Driveshaft collapsing - Page 2 - PeachParts Mercedes-Benz Forum

Diesel911 · #16 06-07-2014, 12:25 PM

Quote:

Originally Posted by crazy4diesel

These fit up in there? Excuse the dumb question, but I don't really understand how this shaft works. These nuts do what exactly? The shaft extends and collapses, beyond just sliding on the splines?

Both drive lines I removed from my cars, just came out, because the shafts just slid back and forth on the splined connector. But, I had the manual shaft rebuilt, and now it doesn't move at all.

I always assumed that the reason for the shaft beaing able to collaspe was so it could be removed and installed on the vehicle especially because the Centering Bearings on the Flex Disc ends need to be cleared.

Before the Drive Shaft Collar is tightend the Car is supposed to be put on all 4 Wheels and rolled back and forth to adjust the Shaft Length and then the Collar is supposed to be tightened to a specific Torque.

With the Collar Tightened all of the side play in the Splines is closed and that keeps the Splined from wearing.

During th rebuild they likely tightend The Collar.
Also the sections of the Drive Shaft are supposed to be match marked.

In the Picture te Flex Disc is remved and yo can see the Centering Bearing on the righ and the Rod that stick out that goes inside of the Centering Bearing on the left.
You need to collaspe the Drive Shaft enough to get that Rod out of the Centering Bearing so the Drive Shaft can be moved sideways.

Front and Rear had the Same Rod and Centering Bearing.

The Centering Bearing inside diameter needs to be checked for roundness and it needs Grease.

Stretch · #17 06-07-2014, 01:07 PM

The main thing to remember about this design is that when the wheels go up and down the differential does not go with them like it does on a horse cart sprung live axle affair. The engine, the transmission, the propshaft and the differential should all be aligned on the same axes. They should be in one long line.

Whilst the splines help with removal and fitting they are also there to make up any discrepancy between the position of the flex disc on the differential and the position of the flex disc on the transmission / gearbox. Imagine building thousands and thousands of cars and imagine how much the position between these two points could vary between car and car and car and car...

...bung in a splined shaft to make up the expected tolerance in all of those gaps.

(Now don't mention that single UJ)

crazy4diesel · #18 06-08-2014, 01:24 AM

I got it loosened with a pair of channel lock pliers with duct tape on the teeth. Worked great, and have both flex discs attached and torqued. Now, before I tighten it back up, the car us supposed to roll back and forth a bit, is that right? Once do that can you jack it back up to get back under it, or does that put the shaft back out of whack again?

Stretch · #19 06-08-2014, 01:27 AM

Quote:

Originally Posted by crazy4diesel

I got it loosened with a pair of channel lock pliers with duct tape on the teeth. Worked great, and have both flex discs attached and torqued. Now, before I tighten it back up, the car us supposed to roll back and forth a bit, is that right? Once do that can you jack it back up to get back under it, or does that put the shaft back out of whack again?

That has the potential of putting it out of whack again - ideally it is a four post lift job or up on ramps job.

If you're not a stripped down racing snake and you can't slide under the car, something like a nice high curb near by with two wheels on might do.

crazy4diesel · #20 06-09-2014, 01:10 AM

Quote:

Originally Posted by Stretch

That has the potential of putting it out of whack again - ideally it is a four post lift job or up on ramps job.

If you're not a stripped down racing snake and you can't slide under the car, something like a nice high curb near by with two wheels on might do.

Thanks, that's a good idea, so I can drive it about a tiny bit with the nut loose? It must be not too bad, since when I pulled the drive line out of both the cars, the donor and the keeper the nut was loose, who knows for how long, I bought both cars used.

Stretch · #21 06-09-2014, 08:27 AM

Quote:

Originally Posted by crazy4diesel

Thanks, that's a good idea, so I can drive it about a tiny bit with the nut loose? It must be not too bad, since when I pulled the drive line out of both the cars, the donor and the keeper the nut was loose, who knows for how long, I bought both cars used.

Drive - well - drive isn't really something that you should do...

...I advocate rolling the car to make things settle not knowingly driving with loose bolts. Be sensible - be safe.

Finding those big nuts loose however must have been a bit of a bonus as many people complain about getting them undone!

BodhiBenz1987 · #22 06-09-2014, 07:13 PM

Quote:

Originally Posted by SD Blue

I've used 2 large crescent wrenches from Harbor Freight. I've also used Channelock pliers. Both of these come in handy for a few plumbing tasks, as well. To keep from grrr-ing the nut with channelocks, a quick wrap of duct tape helps.

I've also used crescent wrenches from Harbor Freight ... one huge one for the nut and one JUST big enough to fit over the smaller part of the shaft. I've also used this vice-grip wrench I can't remember where I bought ... I can post pictures of them when I get home, if that helps.

Diesel911 · #23 06-10-2014, 09:09 PM

There should be suggestions as to what Wrenches can be used:

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