Shake, rattle and roll

[J. Huber]

Recently there was discussion of a shaking Pagoda. It would idle smoothly then shake when underway. I seem to have an opposite problem.

Yesterday, I started up the 230SL with the hood up. Started right up and basically idled smooth (a little fluctuating but generally in the 900-1000 range. When warm it settles in at about 850). Anyway, I noticed the whole engine was shaking pretty noticeably. I eventually closed the hood and was on my way to the Post Office. Once there, I was curious and looked again. Now it was idling like a happy kitten -- no real movement except my battery was a little jiggy. What do ya suppose makes it so shaky at start up?

James
63 230SL

[Ricardo]

Hey James
Assuming your motor and tranny mounts aren't shot, although it probably wouldn't make a difference, I'd guess that your engine is idling roughly until warm, as in one or more cylinders not getting sufficient fuel. My pump was rebuilt last year and yet I still have a rough idle for approx. 20 seconds from a cold start...check valves leaking back maybe or slight restriction in old injectors or lines....
Richard

[J. Huber]

Ricardo -- I think you are on right track. All new mounts. I think it was Joe or ADalton that has mentioned that hunting a bit on start-up could be an injector prob. And that semi-starvation can cause whole block to shake?

James
63 230SL

[n/a]

James,

I think you are worrying too much. What's a little shaking when the car is idling cold?  The temperatures were dropping the last few nights and I am sure your baby was a little cold.  I have not started my car since last Sunday and I am sure it will do the same thing during warm-up tomorrow. It should be a nice Pagoda weekend though.

Louis 70 280sl Red Auto

[J. Huber]

Thanks Louis. Believe you me, I am just curious -- not about to mess with the fuel injection pump any time soon! Too long between drives and I start to shake a lot worse than the car!! Our weather has been fantastic as well -- Fall is generally my favorite time of the year.

James
63 230SL