Ok, pulled the head, here's the diagnosis. (long)

[insanewayne]

Here's the story

Driving down the road, had been driving for 25 mins headin to my g/f's an hour away.
All of a sudden my car starts shaking, alot. I had just replaced my passenger side axle that day, replaced the boot, cleaned, and repacked the driver's side CV joint the day before that, so I thought something ####ed up. First thing I do is glance at my oil pressure, It's in the middle of the LOW section on the gauge. So I pull over. Right before I turned the car off I noticed the idle was real real lumpy...like a V8 and rough.

So I walk half an hour each way to get oil, dump in 3 litres, let it drip down (I was thinking definate bearing damage at the time) and fire her up. Nothing changed. Shit. So I do the plug test, # 2 cylinder isn't firing. Shit. So I try to start driving her back home, now i don't know quite how to explain this, but i'll try. Under "load" the car shook violently. So like unless I slipped the clutch out like hell in first the engine ran like ass and shook and just horrilbe.

Once I got going, if i gave the car anything more then 10% throttle, it did the shaking, Uphill it was ever worse. I know I shouldn't have driven it home, but I couldn't afford the tow bill, and didn't have much of a choice. And in between 2500-3000 rpm it ran pretty good .

Compression test showed 0 compression in the #2 cylinder. Stayed the same on the wet test.
So I pull the head a week later. (today)

While pulling the head, I'm telling my buddy helpin me out how it's common for service repairmen to change t-belts without changing the BS belt and how stupid that is cuz they can break, get tangled in the T-belt, and bend your valves. So you should always do them at the same time. Mine was done 20,000km's before I bought the car.(foreshadowning )

After struggling with the lower timing belt cover for an hour (one of the bolts wouldn't come all the way out, so I finally just tore the damn cover off ) I remove the T-belt, And then have a look around at the one bolt that wouldn't come out, AND WHAT DO I FIND, yeh, Broken Balance Shaft Belt hanging there. I'll post a pic of it in the next few days, But one side of it was compacted and squished together...like bent but where it bent it was like squished and shit (in two spots) , so it got jammed in something.

Anyways, Get the head off and find a hole in an exhaust valve. so thats that.

Here's my questions. Yes I searched, but coulnd't find anything relative to my situation.

What caused this horrible shaking and loss of torque. Could my blance shaft belt have jammed and caused the timing belt to skip a tooth, And the timing being off is causing this shaking combined with the running on 3 cylinders of course .

Is it possible that I could have been driving around on 3 cylinders for awhile and not known it? Or is this something I would have definately noticed. The car has pulled pretty good since I've had it.

The car ran low on oil for a lil while...Is it possible that I could have bottom end damage....And that's why the engine shakes and shit, or is it more likely that the broken BS belt/valve/timing and the bottom ends fine?

On a slightly different subject...when I was undoing the head studs, I asked my teacher, wtf are these round headed studs, he goes " Oh there torqx (sp) , go grab one". So i grab one, and it fit pretty snug, crank on her, and she slips (oviously) so i'm like #### this and look in up on here to find it's a 10 mm allan. So I goto put it back in the first head stud to be removed in the sequence, and it wont fit. I goto my teach and say, it's not a torqx, and the studs ####ed now. He looks at it, tests the allan socket on the middle stud, and it fits.
Them I'm like " Don't undo that one you have to undo it in sequence" as I hold the sheet in his face, and he goes that's for installation, and starts crankin it off, I said No it's not it's for removal. By this time he's onto the one above it. He stops, Im like, sweet so my heads going to be warped now. He's like yeh well it will have to be resurfaced anyways, just go back to the normal sequence, so I start at the edges and work my way into the middle ones that are already undone. He told me that alluminum heads always have to be resurfaced when then get removed and put back on. I could see that,but will resurfacing cut it here, or is it going to be warped to hell and have to get shaved. What will be the result of his actions and not listening to me. I'm thinkin of asking him to pay for the machining on the heads surface....

Anyways, if anyone has any insight to what happened to my baby, lemme know, and I apologize for the extremely long post, if you got this far, thanks.

Thanks

Wayne

 

[huafist]

The hole in the exhaust valve is what caused your car to run like ass. Doubt it's timing though - if your timing skips it'll bend/break valves - holes in valves come from detonation and hot spots. Show us pics.

 

[nuggets]

Whatever you do.... Before you put that car back together, REMOVE THOSE GD BALANCE SHAFTS and follow the vfaq WORD FOR WORD and your car should never shake again

i guess it's different for every car but mine runs swell

 

[insanewayne]

Yes, I was thinking that, but I would have to pull the hole engine to do that, right? Or just the plate?

Thanks for the info, also does anyone know about my head being warped?

Thanks alot for reading the novel.

Wayne

 

[huafist]

The only ways to make sure the head's not warped is to either
A: check it yourself with a metal straightedge and a feeler guage,
B: Take it to your local machine shop and have them check it.

It's possible it's not warped, depends on how long it sat with the bolts torque'd out of sequence.

 

[insanewayne]

Ok thanks, it was a matter of a minute to get them all out, so I'll get the machine shop to check it out.

Thanks

Wayne

 

[Krac_Hed]

That horrible shaking you described is exactly how it feels to drive a dsm with its balance shaft out of alignment. If you don't do the bs removal, make sure the bs is properly aligned when u put the belt on.

 

[insanewayne]

Hmm....
Ok, so is it the BS belt or the one cylinder not running that caused this, cuz if it's the shaft then I'll assume that I've been running on 3 cylinders for along time.....I'll post a pic of the valve soon, my friend just has to upload it.

Thanks

Wayne

 

[gnes100]

It sounds to me like it was the balance shaft belt breaking that caused your motor to shake like it did. It probably had a bad exhaust valve the whole time and you just didnt notice it.
As for taking out the bolts from the head. you should be fine. Its more important to install the bolts in sequence than it is to take them out in sequence, whenever you have the head off you should have it surfaced anyway

 

[insanewayne]

Ok thanks,

The hole in the valve caused that cylinder to have 0 compression, so it's possible that my car could still pull nice and beat my friends heavily modded rabbit gti that he auto X's all the time n etc...with 3 cylinders?

Thanks

Wayne

I'm still awaiting my friend to upload the pics, will do so asap.

 

[insanewayne]

Ok, If the valve had just recently burnt through, then would the inner edges be a shinier metal, like would I be able to tell that it was fresh, cuz the edges look pretty old to me, but you cant see that too well in the pic.

Secondly, there's my mangeled belt, wich oviously got jammed in some sort of moving device...I just want to know what caused my engine to run like ass, the belt or the valve - because I thought if that belt broke then the shaft just sits there right...so the other shaft would be running still.....could that other shaft still running throw things out of wack enough to make my car shake the way I described.

Thanks

Wayne

 

[2gForMe]

Teacher is partly right...aluminum heads almost always get warped....if you get a vlavejob done, they usually do the shavign for free or like 20 bucks....at least around here its free.

 

[blue92laser]

While you were probably wide open throttle, you detonated in that cylinder and caused that to happen to the valve. As detonation occurred, it made an unhealthy jolt in the motor, with the BS only controlled by the belt, when the crank took the skip...the BS wanted to keep on rolling at high RPM's it snapped that mother ####er right in half. The BS belt got tangled up behind the timing belt, made it probably skip 1 or 2 teeth, but not enough to bend all the valves. The horrible shaking you felt was the car unbalanced firing on 3 cylinders and not 4...a vibration you might of felt was due to the balance shaft not spinning in sync.

That head altogether looks fairly unhealthy from what I am seeing. Do you have enormous ammounts og blow by, post pics of the top of your block...I'd like to look at the top of your pistons.

 

[insanewayne]

Ok, I'll snap a pic tomorrow, I'm not sure, but I have wierd feeling that the valve has been like that for a long time, a month ago I did a quick compression check with my friend. Now I can't remember If I forgot to press the release valve, or what happened, but that cylinder read 180 psi, then we re-did it, and it said 0, I was confused and we had to go so I just ended it there. So I'm guessing I didn't press the release valve and yeh. .

So Is it possible to run on 3 cylinders, but still pull pretty good, I didn't have alot of power past 4500 Rpm, and now I think I know why.

I do have either exessive blow by, or leaky injectors, but I'm not sure from what, guesse I'll have to do a Compression check once I get her back together . I know I do because I can smell gas in the oil. But, I'm not shitting you guys, the car pull pretty good if it only had 3 cylinders...So I don't think my rings are going, at least I hope not.

Thanks

Wayne

 

[jdurston]

I'd be worried what the hard steel valve shard was doing to my piston and cylinder walls at 7000rpm before it made its exit from the cylinder and then what it did to the turbine blade in the turbo spinning at 100k plus rpm.

It doesn't take a lot of metal to a great deal of damage.


Josh

 

[insanewayne]

Yeh, I checked for all that, The cylinder wall is fine, the exhaust turbine, I don't know but the turbo still spooled and pulled great so I'm guessing it's good to go.

Wayne

 

[blue92laser]

That little hunk of metal probably didnt break off it most likely cracked into a few hundred peices and pretty much dissapeared before it hit anything that it could cause damage too. I would be worried about a cracked head, from any valves bending. I dunno, the only thing to do now is to take the head to amachine shop. Have them pressure check it, clean it up and check for bad news. Keep us informed. I would like to knwo what the diagnosis of the head is, it looks pretty "sick" to me.

 

[insanewayne]

Ok, we started to hit a couple valves with the grinder, my teacher was showing me how the machine works, and it was bent. ................. So we tested the valve in a drill press to check em out, It appears the exhaust valve are all fine, the intakes are a lil "ify". We can't quite be sure till tomorrow when we toss em on a lathe or the grinder. Is there a chance I could have just bent intake valves to 2 of the cylinders. My guesse is no, and they're all bent, but I guesse we'll find out.

I'll keep updating whenever I find out new news. Thanks for the support.

This is dissapointing cause the way it was looking is that all I'd need is the one valve...and some stem seals....but now it's looking worse.

Wayne

 

[insanewayne]

Just checked....all the intakes are bent.....

...............

Arghhh ...

Wayne

I'll post a pic of the cylinders later on tonight.

Wayne

 

[trbotaln]

a valve cools when it sits on its seat and then the heat is tranfered through the head to the water jacket. It looks like you had a lot of carbon build up in the head and that is what keeps valves from seating. when they don't seat properly = burnt valve. Also when you straighten a bent aluminum cyclinder head they bolt it down and cook it in an oven until it is straight. This procedure must be done prior to decking the head to keep the cam bores in line.

 

[insanewayne]

That's some intersting info to know, about the head baking, thanks.

I've thought about it, and I need a vehicle and want to start on my AWD or my 4g63 colt "ghetto sleeper", so I've decided to fix her, find a source of income with her, fix her some more, then sell her.

I'll let ya'll know how the lil project goes down.

Wayne