1981 240D with A/C. This is the type of A/C compressor that is below the powersteering pump.

I've been trying to get the belt onto the pulleys, but I can't get the A/C compressor to move to the end of its adjustment. I loosened three main bolts, and loosened the adjuster.

I can pry the compressor over about 1/4 inch but there is still atleast a 1/2in of travel left. Am I missing something? It seems as though the A/C lines could be holding it back.

It's been a few years since I touched one of these, but as I remember, the hard line that goes up from the fitting has a strain relief bracket that has to be loosened for full adjustment travel.

Just keep looking at both hard lines on the manifold and disconnecting things until you get it to move.

Good luck,

Thank you for the reply. I believe I had the bracket loose. We ended up turning the fan while holding the belt on, and it popped on. Not sure how he was able to get it on, but my father has alot more experience than I do...

I know you got it done. But it should not have been that hard.
The 240D set up is identical to the 300D Turbo. Loosen the 3 rear bolt heads on the back of the compressor. Just enough to allow the compressor to pivot. Then as Larry has said the compressor hoses are held in position on the left frame rail. Loosen the clamping bolt to allow the hose to move. the hose manifold is clamped to the rear of the compressor, do not loosen this bolt unless you want to lose your freon. But on the side of the compressor against the frame rail of the engine compartment is the clamping unit. Allow the hose to move and the adjusting nut cam then be cranked to loosen the compressor.
Putting on the belt is not a walk in the park but it does go on easily if if everything is loose.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

Yes, it really should have gone on much easier, since there was plenty of adjustment left. I don't recall the A/C lines being clamped to the driver side frame rail.

You are correct, it is next to the frame rail. It bolts to the compressor mount. See the picture below.

Dave

Attached Thumbnails

   

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

I'm still curious about extracting the other half of range of adjustment. It would make the job much easier in the future.

I remember the A/C clamp/bracket being in a spot where it did not allow the A/C line to slide through anymore. That was probably preventing the compressor to move. I don't know why it was at the end of its range of movement, though. You can see this in the 1st picture. The bracket interferes with the bend in the A/C line.

I am a newbie to MBZ and I too did this repair and had the same exact problem, where after loosening the 3 pivot bolts, and almost removing the tensioner bolt, the A/C compressor would pivot a little but not enough to get the new belt on. After an hour of inspection, I thought it might be the Oil Lines bolted to the compressor so I just removed the retaining bolt (9mm I think) so the compressor was free of those. Sadly it wasn't the issue. Upon further inspection, I suspect its actually the compressor lines themselves that are restricting the movement the A/C compressor. They are routed quite complicated and are bolted all over the place to hold them steady. You don't want to remove those lines from the compressor and unbolting them looked like a chore (perhaps its not but it looked like it on my '83 300D.) So there is no easy answer to get the full play in the A/C compressor. However there is a TRICK to get the belt on - at least it worked for me. Its the same way I use to re-attach the chain on my no geared bicycle (1974?)

With the new belt around the AC compressor pulley, put as much belt on the engine pulley (2nd channel counting from the front) from the BOTTOM and keep working your way up pushing the belt on more and more while pulling the A/C compressor toward the engine pulley. At some point, you will max out pivoting the compressor and stretching the belt. If at this point, the belt will stay on but is not all the way on, you should be good to go. Simply crank the engine over once or twice. The belt should feed itself onto the engine pulley. Done.