'88 305 LB9 TPI Motor 96,000 miles

Before I pulled the distributor, the distributor cap was removed and I took notice of the rotor orientation. It pointed to the little "W" symbol on top of the master cylinder cover. To me that was sufficient as a target of rotor orientation in my opinion. At this point I thought it would be easy to reinstall after that. Boy was I wrong!

I feel like a victim now. Just for laughs I attempted to reinsert the distributor ( 10 times ) and the rotor points to a different location when it's totally flush with the intake manifold. Ok...so there is the number of teeth I have to play with to get to the sweet spot.

My question: How do I find the sweet spot so the distributor sits flush and meshes with the camshafts gear originally?

Points of matter:
1- The 305 motor has not been spun or bumped since distributor removal therefore the oil pump tab/gear hasn't moved.

2- Would it be easier just to find TDC? I'm a complete novice on that. A search on YouTube clarifies the procedure and I'm willing to go that route as a last case scenario. If TDC is to be found, does the 305 have to be re-timed? I do not have a timing gun yet in my possession.

3- I have yet to look down into the distributor hole to take note of the oil pump tab for its orientation. I have read that I can move that with a long flat bladed screwdriver. Should I move it? What will I expect if I mess with that? I tried turning it when the distributor was in and it felt locked solid, normal I concluded. I assume the oil pump gear is meshed with the cam gear, correct?

4- Rebuild the old distributor? Magnetic pickup feels fine but that electrical part I see attatched to it looks like it should be replaced since its 21 yrs old. I just want the 305 to run again.

5 - If I find the original sweet spot, I assume I do not have to do engine timing since it ran very good?

This is very deceptive and I'm in panic mode here lol. Would like feedback as I'm heading off to work. Looking forward to your replies, links to solutions, etc. Thanks In Advance !!!

 

i feel for you. I am going thru the same problem. I went thru the whole procedure with finding tdc and pointed the rotor at the #1 cylinder, but my car still will not start. I am still looking for the problem. anyway I moved the oil pump shaft with long screwdriver with no problem and it took me about 12 tries of putting in the dist to get it to point to #1 cylinder. goodluck and maybe some of the answers you get might help me.

 

1) If that were the case, then the dist would sit flush when pointing where it originally was. As you pull or install the dist, the rotor turns and this causes the oil pump shaft to turn with it. Just use a screwdriver to reposition it until things go together the way you want.

2) You would need to find TDC on the firing stroke. That means you align the timing mark on the balancer with the tab on the cycle that is causing air to whoosh out the #1 plug hole. You can do this, but if your sure on where it should point and you haven't cranked the engine at all you should be able to just use a screwdrive to align slot in the oil pump driveshaft.

3) No, the oil pump gear is driven via a short driveshaft that engages with the dist. No dist installed, no oil pump drive possible.

4) Your choice, but a new dist isn't much more.

5) Your timing is based upon the outer part (cap/body) of the dist and its position, so yeah you should put a light on it and check it. Before pulling mine, I made a mark on the base of the dist and the intake with a sharpee, that way I could put it back exactly where it was.

 

Been wrenching SBC's (since '66) almost as long as SBC's have existed.
And on of the first epiphanies I experienced was how to re-set
the distributors.

As stated above, the source of the problem, is that as the dizzy is
lifted out, the shaft rotates as it disengages first from the oil pump
drive shaft, then the cam drive gear. For this reason, marking the
INITIAL position of the rotor is not nearly as important as marking the
FINAL position, which unfortunately is neither as easy, or intuitively
obvious. Regardless, the likelihood of getting the shaft to rotate
back down into the exact position it left the oil pump is slim-to-none.

However, think about the problem a bit more. Obviously, the end
goal is to get the ign. timing properly set. The oil pump shaft will
come along for the ride.

SO...

Insert the dizzy, getting the rotor to finish as close as possible to TDC,
when aligned with the #1 contactor in the dist. cap.
(And remember, the crankshaft passes TDC TWICE during
a combustion cycle, so make sure its on the ign. portion.
Easy enough to accomplish if you have the rotor at #1,
and the crank at TDC, when you start disassembly.)
With asistance, or a remote starter switch, turn the engine over,
while holding the dizzy body. At some point the dizzy shaft will
align w/ the oil pump, & drop down into place -- works every time.
FINAL adjustment is made w/ timing light, according to specific
enging spec's. i.e. for EFI, different setting, while ECM is config'd
for ign. timing.

Good luck.

 

Here are some pics of my progress so far...follow along with quick newbie questions below.





1st pic - I worked my way past sunset. Labeling begins.
2nd pic - Early am disassembly begins. More labeling.
3rd pic - Looks like some major cleaning to do! How do I know if I have solid mechanical lifters or hydraulic roller lifters?
4th pic - (Bottom view of distributor shaft) This looks like a pin but unsure as there is a single hole on the side of the shaft, I'm wondering if this will shear off on me?

Bonus question: In the 2nd pic, those must be the token Centerbolt Valve Covers. I'm tempted to pull the valve covers off due to extra crud hiding under them I suspect. What is the size of the Torx bit I need to remove them? I thought I had all the tools a man can buy...

I removed the waterpump, radiator, electric fan assembly also. RockAuto sending me a replacement waterpump soon. RockAuto.com is a money saver fyi.

 

I skipped all of the replies. ---- and jump down here. Did you notice how the rotor turns backwards (counter clockwise) when you pull the dizzy out? It will rotate maybe about 15 to 20 degrees. Provided that the crank has not been turned, you need to start the rotor pointing in the direction that the dizzy was released,,, not where it was pointing when it was locked down. Also, get a flash light and look down the dizzy hole and check where the oil pump drive slot is. See if it looks like its in the right position for your marks.

 

nevasuma: You do not have to point the rotor to cylinder #1. For my car, when at TDC for #1, the rotor points toward #5 cylinder. You just have to recognize that the post in the dizzy that the rotor is at, is the #1 spark plug location. The spark wire coming off of that post must go the #1 spark plug.

 

These are all good replies. I do recall the distributor rotor turning counter- clockwise upon removal. I will play with that and post later.

I have a picture perfect day to work on the Z28!