Replacing the distributor cap and rotor on a 92 945T with the rear mounted distributor.

When removing the old cap I note that the distributor can rotate a few degrees each way. I thought on this car that the distributor was fixed with timing controlled by the computer.

Am I missing a couple of bolts that go through the flanges on the alloy base that the cap goes on?

If so what size are they???

Don't guess.....Get your timing set to factory specs. Your distributor has a hall sensor the you have to set the distributor timing. Some system use a flywheel sensor which needs no timing set. You should have a sticker inside the engine compartment. .I brought a New total replacement distributor $50. Save me from total rebuild of my old oily one.

The later 240s, 740s and 940s (89/90-on) either have LH 2.4 or LH 3.4 and EZK-116 or Rex-Regina (leastwise in the North American market). These systems use a crank position sensor (CPS) located on top of the bell housing to sense the flywheel and determine rpm rather than using a Hall Effect sensor in the distributor as in the earlier ignition systems such as EZK-117.

Alignment of the screws in the elongated slots in the rear cam mounted distributor caps should not be critical; The timing is adaptive and decided by the ignition controller based on rpm and engine load. As others note, matching the original orientation of the screws in the slots or just using the mid-point should suffice. Note that only 700s and 900s could have these rear cam mounted distributors. 240s always had side mounted distributors driven off the intermediate shaft due to firewall clearance limitations. Those caps align to a fixed notch and are held by clips.

If there’s a special procedure that Volvo uses to more properly align the rear distributor caps that I don’t know about then hopefully someone will post. Not many of us still have timing lights and know how to use them, let alone a decent dwell tach. I can’t remember the last time I used mine, if they even still work.

Now as for the rear mounted distributors themselves, I vaguely recall they also have slots for the screws, but something in the back of my mind says that one screw was not in a slot. Either way, it never hurts to scratch a mark for the top screw before removal.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

There is a plastic piece that goes on 1 of the distributor mounting bolts. it locks the distributor in place, if its missing, you can install the distributor, and set it to where the mounting bolts left their marks on the distributor housing.

Thanks, I set it to a nomimaly centered position and it seems to run fine.