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Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:07 am
by MMCGARAGE
Salutations Everyone, The mileage on my 1988 420 SL is 318,000, however I had to replace the engine a decade ago due to a broken timing chain. A 1989 420SE served as a donor engine, and my friend and I are now repairing it because it, too, had a timing chain problem. Two valves snapped and two others bent; all damage was contained to a single bank; the chain skipped and a piece of the guide became stuck between the sprocket and the chain. We have taken the n/s bank apart, skimmed the head, changed the valves, and are presently reassembling it with new chain, tensioner, and guides. Despite the abundance of high-quality films covering topics such as vacuum circuits and throttle linkages, we are still having trouble getting everything to fit properly. We'll figure it out, but it would be helpful if someone could explain the suction system and the throttle linkage in simple terms. Right now, the most pressing problem is that we're missing a component and have forgotten where it fits. (never mind attempting Gemini AI) We suspect the throttle linkage, however we are unable to determine its precise location. Given the given photo, does anyone happen to know what it is? Also, I've included some pictures of the engine work in progress.

Re: Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:08 am
by madmadmax
Is that a bracket for raising the engine?

Re: Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:08 am
by ELDORADO4TRUCK
Seems like that to me

Re: Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:09 am
by MMCGARAGE
Much obliged. Being barely 50 mm in length, I find it hard to believe it might serve as a lifting bracket; yet, I could be completely mistaken. Although its intended use is not immediately apparent, we deduced that it had something to do with the throttle linkage when we removed it.

Re: Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:09 am
by Diveintothebluee
I will examine the throttle linkage on my W126 and provide an update either today or tomorrow.

Re: Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:10 am
by MMCGARAGE
It is very appreciated. Thank you.

Re: Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:11 am
by madmadmax
After spending twenty minutes poring over throttle connection diagrams online, I've come to the conclusion that you would have perished if I had been at NASA during Apollo 13 and this assistance was what you required.

Re: Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:11 am
by MMCGARAGE
I went through the exact same thing and I just couldn't come down from that high! 🌏

Re: Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:12 am
by ELDORADO4TRUCK
Wishing you the best:

Re: Recognise a component from a 1989 420SE

Posted: Mon May 18, 2026 11:12 am
by ELDORADO4TRUCK