Throttle bushing retaining pin

While driving my SEE from one location to another awhile ago, I noticed I had lost a few hundred RPM. The pedal would go all the way to the floor and I got 2000 RPM at best. Reading through the manual it looked like I needed to shorten up the throttle linkage on the injector side of the engine. There are fuel hoses, some sort of oil sensor that I think is part of the diagnostics system and injector lines in this area so getting at the linkage is difficult. I got things where it needed to be and just needed to insert the retaining pin that keeps the ball socket on the stud. I had pair of hemostats on it so I wouldn't lose it but while sliding it in place it launched into space. I spent quite awhile looking for that darn clip but figure its gone for good. Anyone go through this and find a source for clip? Its figure 38 Item 13, PN 017805 010403. I get some hits when I search for it from Mercedes but it calls it a ball socket.

Once I find a source I am definitely buying spares.

To close the loop on this one Couch Off road has them in stock for around $1.50 a piece. As I noted these are very small springy objects in very tight quarters (unless you lift the cab). I don't think you could even get at the other end of this throttle shaft which has the same clip where it ties to the linkage that runs through the engine block. I strongly suggest getting some of these clips before you delve into adjusting the throttle or pulling the injection pump as the odds of getting the same one back in place is poor.

Thanks for finding a source for these clips. I wimped out the other day on the adjustment of the linkage when I realized how tight the access is.

I think we need to start a thread on all the things someone should work on if they go to the trouble of tilting the cab. One of them definitely would be throttle adjustments.

Scott at EI also has them. Its odd as I checked the website first and did a couple of searches using the part number and NSN with no luck.

Here is a link with photo of the beast.

https://expedition-imports.com/071805010403

peakbagger said:

While driving my SEE from one location to another awhile ago, I noticed I had lost a few hundred RPM. The pedal would go all the way to the floor and I got 2000 RPM at best. Reading through the manual it looked like I needed to shorten up the throttle linkage on the injector side of the engine.

Click to expand...

Okay, I'm curious about how it could get out of adjustment in the first place. Linkages generally don't grow or stretch, so if it was fine to start with, what happened??

Darned if I know. Given the crappy access its hard to run down.

Well I got my RPM back which was the purpose of the adjustment. Previously I was limited to 2000 RPM. It now revs just shy of 2400 which I believe is the stock max RPM. I realize that the engine is capable of much higher RPM by adjusting the injection pump but realistically stock RPM is fine.

Prior to removing the spring clip I had tried to pop off the linkage from the ball. I didn't have good access to pull on it directly but I yanked on it pretty hard and it didn't pop off. I cleaned out the cup on the linkage of a 30 year mix of lubricant and dirt and put lithium grease inside. With the clip installed it took me two tries to pop it on but its on there.

I will keep an eye on it and if I lose the RPM again it means tearing it the rest of the throttle assembly

peakbagger said:

Well I got my RPM back which was the purpose of the adjustment.
........I will keep an eye on it and if I lose the RPM again it means tearing it the rest of the throttle assembly

Click to expand...

Once we lost RPMs to idle. The butterfly/lever (on the engine compartment side) from the foot throttle pedal axel
rip off. The weldseam was broken. If you get off the plastic bushings to each side you get the axel with lever out.
Check this if you have still or again the problem.

Thanks for the warning. I expect you may be onto something as it shouldn't have required the adjustment.

Yes, I agree with Flufarm that normally there is no sudden lenght change at the rods.

After my hand hand throttle issue I had this weekend I got under the SEE to take a look. The bell crank that is attached to the accelerator pedal from the hand throttle (#23 on the parts drawing 0040 00-2, P/N 406 300 09 04) is bent. What should be a flat plate perpendicular to the shaft centerline is curled like a potato chip with both arms bent inward, thus the relationship's of various components is off which probably reduces the stroke on the roads going to the injector pump. One arm connects up with the hand throttle linkage (#28 and the other and has the roller (#21) that rolls on the remote control lever (#15). The roller is no longer aligned with the remote control lever face and the hand throttle arm is bent enough that I expect the threaded rod end popped off the ball stud. I could reach up and bend the bell crank to get the roller to track better but I expect that its not a permanent fix.

This is probably a primary cause of losing RPMs that required the throttle linkage adjustment. Of course Migginsbros had replied that this part had a torn weld on his truck so that's a possibility that's its not bent rather a weld is cracked.

I have decided to order a new bell crank from Scott at EI as well as a new threaded rod end and a throttle bushing. Interestingly the parts breakdown does not show the retainer clip that was used on the threaded rod end at the fuel injection pump even though the part number is same for each one (991 24 22). Luckily I bought spare clips in case I can use one on this end and have a new threaded rod end on order. I expect I will be revisiting the injector linkage adjustment to put it back to where it was. It looks like if I remove the alternator access cover and the alternator I can get my hands in there to work on this linkage. I can see it from underneath but its a long stretch to get to everything. I expect someone with a lift might be able to get at it from underneath easier.

A general note, over the couple of years I have had the SEE and reading various forums it looks like these components were under engineered out of the factory. The first SEE I looked at had a screwed up throttle linkage and given the number of reports out there its looks like this was not a one time issue. I also see various sellers selling parts for the hand control assembly so that's another indication. Possibly a good spot for some entrepreneur to come up with a heavy duty version. On my 1300L there is no manual control lever, rather its a knob on the transmission plate that screws in and out to adjust RPM. In order to shut off the engine, I have to push down on the knob or lift up on the accelerator pedal.

I think that long rest periods and a lack of lubrication combined with heavy military boots is what turns FLU throttle linkages into pretzels.
And by "military" I really mean GP personnel. It seems that when faced with a stuck injector pump, stomping harder on the throttle is the answer.

Who knows what or how my rig was used previously. The linkages have always moved since I got it but there was an intervening owner and I hit my linkage with lithium early on. If you look at the design of the shaft and the attached bellcrank, Mercedes is asking a lot of a cheap nylon bushing that is supposed to take a lot of side loads. Ideally it should be supported at two points on the shaft instead of hoping that the bushing can deal with overhung load. It would also help if the bellcrank was thicker as I shouldn't be able to bend the arms with my hand.

I think they intentionally put in heavy springs on all the linkages to deal with rough roads which probably doesn't help. Overall the entire assembly sure looks Rube Goldberg to me. Of course I am not a Mercedes engineer so any input on the design will be ignored.