'87 300D - Throttle linkage plastic balljoint sockets - PeachParts Mercedes-Benz Forum

AlexTheSeal · #1 09-08-2004, 01:42 AM

I'm going to take the intake manifold off my 603 sometime soon, and I want to replace the plastic ball sockets in the throttle linkage (along with the glowplugs and other goodies that are easier to get to with the intake off). FastLane lists two (right hand thread and left hand thread, under "Fuel Injection"), but it's hard to tell from the pictures which are which. As far as I can tell looking under the intake, there are two sizes - small ones on what the CD calls the "accelerator control lever connecting rod," and bigger ones on the "cruise control connecting rod." Can somebody give me part numbers so I can pre-order all four?

Also, any advice what else I should change out while I'm in there, on the general principle of replacing old rubber and plastic bits before they fall apart?

There are a few pictures below. These are all taken (more or less) from the area of the switchover valve connected to the ALDA, with the washer bottle removed. The first picture shows both the cruise control connecting rod (upper green circle marks the rear of the two balljoints) and the accelerator control lever connecting rod (lower green circle marks the lower of the two balljoints). The second picture is just the cruise rod balljoint, and the third is just the accelerator rod balljoint. Yes, there is a small hoseclamp around it, that's why I'm replacing it.

It wants to split open, lose its grip on the connecting rod, and leave me stranded.

speedy300Dturbo · #2 09-08-2004, 02:11 AM

I scrounged up a few pieces of linkage from various older MB's with the metal sockets. They have locknuts on the ends of the sockets, so they can be adjusted to the exact length needed. While you have the intake apart, check your glowplugs and shutoff valve, adjust the ALDA while it's easily accessible, and replace the plastic fuel line clips and rubber bushings. You may as well install a new intake manifold gasket.

TomJ · #3 09-08-2004, 06:57 PM

Quote:

Originally Posted by speedy300Dturbo

I scrounged up a few pieces of linkage from various older MB's with the metal sockets. They have locknuts on the ends of the sockets, so they can be adjusted to the exact length needed. While you have the intake apart, check your glowplugs and shutoff valve, adjust the ALDA while it's easily accessible, and replace the plastic fuel line clips and rubber bushings. You may as well install a new intake manifold gasket.

Ditto. I just replace them with the metal ones from 617's when I work on a customers car, the plastic gets hard and cracks after a while, the metal ones last forever (as long as they're lubed occasionally.)

BTW, am replying to this from the Meeker public library computer while here in the area photoging the Meeker Classic Sheepdog Trials.

AlexTheSeal · #4 09-08-2004, 11:34 PM

Quote:

Originally Posted by TomJ

Ditto. I just replace them with the metal ones from 617's when I work on a customers car, the plastic gets hard and cracks after a while, the metal ones last forever (as long as they're lubed occasionally.)

Cool! Are the 617 sockets a straight drop-in? Same length and threads and everything? What about the longer ones on the cruise control connecting rod (second picture in my original post)?

Mr. FancyPants · #5 09-09-2004, 02:00 PM

Only one suggestion to pass, make sure the lower manifold bolts (the ones hardest to get to) are tight. I had mine off recently and after I put it back on, I thought I had sufficient torque on the lower bolts but because they are not easy to access, I had not gotten them tight enough to pull out any slight overall warp or compress the gasket enough. As a result, I noticed oil weeping by. After I tightened them a little more, no more oil leaks.

I read somewhere here someone suggesting to plane the manifold flat, but might have refered to exhaust, cant remember!

dieseldiehard · #6 09-09-2004, 02:13 PM

I posted something regarding the 603 exhaust manifold being slightly out of flat, may have deleted it at some point. Another member also reported having the same problem.
As for leaking IPs, I obtained the special rubber O-rings and a cover plate gasket from a local Bosch authorized rebuilder (Gus at Pacific Fuel Injection in SSF) for a very modest fee and fixed most of the leaking from my IP while it was off the engine. Its too bad Bosch made them the way they are, old OM617 IP's don't have hardly a problem with leaks like the new models. That bottom gasket is cruel punishment, someone said they were able to replace it, maybe they are double jointed and have a rubber spine, Not me!