300TD Darth Vader... and another concern... UPDATE: FIXED! mostly...
 

I've got a couple noises in my engine that seem abnormal. Perhaps one of you guys with some awesome noise deciphering skills can give me a clue to what's happening here.

The first concern is the Darth Vader syndrome;
http://www.youtube.com/watch?v=RcDTZcLcMnU&feature=channel_page

The main reason I'm concerned is that there was a BIG "exhale" from there after shutoff when the engine was very warm.

Next, is the knock (can also be heard in the Darth Vader);
http://www.youtube.com/watch?v=5xlZgQrSnQk&feature=channel_page

The knock in the video sounds most accurate to reality at the 35 second mark. This knock ONLY happens after the engine is warm, and the car has been driven fast. When cruising around in the neighborhood after startup, this does not occur.

Lastly, there's a rattle... maybe the turbo? Didn't translate well to video;
http://www.youtube.com/watch?v=VbU8KuS6cn0&feature=channel_page


Injector service is high on the priority list. I think that should help with some of the noise you're hearing.... Anyone else hear something more serious happening? Let me know! I'll be selling the old beast soon and would like to make sure she's in tip top running condition.

Thank you!

Yeah, the knocking is much more apparent in the Darth Vader video; right at about 10 seconds.

Aw... c'mon! I know one of you guys knows what's going on here...

did you adjust the valves at all?

the turbo noise could be a bearing.

To pin point where the noises are coming from you should get a stehoscope at your local autozone.

sound bytes leave much to be desired... its nearly impossible to give accurate diagnosis in digital form.

I hear boost happening, the impeller blades might be worn / damaged. The knocking be anything from a simple predetonation to a compromised bearing. Take care of your regular maintenance items before jumping to conclusions.

Regular maintenence; check...


So worst case scenario; if there's a bad bearing, what are my options??

if you determine there is a bad turbo bearing you can rebuild the turbo for about $85

I'll assume there's some resources here on the site for turbo rebuilding details?

Anyone know if the darth vader "exhale" out of the air intake is normal?

Well I pulled the injectors and WHOA!!! they're nasty... Crud all over them. When I pulled the injector closest to the firewall, there was a bit of a burning smell. I think that's a bad thing, right?

What regular maintenece (sp?) has been done? Diesel purge? valve adjustment? Have you really looked at the turbo? Can you post pics of the impeller? Have you checked to make sure the turbo shaft does not have a lot of play? As others have said do simple things first and check everything...then come back and we will give you a worst case. Not trying to be difficult but throwing parts at these cars is a very very expensive idea. Burning smell...when did you pull the injector...i.e. how soon after you shut the car off...might just be residual combustion reaction.

I'll post pics of the turbo soon. I have yet to open it up.

I'm waiting on some new injectors, and I also have a valve cover gasket so valve adjust is pending... As far as I know, it's been a LONG time since these things have been maintained...

I pulled the injector 1+ days after it was run.... hopefully not a bad sign.

Thanks for all the help so far guys

That clanking is bothersome. It sounds rhythmic.

Get your engine to temp, record a stable idle RPM, and count its occurrence within a 3 second interval. (or any number of seconds that is a multiple / factor of 60)

I'd love to, but I have the injectors pulled at the moment. With any luck, the regular maintenance I'm doing now with cure it.

What will the frequency of the clank indicate?

Clank could be a rack dampener bolt or on the more serious end a spun crank bearing.

Not that this is the source for the noises, but while the injectors are out, change the glow plugs and ream the holes if they haven't been changed lately.

The frequency will allow you to diagnose more accurately which part or parts are involved. If we know the engine speed, we know the rate of all moving parts and their time based actions.

I am concerned about the vacuum pump.. but I am not jumping to conclusions.

Did that one last year. Good call though!

So bro; worst case scenario... what does fixing that bearing entail? It's probably something I'd leave to a pro... just wondering how involved the repair is.

There's no doubt this thing needed some serious TLC.

100% of the valves were too tight. I got up early this morning (before I had to run the kids to daycare) and did the valve adjustment. The nice thing was that since I had my injectors and lines pulled out I didn't need those fancy offset wrenches! Just a regular pair of 14mm's did the trick!

Anyway, valve adjustment was loooong overdue.

It doesn't sound like it's coming from the pump. I recently replaced it anyway and it's been fantastic so far. The first time I just "repaired" it, but apparently I overtightened something inside that caused the center of the pump housing to bust out! I ran to the pick a part and robbed a new (old) one and re-used my brand new check valves.

Unfortunately at the moment my tach is inoperable. I'm this close to sending Mr. Myers $46 for one of his awesome new ones.

Nearly finished installing new injectors/nozzles. The amount of crud under the heat shield in the injector cavity was INSANE! I'll put up a pic of it here in a few mins.

Might it help you guys identify the clank if I take a high quality recording (using a nice condenser mic) and slow it down? I could post both the normal speed and slow speed. This is assuming I will still have the problem after the maintenance I'm doing right now....

Woot!

Done!!!

How about this?? Does that look normal? Ha!

Substantially nasty in there. Anyway, it's all clean now. One big difference (probably due to valve adjustment) is the engine sounded MUCH tighter during cranking. Given that I replaced the injector nozzles, I had the pleasure of hearing it crank for quite some time.

Bad news; the clang is still there. I seem to remember my idle speed being just under 1000rpm, and the clang happens 10-12 times in 3 seconds. Any ideas? (please don't be a bearing... please don't be a bearing!)

Where would this worn bearing be located? I assume somewhere below the piston? I'm going to go check my FSM to see if there's an exploded engine view. I'm just a shadetree guy and I've never done any major engine work so please excuse the ignorance. Hey, we all start somewhere right??

GONE!!!

I just road tested the old beauty and BAM!! Sounds awesome!

Before I got the maintenance done, I had taken her down the highway a few times at 65+ for about 5 mins each time. Upon returning home (overall 10 min trip) the clank would start.

Well gents, I just performed the test again after the valve adjustment and nozzle replacement and was a bit discouraged at first. After a couple revs in the driveway, the clank returned (faintly).... now after I sort of "broke it in", she sounds better than ever! Better still, the Darth Vader syndrome is nearly all gone.

I found a couple other issues: 1) She's running hot (near 100 mark. Used to run a tick above 80). I suppose this is because she hasn't been driven much in the last year and a half... maybe needs a new thermostat. Then again it could be because it's over 100 degrees out here in Houston today! 2) Whining sound coming from the power steering pump area... could be vacuum pump... who knows... 3) I have a BIG vacuum leak somewhere. I bypassed my 3/2 valves hoping to improve the vacuum problem, but that only made it worse. Shifting is crazy right now! Shifting at 3/4 throttle is pretty good; less than that is all whacky. 5) I think she needs a new turbo. Anyone ever rebuilt one of these?

Does anyone have experience reducing the amount of smoke coming out from under the air cleaner? I guess my blowby is now bad enough to make it seem like there's a fire under that thing. If I remember right there's a tube under there with an O ring on it than jams into another tube down to the oil pan. I'll start with a new O ring and see what that does for me.


BOTTOM LINE: I was seriously considering selling the old beast until this situation started improving today. Then I remembered how much sweat and love I've put into this beautiful car... not to mention that the w123 is the best looking car ever made! If I do ever sell this one I'd just replace it with another w123. Everyone in my family thinks that stupid, but what do I care? :D