What did I Break in the engine...

Gonekuku · 03-30-2009, 03:25 AM

2001 325i, Manual Transmission, Bought car at 68K, now 120K. Had belts and water pump replaced since purchase.

First the dumb part: I was borrowing the wifes car... going faster than I should have, dumped into a gear lower than I should have, the engine stalled (Driveline introduced over RPM's ?). After this at first the engine would not crank over. The next morning it did. It ran very rough and I heard very uncomfortable crunching sounds from the engine and I shut it off.

I have the valve cover off, chain tensioner doesn't have visible wear. Sprocket teeth appear healthy (I've done plenty of chains in GM cars), but I'm not having any luck verifying that the cams are properly lined with the crank.

Looking for input on where the damage could be and how to find it. Do I need the cam alignment tool to verify cam timing? If I've skipped any teeth, how many bent valves have I bent? Should I perform a compression test?

The Smart part? I'm here asking for advice !!

Jared at Pelican Parts · 03-30-2009, 07:53 AM

Can you describe the sound better? When did it occur?

Gonekuku · 03-30-2009, 08:13 AM

Definitely a metal on metal sound, and a rough running engine sound. Didn't leave it on long enough to try to locate source. It was a "rough" idle. Not sure if it was because of mechanical friction or improper timing.

It sounded just like both of these horrible sounds:
a) a GM engine with a skipped timing chain
b) a broken clutch in a Toyota truck

I'm thinking a compression test will tell me a lot more? But at the same time probably not the difference between skipped tooth or bent valves.

Jared at Pelican Parts · 03-30-2009, 07:17 PM

If you cant get the plug out, you may have internal damage...

Gonekuku · 05:04 AM

Compression test on this engine (cold) yields grim results...

Cyl - PSI

1 - 54
2 - 0
3 - 89
4 - 0
5 - NA (Stuck plug)
6 - 0

Is it safe to continue assuming a timing chain skipped a bit? I'm green on BMW's and valve clearance for the M54 engine. Looks like I need to order the double Vanos cam alignment tool regardless? should I check the alignment, adjust if needed, then recheck compression. At that point if valves are bent, it would probably be obvious from the compression test? Or, is this already an indicator to pull the head and plan on a trip to the local valve straightening shop?

Jared at Pelican Parts · 03-31-2009, 07:48 AM

Sounds like you seriously damaged the engine. You can't straighten valves BTW. I'd guess that most of them must be broken anyway. You probably have holes in the pistons as well for those kinds of readings. Either way, the head must come off.

Sorry

Gonekuku · 03-31-2009, 06:33 PM

You are so right. if all 4 cam lobes are up on the 0 PSI cylinders and I blow air through the plug hole - there's no pressure build-up. I'm now prepared for at least 6 bent valves.

Head is coming off. Piston news in a day or two.

Thanks Jared !!

AGI · 04-10-2009, 03:28 AM

Why don't you take a 27 and crank the engine by hand to see what's going on. I'm guessing you're having quite a few tappets off the valves, which means cams off realigning, timing and assembling. Also, if your lucky your VANOS have slipped a bit and you're off timing. I would've tested this before ripping all apart.

Jeron · Jeron's Garage

The Money Shift

At least that's what the kids are calling it these days.

Sorry to hear your misfortune. If you want to hear likely scenarios and see some DIY's the search for Money Shift on the web or in bimmerforums.