cold start missing, then smooth running
 

https://www.youtube.com/watch?v=urw0YMsblX4

Please help me figure out what's going on here. 1984 300d. I've recently done a diesel purge and changed the primary and secondary filters, thinking that might fix the misfires. It stops sputtering after a couple minutes and runs smoothly.

Might be time for a valve adjustment and glow plugs

valves adjusted 2k miles ago, gp checked in car. Probably need to pull them and bench check.

Classic symptoms of a bad glow plug or two.

See here for some ideas:

http://www.peachparts.com/shopforum/diesel-discussion/354874-rough-starting-question.html

Like you I was hoping for the magic fixes that were supposed to come with such advice as adjusting the valves, rebuilding the injectors, and installing new glow plugs, and they all did nothing at all.

Also, if you split a piece of rubber hose and stuff it between the air cleaner and valve cover that'll cut that rattling (I have the same issue). :)

-Rog

If you do a valve adjustment and find several of them on the tight side, another adjustment a few hundred miles later should smooth it out even more.

However, I agree with the glow plugs are likely marginal. It's pretty difficult to really get an accurate check of them with a multimeter.

Before you do anything, do a compression test. I had a 300d that missed just like that when cold. When it was warm ran great. Did a compression test on it cold and it had weak compression. Did a compression test on it when it was warm still low but did raise up.