I have been a mechanic for 30+ years and this is a new one to me. Wanted to use a timing lite on my motor for the first time in 3 years. The waterpump lower hose outlet always covered my marks, so I spent the weekend changing to a later pump with the outlet on the passenger side and making new mounting brackets for the power steering and alternator. Test drove and all is fine. This morning I decide to check the timing with a light to see where it was set with my ear. Timing was at 12 * before TDC, (not a bad ear...LOL). At the same time I discovered my vac advance unit had a hole in the diaphram and not working at all. Just happened to have another one on the shelf. Installed it and checked out the rest of the dist. and ignition before installing in car. Started the car and checked with light and baseline install was at about 17* with out vac. Car seemed to idle a little rough. NOW here is where it gets weird! Set it back to about 12* and plugged in the vac and timing umped to about 20* and on accell acted slow. While watching the timing marks they are jumping all over the place like a bad chain or dist shaft. All are new and show no play. Even pulled dist and checked the dist /oil pump drive gear for play ...all is good. Only play I found was in the way rotor fit the shaft and tightened that up. Now to make the engine run good and accel like it should I set by ear again and checked with light ... base timing was about 25-27 * and total was over 50* (when you could see the jumping marks ) At these settings it runs like a bat out of hell and doesn't ping or buck against the starter.
Ok , my question is what the hell changed so drastically and where is my play in the timing?
Let me add that if I slow the timing down to my original settings the car wants to die and is slow to accellerate. I never have run into this before and it doesn't make sense. I even threw in a completely different dist with the same results. I "ain't " gonna run it this way so throw me some ideas !
