Author Topic: is my m42 Done for? (Read 7184 times)

fiftytakedowns · « **on:** November 29, 2010, 06:59:01 PM »

Comin back from I-80
My car is starting to make some funky ass noise from the engine bay.

I pull over to a gas station, and I hear waht Resembles rod knock, but it is not so harsh. at Higher RPMS it is almost faint. Anyway, IDling it was making the noise, and I realized Im FUCKED if I get it towed, so I drive the 2 miles up the freeway to davis, and im trying not to freak out from the noise.

anyway, I pull into the parking lot, and it nearly goes away. I couldnt distinguish it from the top or bottom of the engine. but I took an audio file, If you can ignore the very loud rattling of the aluminum flywheel than you might be able to hear it.

If anyone has an Idea what It is, or should I start hunting for a new m42 for when I can finally afford to buy one.

To understand the urgency, I have a job in marin, that I have to commute to on thursday through Monday. and Im nearly done with the 2002, Im just assembling it.

Link:
http://dl.dropbox.com/u/11819570/Memo.m4a

wht would be the minimum I could pick up a m42 longblock for?

YetiX · « **Reply #1 on:** November 29, 2010, 11:24:24 PM »

I suspect that, yeah, you're fucked.

It sounds to me like you're timing chain has shit the house. (That's technical-speak for almost died.) You could try throwing a new chain tensioner in there but . . .

I'd get the 2002 on the road mas ricky-tick.

tonywonder · « **Reply #2 on:** November 29, 2010, 11:41:02 PM »

wow that sounds like shit. you could probably find an m42 for 200-500. but i would check and see what actually went wrong and see how much it would be to repair vs buying another engine. a timing chain isnt expensive but who knows what happened to the internals from the timing chain busting. bent valves and such. goodluck

fiftytakedowns · « **Reply #3 on:** November 30, 2010, 01:02:27 AM »

If the timing chain was fucked, wouldn't it not run. This engine I feel is on it's last legs anyway, with all the problems it gives me. I guess I'm in the market for a new engine, I just need the facilities to do the swap and the way of getting it there.

YetiX · « **Reply #4 on:** November 30, 2010, 10:26:18 AM »

If it broke, the car would not run. If it's stretched out, about to break, and slapping against the guides, etc. it'll make a loud diesel-sounding rattle. That said, sometimes when it makes that noise it's just that the tensioner has failed and replacing it can help things.

It's not that big of a deal to remove the valve cover to assess the level of wear on your chain, etc.

fiftytakedowns · « **Reply #5 on:** November 30, 2010, 10:48:22 AM »

alright, I can do that

fiftytakedowns · « **Reply #6 on:** November 30, 2010, 07:01:58 PM »

NEw findings:

here's how it sounds

http://dl.dropbox.com/u/11819570/blwon%20engine%201.m4a

here's what I found:

I dont know what that little thing is, but It was floating around once I pulled the valve cover

DesktopDave · « **Reply #7 on:** December 01, 2010, 07:45:46 AM »

I don't know what that is...did removing it solve the noise?

fiftytakedowns · « **Reply #8 on:** December 01, 2010, 12:45:41 PM »

nope, you can hear the noise in the second sound file, someone reported that it is a part of the timing chain guide.

VegasKyle · « **Reply #9 on:** December 01, 2010, 03:58:13 PM »

My car sounds a lot like that. When I first bought it I pulled the lower oil pan and found quite a few pieces of plastic in it from the chain guides and a little flat chunk of metal. This was the first clue that my timing components needed to be replaced. I was also getting some noise at 2800rpm or so and went away higher than that. After driving the car home (about 1500mi) the noise all of a sudden got 100x worse and could be heard at all rpm. I limped the car to my house and pulled the valve cover. The chain was intact and the cam gears looked good. I didn't think it jumped time so I ran a compression test to see if the valves got bent and they were fine. What seems to have happen is one or more of my guides and/or the idler gear gave out but not bad enough to jump time or snap the chain.

I suspect something similar may have happen to you. Will the car not say running? I'd do a compression test first (you can rent a gauge from most auto parts stores). Then I would pull the lower oil pan, it's a good idea to check for bolts in the pan regardless. It may give you some clues as to what is going on.

I'm going to replace all the timing stuff on my car as soon as the last of the parts get here later this week. I'd be happy to share the part #s and where I bought everything from if this turns out to be your problem too. I'll be like $400 into it when you include coolant, oil and a some other misc. things I'm doing while I'm in there.

Ryann · « **Reply #10 on:** December 01, 2010, 11:50:25 PM »

Kyle's right. Drop your lower pan and look for chunks. No chunks? Replace your TC tensioner with a new one ($40 or so) and tell us what happens. Your pics are kinda crappy, but it appears as though your cam gears aren't too bad. I bought my car with a similar noise and replaced the tensioner with the e36 version and it's been quiet ever since, even at startup.

dude8383 · « **Reply #11 on:** December 02, 2010, 12:06:10 AM »

That sir is a piece of your chain guide. You gotta remove the entire lower timing case cover to really inspect the damage...otherwise you're just pissing in the wind right now

This happened to me on the highway back in the day, it sounded like a bunch of marbles were being thrown around inside a metal canister. Shouldn't be that difficult, took me abou 2-3hrs replace all of the timing components.

fiftytakedowns · « **Reply #12 on:** December 02, 2010, 02:43:06 AM »

so my engine isnt toast then?

I just want to be sure that my valves arent bent or I something got screwed up elsewhere because of the timing chain fail. anyways, Ill try to pull it, it will just be difficult with the lack of tools here in davis.

Morgan

dude8383 · « **Reply #13 on:** December 02, 2010, 09:01:17 AM »

Quote from: fiftytakedowns;99217

so my engine isnt toast then?

I just want to be sure that my valves arent bent or I something got screwed up elsewhere because of the timing chain fail. anyways, Ill try to pull it, it will just be difficult with the lack of tools here in davis.

Morgan

Morgan, you might have gotten lucky like myself...fingers crossed!

You should be able to do everything with a regular tools, the crank bolt will the only tricky one without the bmw tool.

fiftytakedowns · « **Reply #14 on:** December 02, 2010, 03:08:55 PM »

Quote from: dude8383;99230

Morgan, you might have gotten lucky like myself...fingers crossed!

You should be able to do everything with a regular tools, the crank bolt will the only tricky one without the bmw tool.

Isn't the crank bolt just a 22MM deep socket? and to pull the pulleys you recommend just a crowbar and a hammer I am assuming?

Thanks!

Morgan