But... after installing "fuel line bushings" on the throttle fork and jamming it PROPERLY back into the spot it was supposed to go, through the 2 little slots on the STOP Lever linkage, I only have half throttle. The little "hammer head" does not make contact with the IP stop screw at full throttle via the pedal, but it does make contact when I pull back the STOP Lever.

I'm suspecting that I need to adjust the length of the rod that connects this assembly to the IP.

Am I on the right track here?

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The term "Fuel Line Bushings" draws a zero with me; is there another name for them?

For My own year and model all of the Linkage Rods have a specific length specified in the Mercedes Service Manual.

Someone would need to post the .pdf with your specific linkage or post a site were you have access to the manual online. I am at the Library and don't have access to my notes to be of help with that.

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84 300D, 82 Volvo 244Gl Diesel

Turns out that the pivot mount bushing thing on the firewall is the issue.

By fuel line bushing I mean the throttle linkage gubbins where the fork slides into the stop lever assy, I put fuel line over the fork and jammed it into the slots since both of the gubbins were gone.

For the time being, until the pivot mount bushing comes in I have pulled the fork back, turned it and placed one of the forks over the stop linkage so it pushes down and makes full contact with the screw on the IP, giving me back full power until I can get it right.

The two parts you need for the linkage fork are about the cheapest parts Mercedes benz sells. They just seem to rot with age. The fact that they are rubber might have been to reduce transmitted noise. The index box that I keep these odd ball part numbers on cards is not where it should be at the moment.

I figured that heat shrink tubing might be built up to replace them. Just shrinking and inserting more over the previous shrunken heat shrink tube until the right thickness is built up.

is to not touch the linkage adjustments. Replacing your worn rotating and sliding components should restore normal operation.

The linkage is factory-adjusted and should never (even 35 years later) need adjustment unless of course you have willy-nilly replaced adjustable components.

Almost everyone who tries to adjust rod lengths to correct starting and idling problems gets into trouble.

You cannot tell what some prior owner did to the linkages in 30+ years of service.

I had never test drove my Mercedes and the Seller drove it to my house. When I drove it acceleration was so slow it was scary to leave a stop sign or Traffic Light. However, once up to speed it ran fine.

It turns out the linkages way to much play in them. Nothing was worn out so I doubt if it came that way from the Factory.

If you have an auto trans the Throttle Linkage Lengths determine when the Bowden Cable is pulled.

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84 300D, 82 Volvo 244Gl Diesel

I had a similar situation this past weekend with my 1983 MT 240D project. I finally got around to looking at the throttle linkage. I've never been able to get more than 25% throttle out of the car (it's been a project since 2012, and I haven't done more than drive it in and out of the garage).

As I said, I suspected a throttle linkage issue. I disconnected the linkage rod that goes to the injection pump, and activating that manually, I was easily able to get full throttle.

I reconnected the throttle rod and looked for the problem. Like MyOld240D, I was missing the bushings into which the fork from the throttle pivot are supposed to slide. So, like him, I also fitted the pivot fork with sections of fuel hose.

This did nothing to solve my problem. So, I played with the throttle a bit and found it was hitting a limit stop. Specifically, the top-most rod in this picture was the problem. it was hitting the limit stop on the pivot bushing bracket.


So, I disconnected that rod and adjusted it longer. It didn't take much, and now it seems to be OK. I'm not sure why I needed this adjustment, but it may be related to the disconnected idle control cable (this is how I got the car). I'll be turning my attention to that soon.