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Discussion Starter #1
One of my good friends just aquired a mid 70's Case 406. As with all new trucks, some things are good and some are a bit ugly. It's pretty much rust free, but the electrical system is a mess, and there are lots of bits to do here and there. Biggest problem is that we can't get it through the gate to 3 through 6. The forward reverse lever is in forward position, and the the cascade selector is to the rear(main trans) position. The pto lever is in neutral, though the lower pto is engaged. That's another thing all together, the lower pto doesn't fully disengage, it makes a ratcheting noise like the synchros are just barely engaged. Even with the linkage diconnected. The live pto will not stop with the clutch fully pressed, I think that is the adjustment through the bottom of the bellhousing? Are these each seperate problems, or could they be connected? I've tried lots of things, and it starts to go through the gate, but not all of the way. We just don't want to break anything, this truck was supposed to be shifting easily before, maybe something happened during transit... Any thoughts are welcome. Thanks, Seth
 

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If you can lift up the rubber boot, spray some penetrating oil on the linkage. There also may be a grease fitting there. I have to slap the shifter with my palm to get it through the gate. Once you get used to it it is easy. Also it gets smoother with time.
 

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Discussion Starter #3
I've tried everything I feel wont start breaking things. I'm familiar with the gate on my 6 speed 416, but am not sure if the 20 speed is different. I know that the travel between reverse and forward is shorter on the 20 speed than my 6 speed. Not sure what else might be different. I've tried to nudge it to the right while a second set of hands wiggles and moves the reverse/cascade/and pto levers, no luck so far. Thoroughly stumped, Seth
 

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There should be no difference in gate resistance between a 20 sp and 6 sp. You're shifting exactly the same things.

I agree that it may just be tight from lack of use. Take the boot off and grease the crap out of every moving linkage and gate you see on the shift plate. If that doesn't solve the problem, there are other issues with the main box.

Maybe you've got a hang-up issue with the reverse lockout. I've forgotten if you're supposed to be able to go though the gate into 3,4,5,6 with the reverser lever rearward (in reverse). I'd look at that first.

edit..

Just for grins, have you tried shifting the main box with the cascade control in neutral ?
 

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Discussion Starter #5
In the end it took a HEAVY slap to get it over. Seems like something wasn't quite lined up, as now it shifts through the gate easily. I hadn't wanted to horse on it too hard, as it isn't my truck. Scott had no problems and one good whack got it through. The cascade/main lever still jumps out of the main position though, and the lower pto still grinds when disengaged. Nothing is ever easy. Seth
 

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Passing this on to ya Esde from a soon to be member in this forum

... esde about (your) slow clutch ... I had same problem with my 406. First changed rear clutch slave hose with no change then changed front hose now feels like a new clutch. The front hose was so swollen inside that you could hardley blow comoressed air thru it. Could you please forward this to esde as it would be a lot easier to change hose with cab off.

Ron Sanford,
Volcano Volunteer Fire Dept Volcano Hawaii.
 

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I pulled up this thread looking for help. Yesterday I drove my 406 about 40 miles to pull logs out for fire wood. All went well until I lost the ability to shift beyond 3rd. I can access 1 and 2 nd gears Ok ( with a lot of `fishing around' ). When in the high spped gate I can only get into 3rd and neutral. The shifting has always been stiff and was getting very trickey , with lots of tries etc to get into the gates and out of 5th , then it would run fine for quite a while. I pulled up the exploded view of the transmission off the Russian parts posting, all this did was scare me from just lifting the top cover. I left the truck at the work site as I didnt want the whole state mad at me for driving home at 12.5 MPH. Going back today to remove the top main linkage and see if i can find a bent or severly worn gate / fork pickup arm.
Will keep this post updated on what I find as there seems to be a lot of chatter about this issue. By the way the SEE manuals are not much good as they have what looks to be very much simpiler transmission, not the 6 speed with 4 ranges .
Dave
 

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Discussion Starter #8
Yay, 3 year old post! Dave, lifting the cover isn't hard, but getting it back on right takes some thought and patience. If you take the cover off, and the plate that houses the "logic" (reverse lockout, high-low shift through the gate) you will be able to determine if it's a shifter problem or an internal problem. Bolt the top cover to the shift plate and see if you can run it through all of the shift operations. If you can you'll know that the problem is in the tran$mi$$ion. I recall that there is a set screw in the trans that is known to come loose and let something move, causing you to loose a few gears. The fix was to fish out the screw, drill an access hole in the trans case, and reinstall the thing with locktite. The fix is somewhere in the mog mail list archives, several people have done it, I think the first was Kai Serrano. Good luck.
I have a spare shift plate and top cover if you need one to get it going again.
 

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Thanks Seth, I got the rubber maxi boot off the unit today, and got a much better look at the trans, lot of changes to what I thought so cancel my comment on the SEE manuals, I now plan on bringing the truck home on my trailer and tilting the cab to get the top off. I will take photos of what looks to be a watch makers day dream of all the little slides and pins and junk that passes for shifting permissives etc. Dave PS I will look up the info on the set screw, It feels something like that not a gear or bearing thing, still runs fine , in third.
 

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Discussion Starter #10
Dave, you don't need to tilt the cab all of the way. About 1 foot in the rear lets you get the top off easily, and still have a nice seat to sit in and stare at all of the bits and pieces. Cold beer sits nicely in the base of the passenger seat, and wrenches and such stay easy to find in the glovebox.
 

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Discussion Starter #11
Update? good news we hope.. :)
 

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Guys,
Thanks for the help, also a big thanks to Von who gave me some great advice. The truck is back in service, with all gears functional. Seth, you underestimated the patiece factor, trying to get everything lined up and sequenced took a lot of trial and error as the gears were not sequenced right when I opened it.
The problem was a fracture of the main `slide' which is utilized in the 3-4 and 5-6 linkage. This is attached to the gate mechanism `plate' which sits under the transmission cover and is secured on both ends by a swaged pin and eared T, so removal without new parts was pretty much out of the question. The slide is cast steel and I stick welded it after a V notch prep, with a 120KPSI SS rod.
As for the bending or damage to the forks etc that leads to hard shifting, it would be pretty difficult as these are all substantial steel pieces. My broken part had a old stress fracture displaying the usual smooth faced pattern except for the final fracture point. This is in a machined slot which is the main gate for the shift finger that comes down ito the box from the top shaft and lever assy. There was only a little over an 1/8 in thick area left and the break was at the bottom corner of slot.
I have a bunch of pictures of the work, but this site seems to hate 3 meg photos. Anyone wants to see them let me know and I will send direct. Trucktor, maybe you have some advice on posting photos???
Dave
 

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As far as posting photos, since almost all of the photos I have stashed away
have been harvested off of the internet-they are already in a post-able format / file size for the purpose, so I can just sling them back up.


When dealing with your own photos that are of a size that is too large for the forum to let you load, there are two main ways to cope with the situation.
One is to set your camera to the lower-res end of the scale, so that the photos you take won't be "over-sized" and you may be able to post them this way...

However, they may still bounce back and the quality will suffer at the lower end of the settings.

The other, preferred way (well, I prefer it...) is to take shots at MED to MED-HIGH resolution and then load them into the computer. I work on MACS, so I use IPHOTO. There is an "export" function that allows you to size your photos for posting/E-Mailing, etc etc. There is a "custom" sizing or cropping function and I use that, picking something on the order of 600 X 800 for the image size, and I wind up with good resolution and a file size that will post up.

I'm sure that the PC guys have their system, and I'm sure that there are
programs that will run rings around IPHOTO, but it works for me.
 

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...I'm sure that the PC guys have their system, and I'm sure that there are programs that will run rings around IPHOTO, but it works for me.
There is a discussion on this listed in the Ultimate sticky on top of this board.
 

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Truktor,
Thanks for the advice, 3 megs is my lowest setting. Need to buy program for my MS dos system to size photos.
Coach, unless there is something new on stickey , I did not find anything there that addressed the size problem.
Dave
 

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Truktor,
Thanks for the advice, 3 megs is my lowest setting. Need to buy program for my MS dos system to size photos.
*edit* Wait.......you say you're runnng DOS ??!?!?!?!?!?!?!?!?!?!?!?!?

Nope. If you're running XP, go to this page:

Microsoft PowerToys for Windows XP

..and download the tool called "Image Resizer". When installed, you simply right click on any pic file, select 'Resize pictures' and you'll have 4 different resolutions in which to proceed.

I suspect MS has the same tool available for Vista, if you're running that. There are probably numerous open-source apps available that do this, also.

Enjoy.
 

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....Coach, unless there is something new on stickey , I did not find anything there that addressed the size problem.
Dave
4th Bright Red link in the Ulimate Sticky is an old discussion on shrinking pictures.

one of those ..... if it twas a snake it would a bitten ya things :D
 

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Coach et all. Thanks , I found the resizer, buried about 4 levels down in my photo processing software, and it works! Notice I finally have an avitar,
PS I thought XP was MS DOS based, but then computer skills are not my forte.
DFS
 

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Yay, 3 year old post! Dave, lifting the cover isn't hard, but getting it back on right takes some thought and patience. If you take the cover off, and the plate that houses the "logic" (reverse lockout, high-low shift through the gate) you will be able to determine if it's a shifter problem or an internal problem. Bolt the top cover to the shift plate and see if you can run it through all of the shift operations. If you can you'll know that the problem is in the tran$mi$$ion. I recall that there is a set screw in the trans that is known to come loose and let something move, causing you to loose a few gears. The fix was to fish out the screw, drill an access hole in the trans case, and reinstall the thing with locktite. The fix is somewhere in the mog mail list archives, several people have done it, I think the first was Kai Serrano. Good luck.
I have a spare shift plate and top cover if you need one to get it going again.
ESDE - I know this post is YEARS old! Do you know where in the mail archives Kai's fix for the transmission screw is? I been searching for this information because the cascade shifter on my 1973 Case MB4/94 is beyond "high" position and I believe this is the problem I am having. I am trying to find out how Kai drilled the hole alignment (measurements)...Thanks for any help!
 

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#6 in this post is the write-up on the setscrew that can come loose:
 
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