240D, odd stuttering ... clutch?

[BodhiBenz1987]

Here's the latest from the 78 240D 4spd:
I noticed the last couple times I drove it, and particularly today, that after I shift into first or second, I can feel a quick and fairly violent stuttering in the front of the car. It seems to be after the clutch engages when I start to accelerate, and it only lasts about a couple seconds and then vanishes. It isn't immediately after I let out the clutch but a moment after, and it feels like it's engaging OK ... the acceleration is normal other than the "jut, jut, jut, jut, jut." I would say it feels/sounds like I'm driving over several little bumps. It does not do this at any other time ... not in third or fourth, and not while I'm driving along in any gear, even if I slow down. I did a search but most of what I find involves bucking, and this doesn't really feel like bucking. I'm new to driving stick, but I've been doing really well with it lately and haven't changed anything I'm doing.

No real hurry here ... I'm in the middle of brake overhaul Part II + steering linkage mania, but would be nice to get some ideas so I know what I'm dealing with. I love this car, but so far, it really does not love me back.

[rs899]

I must say, it does sound like bucking to me. It does this regardless of engine speed? Try increasing your revs as you let out the clutch. Is your driveline (flexdiscs/center support bearing ) inspected and in good condition?

[moon161]

Motor mounts or throttle damper. Accelerate real easy thru 20 mph, then you're ok.

[BodhiBenz1987]

Originally Posted by rs899

I must say, it does sound like bucking to me. It does this regardless of engine speed? Try increasing your revs as you let out the clutch. Is your driveline (flexdiscs/center support bearing ) inspected and in good condition?

It's different from bucking I have experienced in the past in that it's a more rapid pulsation, and it doesn't really shake the whole car. Maybe it is bucking, and what I'm thinking of is lugging. But it's a quickfire pulsation under my feet in the front. I did inspect the driveline on prepurchase and then again in my driveway and everything looked pretty clean and crack-free ... but it wouldn't be the first thing I missed on this car, so I'll give it another lookover.

[BodhiBenz1987]

If it clarifies the sound/feel at all, my initial reaction was that it was a wheel or brake-related problem ... like something wasn't right with the right wheel. However, the fact that it only happened right after a shift and only persisted for such a short flash makes me doubt that ... and it doesn't happen at all after that initial post-shift bout, regardless of speed or rpm. I'd have to think a wheel or brake problem would persist at a certain speed or be intermittent. Maybe I'm wrong? I've done a lot of work on the front brakes and steering linkage since I got the car.

Oh well ... downpour will keep me from doing the rear brakes for a couple days, so I won't be able to experiment with the shifts for a while. A little break won't hurt anyway.

[t walgamuth]

It does not sound like clutch or brake problems to me.

I would look at my fuel filters.

[rs899]

I would look at my fuel filters.

Never hurts to check your filters, but fuel issues tend to present themselves at high fuel flow times, IMO, like flat out highway running.

Since you have limited shifting experience, get your dad or someone else who really feels comfortable with a stick to drive it and see if the problem occurs. I still tend to think it's operator error...

[Shawn T. W.]

Originally Posted by rs899

Never hurts to check your filters, but fuel issues tend to present themselves at high fuel flow times, IMO, like flat out highway running.

Since you have limited shifting experience, get your dad or someone else who really feels comfortable with a stick to drive it and see if the problem occurs. I still tend to think it's operator error...

If it is OE, then have someone who has been driving a standard watch you drive . . . they should be able to give you some hints if your doing something wrong . . .