been saving up to get that fixed now looks like im going to have to dip into that to fix the car lol.

And with the weather we've been having, its one bloody cold house at the moment lol

[uzdubmwe30]

So it's been regularly serviced by beemer or just a few, then again sytner and the other big bmw places only let their young gonks work on the older stuff as their less expensive to replace if they f*ck em up, You made the right move from the dub scene to the e30 louts far better crowd and help when stuff goes wrong.

Some on here will slate you for having an m40 under your engine bay but they do take a fair bit of shit if looked after, mines been cooked on low bake twice (knackered fan coupling) and it still has a fair bit of go and has never skipped a beat once.

You'll get by bud, Shit just comes all at once then goes for a while normally, What you could do is by the missus a trench coat then she might keep quiet about the bm for a while or paint one room in the house that normally distracts them for a while, lol. Summers on its way pretty soon anyway,

If I was a bit closer I wouldve gave you a hand with the swap,

Let us know how it goes.

matt

[EOS]

Some on here will slate you for having an m40 under your engine bay but they do take a fair bit of shit if looked after, mines been cooked on low bake twice (knackered fan coupling) and it still has a fair bit of go and has never skipped a beat once.

Lol the M40 is the daily i got a beast in the garage thats still miles off completion due to the house etc,

M50 turbo, will try find the thread

[EOS]

Heres the thread.

Really need to sort the daily out, and the heating and get back on this lol

http://www.e30zone.net/modules.php?name ... o&start=25

[uzdubmwe30]

coolio, I remember having a quick brush through that thread a while back and it inspired me to do mine, It was a toss up between m42 turbo or m50 non turbo have decided to go the m42 route tho as I picked up an engine and box for a steal, all I need is a lower timing casing then I can start rebuilding the bloody thing, Then after it's had a good rebuild go down the turbo and bike carb way but as soon as I can get insured on the damn thing with all them goodies on it. Who you using for insurance when it's done? and do e36 diffs fit straight on when the backplates swapped?

Anyway, getting that engine in the bay during a weekend i'd expect you to have that little m40 stripped totally by now so we can have a look see at whats gone on!

[EOS]

Yeah must be getting lazy these days lol.

Its cause im having to get a lift into work with a mate so not having much time in the evening to do things don't help anymore lol. In work for 7 and cause of the traffic etc dont seem to be getting home till 6:30 7ish. Still all about this weekend. Hopefully the rains not to bad, and I can get hold of my mate about that engine, he's all of a sudden gone very quite and hard to get hold of which is a right pain.

Im not sure about the E36 diff thing, when i've looked at them always thought there was no chance of them going on. However i did here that a E28 diff with a back plate change will go onto an e30. I've yet to get one to check out.

I got some diff internals from the states for my M50 one, so thats a 2.93 ratio. Not sure what they was from, but should give it a much nicer cruising speed lol.

[insertnamehere]

Said it once on this thread & will say it again... CRIKEY!!! Metal shards in the inlet ain't good at all & does smack of a top end let-go, though I would have thought you'd hear it on it's way out for ages, even above the M40's tappets as you seem (from your other thread also) to be fairly "in-tune" with your motors! Definitely need to see what's happened & believe you me this thread has probably advanced my own cambelt change plans by about ohhh, a year or so!

[gra325i]

Definitely need to see what's happened & believe you me this thread has probably advanced my own cambelt change plans by about ohhh, a year or so!

X2

[insertnamehere]

Just remember, it's all good fun till somebody loses an i....

[EOS]

Right check these pics out. God knows how it happened, especially at the speed i was going at, and at the time was a very constant speed i.e wasn't accelerating - decelerating.

Piston looking very dead.



Head missing one valve.



Valve



Nice big hole