603s use the same pump. The only close-to-relevant difference between a 603.96/3.0 and 603.97/3.5 in this case is the extra serpentine belt idler the .97 has above the vacuum pump. Here's the closest I can find; the section for a 91 350SD - http://www.startekinfo.com/StarTek/outside/12253/program/Chassis/43-0618.pdf

Even at no cost that isn't your money's worth. Nary a torque spec. You can check the archives for someone's notes. Here's my version:

- Release shroud from radiator
- Hang shroud on fan
- Use pulley holder or Harbor Freight tool on water pump pulley
- Use 8mm bit to release clutch fan from pulley (easier said than done)
- Remove fan and pulley; store fan upright
- Remove power steering pulley, use a bar against 2 bolts to loosen the third
- Remove serpentine belt
- Set engine to #1 TDC
- Disconnect threaded brake booster vacuum line from vacuum pump; check valve stays with the pump!
- Disconnect ancillary vacuum line (5-way splitter) from vacuum pump
- Loosen 6 10mm head bolts holding vacuum pump to front cover a half turn at a time; don't loosen the 13mm head bolts!
- Remove vacuum pump and gasket
- Check roller coaster cam on IP timer - if not perfectly smooth, post pictures on forum for advice
- Identify and remove 3 13mm head bolts holding gold colored assembly basket to front cover
- Decision point = you have a choice of a metal outline gasket, fiber outline gasket or metal dam gasket. Pierburg pumps come with a dam gasket. A dam gasket is required on early 603s which a 603.97 1/3.5 isn't. You cannot install the basket with the dam gasket but keep the bakset to facilitate IP and IP timer removal and installation in the future.
- Attach new vacuum pump and dam gasket to front cover; I've only used metal gaskets and I install them dry; start each of the 6 10mm head bolts a few turns
- Tighten the 6 10mm head bolts a half turn at a time; I use the sequence for a 6-lug wheel
- I tighten by feel with my hand very close to the head of a ratchet; I'm guessing the torque spec to be no more than 20 lbft; continuing with the sequence for a 6-lug wheel



- The rest is the reverse of removal

Sixto
87 300D^2