Procedure 07.1-220 shows how to replace the engine stop vacuum unit but it doesn't show that the ALDA is in the way. Is it possible to detatch the ALDA from the IP? What size wrenches do I need? Is it possible to remove the electrical connector beside the engine stop vacuum unit? I haven't figured out how it comes out.

Thanks,
Sixto
91 300SE
87 300SDL

Sixto:

Just did this last year on the 300D. Easy, better on the SDL that the W124, too.

You can remove the ALDA by unscrewing the captive nut on the bottom. I used two large Cresent wrenches, too hard to get regular wrenches in there. If one is thin, that is best. Nut size seems to be around 19 mm. I had to remove the windsheild washer tank, you don't.

When you get the nut loose (the nut is on the bottom, I think, hold the ALDA with the other wrench -- but it was a year ago, it will be obvious if I have it backwards!). You will have to tilt the ALDA to get it off the fitting, you cannot lift it straight up far enough. Wriggle it about, you will find the magic motion eventually.

The electrial connection to the rack sensor comes off by rotating the lock tab counterclockwise. It will be very stiff, since it hasn't been moved for eons. Plug pulls off once the lock is open

The screws that hold the shutoff down are Torx fasteners, and will be stuck. You can bang on them to start them, but go easy, the pump housing is aluminum (this is why they are stuck). Use anti-sieze on them going back in.

Shutoff is held down by two screws via strap clamps. Pull the gasket off the old one, there isn't a new on in the box with the new shutoff. Make sure you get the metal one, I did -- the plastic one may or may not work, it fits, but I like the metal better.

Make sure it is hooked onto the guts of the IP -- stop lever must come up, and operate with vac.

20 min job in a W126!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

You don't need to remove the ALDA to do the job if you don't mind fussing. You should remove the rack pin sensor wire as mentioned above. To get at the 10mm nut nearest to the ALDA it will take a few extra minutes because you can't move the wrench very far each time. I used a curved wrench and patienace.

Brian