Timing Belt Snapped.

[Madhatter]

Are you sure? I mean the valve stems go right down the middle of the valve guides. Couldn't I have bent a stem or two? But either way, now I'm thinking the noise is either that or the head of the valve hitting its seat wrong. Before adjusting the clearance I noticed it was less, like maybe .008 or .009. Might just have to go back and see what happens.

Positive. If you take out a valve you'll see they wear a little ring nearly an inch from the valve. The valve is curved on the back side and flares out much larger than the (slightly less) 7mm of the stem. The guide is driven hard into the head and doesn't flex/move. If you bend a valve it is because you hit a piston.

Pulled the head off today. Two exhaust valves are bent and the pistons were nicked but my uncle says they should be fine.

Comfirming that it WAS the timing belt snapping indeed as presumed. Also, there's a metal roller the that timing belt doesn't actually spin but just slides along it, like a bearing. It was pretty bent and touching the timing cover. Any know what could cause that?

The roller thing is the timing belt tensioner. When its set in place properly it keeps tension on your timing belt. If it was all sorts of bent and/or moving around, there is a good chance something failed with the tensioner. Its kind of tucked to the right of the water pump, there is no way it should touch the front timing cover if the tensioner was in place properly and in working condition. Did you find the spring and pin that sit between the water pump and the tensioner?

[tonyloban]

Pulled the head off today. Two exhaust valves are bent and the pistons were nicked but my uncle says they should be fine.

Comfirming that it WAS the timing belt snapping indeed as presumed. Also, there's a metal roller the that timing belt doesn't actually spin but just slides along it, like a bearing. It was pretty bent and touching the timing cover. Any know what could cause that?

[usualdeviant]

Are you sure? I mean the valve stems go right down the middle of the valve guides. Couldn't I have bent a stem or two? But either way, now I'm thinking the noise is either that or the head of the valve hitting its seat wrong. Before adjusting the clearance I noticed it was less, like maybe .008 or .009. Might just have to go back and see what happens.

[Madhatter]

They can't hit the guides. The valves bottom out in the seats before going anywhere near the guides.

[usualdeviant]

Didn't know that. But in any case I timed it with the VD on (insert joke here). If it was pinging, it passed emissions better than last time. My engine has killer power, no flatness. More than 200k miles on the clock, by how much I'm not sure. Probably just slightly bent valves hitting the guides in my guestimation. It's a lot of work to pull the head so I'm just going to keep driving it and checking the oil for metal flakes. Eventually I'll rebuild the engine anyway when I have a second vehicle.

[Madhatter]

The dampener doesn't have to be on to find tdc. The crank bolt will hold the hub in position and there is a notch on the crank sprocket.

The rattling noise you heard was probably pinging.

Nasty noises and ticking sounds could be a number of things. In my experience, unless they are well bent and stuck, normally a bent valve means the engine feels a little flat and the rockers get noisy because the valve doesn't fully shut. If you keep driving it like that it ends up burning exhaust valves and you have to pull the head anyway to fix.

So id be finding the cause of your problem rather than driving it.

[usualdeviant]

I'm certain I bent a valve or valves when installing my last timing belt. I forgot that the vibration damper has to be on the crank in order to check TDC. So, drinking boxed wine, I slammed valves into pistons while searching for TDC. The engine still runs and pulls hard, especially since timing the cam correctly and adjusting the valve clearance. However, there is a nasty ticking and a nasty scraping sound, pretty sure that's the valves hitting the guides.

The question is... Will it live? Will the noise get less noisy? Or do I need to get new valves and guides ASAP?

Edit: There is more to the story. After the new belt went on, valve timing was off by one tooth and valve clearance remained unchanged. There was a kind of a rattling sound in the low RPM range. Otherwise everything was fine. This was about a year ago and the car was more or less driven since then with no other related issues. Then I corrected the cam timing and adjusted the valve clearance. That's when this new noise happened. As if the valves got more bent somehow. I strongly doubt that actually happened, but that's what it sounds like. Got a funny look from the guy at the drive through.

[AndrewBird]

24V swap time!

But really, find a used head in decent shape, have it surfaced and replace the valve stem seals and swap it on. You could probably find one at a u-pull-it for cheap and have it checked out by a machine shop.

Either that or check out www.BimmerHeads.com if you want to go all out.

[AwakenNoMore]

Been here as well, happened at low speed, but more importantly, low rpm, still mashed 3 valves and it ejected chunks of the aluminum casting that holds the rocker shafts, had to build another head. With the Bentley Manual it went just fine.

Here's a pic, if this didn't happen you can re-use your head most likely:

[EatsHondas]

Same thing happened to me. New (to me) head and it ran great for a few thousand miles. Then rod knock. Don't know how common it is for bottom end problems to follow a broken timing belt, but it happened to me.

[SkiFree]

Bummer. Well, I wish you the best. You'll have a decent piece of mind once you've gone through the head though.

[tonyloban]

The problem is timing belts on these cars just don't "break" unless they've been neglected service-wise. What I'm saying is there is nothing inherently "weak" about the design, if you're unsure of the last timing belt job it just needs to be done.

I know that. I had the parts ordered and they went on back order. I was getting ready to do it. Just got very very unlucky.

[SkiFree]

The problem is timing belts on these cars just don't "break" unless they've been neglected service-wise. What I'm saying is there is nothing inherently "weak" about the design, if you're unsure of the last timing belt job it just needs to be done.

[redlightpete]

This would be a good time to arrange a back-up car. It makes older BMW ownership a lot more affordable and less stressful. A used head swap isn't that bad a job if you don't have to get it running by the end of the weekend. A well sorted e30 is worth it, so don't give up.

[tonyloban]

I see many of these in your future.

Lol. I'm in college and engaged. This might mean just sell which I REALLY don't want to :/

Decisions decisions