Thread: How to Remove Vac Advance Unit on V8 D1

Originally Posted by Traco

My 1995 3.9 is idling rough and breaking down under high loads - conditions when the inlet vacuum is highest.

Took the cap of the distributor. I think the diaphram in my vacuum advance is shot. Sucked on the tube but the baseplate in the dissy does not move.

Apart frpm taking out the screws on the side of the dissy that hold the vac unit on, is there anything else I need to unscrew in the distributor? How does the arm that come out of the vac advance attach to the base plate?

Anyone know of a good source for replacement vac units?

The hole in the end of the shaft from the Vacuum canister simply slides over a pin on the bottom of the base plate, the spring tension on the vacuum canister diagphram keeps the shaft horizontal. You realy need to remove the rotor button, which can be extremely tight, dont prise against the Flash Sheild (plastic cover) as it will crack very easily, remove the flash sheild and position the canister in place, without screws and apply a small pressure to the shaft, downwards and locate the Pin under the base plate and release downward pressure so that hole in end of arm locates over pin. It's a bit fiddly as you cannot see the pin so it's a trial and error thing, but it's not too hard, bit long wided for a simple job though, Regards Frank.

P.S. British 4WD Imports P/L 03 9728 8046, about $128 inc. GST