1960s 69 DeVille - Cannot Get Distributor to Seat

[R Simone]

Well today was the day I'd been waiting for since pulling the engine last Fall.  Battery charged, engine set to TDC, everything ready to go, engine primed with break in oil, ready to turn the key... However, we could not get the distributor to seat.  We tried almost non-stop for four hours. We must have spun the distributor a hundred times over, we checked and tried different alignment of the oil pump drive dozens of times, we pulled the spark plugs and turned the engine by hand in the smallest of increments many times.  The distributor gear engages easily, but it just will not drop onto the oil pump drive.

There does seem to be some up/down play in the oil pump drive shaft that we thought might be messing us up. I "think" tightened up a bit each time after re-priming, but we tried that two or three times also - no dice.

I'm utterly deflated because we made no progress whatsoever and feel like I'm headed for summer #2 of no Cadillac.  The only thing we could think of was trying a different distributor just to try something different. I know the guy that damaged the engine had a heck of a time getting it out, though I see no damage anywhere on the teeth or shaft.  I'll wait to see if you guys have any advice, but if not I may just order a new (used) one... Ugh

[The Tassie Devil(le)]

I understand your frustrations.

Looking at the spiral gear on the Distributor, you wil notice that as the distributor descends, the shaft will turn.

If the Oil Pump Drive is not turned to match the amount of turning, the two will never line up.

You have to set the drive shaft ahead of where you think it has to be so that as the distributor goes downward, the meshing parts will align together.   The amount of "pre-turning" required is the vertical distance of the spiral gearing.    Does this make sense?

If you had oil pressure before, then the distributor was aligned, Or did you simply use a priming tool?

Lastly, I have come across the oil pump wanting to not stay at the place you put it after priming because there is an oil pressure resistance within the pump, and the shaft wants to "spring" back because of the oil pressure.   When this happens, I simply hold the priming tool for longer to let the pressure stabilise.

When you get it right, there is nothing like the satisfaction when the Distributor pops down.

Bruce.

[R Simone]

We built oil pressure with the priming tool only. I also noticed the shaft movement just a skosh after priming/ made sure we waited until stabilized. However, I did not account for that much "pre-turning" so maybe we just need to shift it counterclockwise a bit more while trying to install?

[TJ Hopland]

You should just have to make slight movements of the pump drive shaft and try dropping it again.  The bottom inside of the distributor gear is tapered isn't it?  It should be to account for slight slop in that shaft when its not supported. 

Are you sure you have #1 on the compression stroke?  Remember the timing mark aligns twice and only one time is the one you want the rotor pointing at the #1 terminal/wire. Finger over the spark plug hole to feel for air pushing out is the easiest way to tell with the valve covers on.  Also remember on this engine #1 is on the passenger side. 

[R Simone]

Honestly we kind of gave up on being TDC after we had so much trouble - thinking as long as we could get it to drop we could make whatever plug we want #1.  I know it's ideal, but would that have any bearing on getting the distributor to drop down?

[TJ Hopland]

Nope.  Really the only limitation is the vacuum canister running into something as you try to rotate it to get it in time but usually you can do the jump it one wire trick to get it.

I'm trying to remember is the drive on these a hex or a flat blade?  Is the distributor gear new?  I also don't remember can you just lift the pump drive shaft out on these?  What I'm getting at is what will be the easiest way to get those two pieces together to prove that they do actually fit together.

Has anyone got one of these engines apart or at least the distributor out can can get some sort of measurement how high that shaft should stick up?  I'm just wondering if somehow he has some wrong or bad parts that just don't go together.   

[Lexi]

Well today was the day I'd been waiting for since pulling the engine last Fall.  Battery charged, engine set to TDC, everything ready to go, engine primed with break in oil, ready to turn the key... However, we could not get the distributor to seat.  We tried almost non-stop for four hours. We must have spun the distributor a hundred times over, we checked and tried different alignment of the oil pump drive dozens of times, we pulled the spark plugs and turned the engine by hand in the smallest of increments many times.  The distributor gear engages easily, but it just will not drop onto the oil pump drive.

There does seem to be some up/down play in the oil pump drive shaft that we thought might be messing us up. I "think" tightened up a bit each time after re-priming, but we tried that two or three times also - no dice.

I'm utterly deflated because we made no progress whatsoever and feel like I'm headed for summer #2 of no Cadillac.  The only thing we could think of was trying a different distributor just to try something different. I know the guy that damaged the engine had a heck of a time getting it out, though I see no damage anywhere on the teeth or shaft.  I'll wait to see if you guys have any advice, but if not I may just order a new (used) one... Ugh

Not familiar with the '61 engine but if it is the same as my earlier Cad, the distributor fits down over a removable shaft that engages the oil pump as I recall. It may be possible to put this shaft in upside down. For what its worth have a look. Perhaps this part is incorrect as it got mixed up with another that does not fit properly??? Clay/Lexi

[Big Fins]

I don't remember if you can drop the oil pump and then place the drive up into the dizzy when it's in the correct position.

[R Simone]

From pictures online it looks as thought the oil pump end is hex, but the distributor end is slotted (no real way to mess that up).  I called an engine builder familiar with the 472 and he said he strongly advised against pulling the oil pump apart as it would be even worse getting it back together correctly, and many an engine had been lost that way.  I actually found a used distributor locally today so will be giving that a try this week.

[TJ Hopland]

I don't think there were different versions of the slot so I would not think there is much that could go wrong there.   Decide where you are gonna point the rotor, ideally pointing at something easy to reference and drop it in as far as it wants to go.  If it doesn't settle pull it.  Use a long screwdriver to slightly turn the oil pump shaft and try again starting with the rotor in the same position.  Repeat til it drops in. 

You want to always start with the rotor in the same spot so you are engaging the gear in the same spot.  If you don't start in the same spot you could just be chasing the position and with the slot there are only 2 spots it will drop vs 6 if it was a hex. Its like a USB jack, ya know it usually takes 5 different tries even though there are only 2 real options.

If you look at the pin in the gear vs rotor relationship and then where the rotor is pointing when it drops as far as it will go you should be able to get an idea roughly like with 90* of where the slot in the shaft should be pointing but even then you may have to make several slight moves.

I have never tried but if you have a borescope maybe you could see that junction through the fuel pump hole?   

[R Simone]

Got back from a ~ 2 week trip and gave it another try today and got absolutely nowhere...    

I got a donor distributor and we took the shaft out of it and it went in, but obviously has more "wiggle room" literally. The donor mic'd the same as my original, we tried TDC, not TDC, turning the distributor shaft, turning the oil pump shaft, turning the engine by hand, bumping the key (both with slight downward pressure) and didn't accomplish anything but knowing we now have fuel to the carb if/when I ever get the distributor in. We've now probably 8 hours of trying to get this in and I just can't see that we wouldn't have even had some dumb luck the couple hundred times we've tried. You can feel it engaging with/being pulled in by the cam gear, but doesn't seem like it will go further and then align onto the oil pump shaft. I'm going to look through the engine rebuild sheet tonight to see if they replaced the shaft with a different one? I'm just grasping at straws but don't see how it could be this difficult if all the parts are correct?

[TJ Hopland]

So the different distributor fits if you just stick the shaft and gear in?   

Are you following this process?

-Decide where you want the engine and where you want the rotor when you drop it  find or make some sort of marks so you can orient the rotor to the SAME position for every attempt.  Do not move the engine once you get it where you want it.

-Attempt to drop it in.  Rotor should move as it drops.  If it doesn't go pull it out use a screwdriver to rotate the oil shaft just slightly like no more than 1 O clock of a turn.  Try to drop it again and the important part is start with the rotor pointing in the exact same position as last time.   

[R Simone]

Yes, the sacrificial lamb distributor fits if you just stick the shaft and gear in.

I put it to TDC and rotor pointing towards #1 cylinder (and every over which cylinder), but it seemed way easier to keep the rotor pointed at #1 and pull the distributor barely out of the cam gear just enough to clear and then turn the distributor shaft incrementally vs pulling it all the way out and moving the oil pump shaft. I can definitely try it the other way if you think it will make a difference, or maybe that moves it just a bit less?

For half a second I thought about pulling the timing cover off etc. and trying to mate it up, but the thought of that made me sick since it's ready to fire expect for the distributor.

[TJ Hopland]

but it seemed way easier to keep the rotor pointed at #1 and pull the distributor barely out of the cam gear just enough to clear and then turn the distributor shaft incrementally vs pulling it all the way out and moving the oil pump shaft

The way you are doing it moving one tooth at a time you are making exact jumps and the pump may be sitting at a half tooth alignment which you will never hit by taking exact steps. If you just move the pump slightly you should eventually hit it.

#1 is usually over the dwell window on the cap and I believe its usually pointed more in the 3-5 range.  It really doesn't make a lot of difference as long as you can make everything reach and can access the dwell screw and the vacuum advance can doesn't run into anything.

[TJ Hopland]

And don't forget #1 is on the passenger side of this engine.

[Jeff Rosansky CLC #28373]

I typed this and it didn't post so apologies if it shows up twice.

Just thinking outloud here-----
Is it a gear engagement issue, or a problem with the block itself?
You said they had an issue getting the old distributor out. Did they beat it out, and in doing so, mess up the inner diameter of the mounting location? Maybe the distributor won't physically fit on the hole on the block because of a burr or something.
Just a thought, and good luck.

[TJ Hopland]

If there is a chance that is the problem maybe take apart the 'good' distributor and make sure the body will fully seat then try the shaft alone?

[R Simone]

Update:  I called an "old timer" I used to work with who has had countless really nice classic cars and always seemed to have the Midas Touch any time he worked on or dealt in them.  He stopped by and helped verify correct TDC & Stroke, took some measurements, and got it to where we had it a hundred times, but then suggested we give it just a few slight taps while he held it in place.  I gave it probably 5 or 6 gentle love taps with a hammer & screwdriver and it went right into place.

My buddy who is helping me was leery because he'd never hear of that before, but we cranked it and oil was sure enough flowing/no odd noises.

We couldn't start it because there's a vehicle behind it right now and it's upper 90's so my buddy didn't want to move cars around and lose all the AC in his shop, but we're ready to rock and roll in the next few days as soon as installs a few more parts on the vehicle in question and can easily move things around.

My cam was reground, but I'm not sure what they do with the gear if anything and we're not sure what the hang up was (gears not quite meshing or ?) and we are just a little bothered - anyone ever had to do this/reason for concern..?

[The Tassie Devil(le)]

With the regrinding of the cam, the Distributor Gear is not touched.

As for tapping it into place, there had to be some interference, but mentioning that it was hard to get out initially, means that there is something wrong down there.

One thing I would have done is to remove the distributor, and without moving anything (so it all goes back into place) I would be looking at any witness marks to see where the problems lay.

If it is a housing problem, that can be fixed, but anything else will need the engine to be stripped, and problems corrected.

Bruce.