shake, my imagination or

[chuckr]

hi, i'm somewhat new to MB diesels, i look at the engine while idling, and it is barely moving - sounds real smooth, lots of power, but in the car, idling, it feels like it's moving a lot, the idle is rock solid at 850 or 900 rpm...when i shut the engine off, it jerks like crazy. do i need engine mounts/shock? and is this a DYI proj? how long could i wait to do it?

thanks, Chuck

[bustedbenz]

Originally Posted by chuckr

hi, i'm somewhat new to MB diesels, i look at the engine while idling, and it is barely moving - sounds real smooth, lots of power, but in the car, idling, it feels like it's moving a lot, the idle is rock solid at 850 or 900 rpm...when i shut the engine off, it jerks like crazy. do i need engine mounts/shock? and is this a DYI proj? how long could i wait to do it?

thanks, Chuck

Either is possible. They all vibrate on shut down a little. That's not unusual. If it's trying to jump off its mounts, that's a different story.

850/900 is way fast for an idle. My slightly different engine idles at 630 (deliberately set there, but that's the factory recommendation) and comfortably idles even slower than that if set to do so before it starts to shake a little. I think yours is... well, somewhere in the 600s anyway.

Not impossible that mounts have disintegrated after this many years and miles. You just have to decide how bad is too bad. Watch the engine at idle. You can tell more visually than by the feel of it in the seat.

EDIT -- Just realized that you already watched it and said it doesn't move much. I'd say that's good enough. I expect you're just not used to diesels. They all shake the seats a little. it shouldn't be... objectionable... but it is different compared to gas engines.

[toomany MBZ]

Yeah, idle is supposed to be ~750.
But that won't have an affect on the shut down, does it shut off quickly?

[chuckr]

thank you guys. yes, shuts off very quickly. you are right - I don't think i'm used to diesels yet. I have had this car for only about 3 months and am working on it. it's incredible, i love it. it just seemed to shake more than 'before'. like i said, could be my imagination. i'll investigate lowering the idle a bit. chuck

[POS]

I don't think I've ever bought a w123 diesel that didn't need motor mounts - they all seem to collapse after three years or so, and most previous owners don't even think of changing them out. Now, when I get another one (like the black one I just bought), new motor mounts are part of my standard list of things to do.

[theo3000]

Originally Posted by chuckr

thank you guys. yes, shuts off very quickly. you are right - I don't think i'm used to diesels yet. I have had this car for only about 3 months and am working on it. it's incredible, i love it. it just seemed to shake more than 'before'. like i said, could be my imagination. i'll investigate lowering the idle a bit. chuck

Mine shakes more as the ambient temps go up. Did all the fixes - nothing helped. Learned to live with it.

[toomany MBZ]

^ You may want to adjust the rack damper bolt.