Oil from distributor

[tmsmini]

I have had two engines that have developed an oil leak from the distributor. One is a current runner that is set to be replaced, but I still cannot figure it out.
The oil is not coming from the distributor drive shaft hole but actually from the inside. Oil seems to work its way up inside and then out to create a drip that goes down to the starter. Originally I thought it was the thin O ring for the distributor, but the oil actually comes from the curve at the bottom of the body. The distributor was rebuilt by Advanced Distributors about a year ago.

It is not a serious leak, but more of a why is it doing that...

[John Gervais]

Sounds a bit weird, is it an 'unlimited supply' of sump oil that's leaking or could it just be a bit of excess from the woolen pad at the top of the shaft that's dripping down and being evacuated via the drain hole?

If I over-oil the shaft/pad under the rotor, I get the same thing.

[tmsmini]

It seems to be unlimited as when I clean it all up it returns.
I thought maybe the oil pressure gauge line was 'squirting" a mist in that direction, but that is not the case.
I will try to get some pictures this weekend.

[tmsmini]

A neighbor came by and suggested the internal seal on the drive shaft is probably bad.
Anyone have an exploded view of a Lucas 45D?
I got some pictures, but they need to be resized.

[John Gervais]

To the best of my memory and general knowledge, there are no internal seals in the 45D distributors, only the external O-ring.

[tmsmini]

The only picture iIcan find is on Somerford mini and the detail is not great.
I need to pull out an old manual to see if it has anything.

[John Gervais]

Here's Sommerford Minis electrical .pdf library - it has a better image.   77.gif  Check out .pdf #6.

pdf-catalogues

I've had several of my own 45D4 units apart, and don't believe I've ever seen an O-ring other than the 513682A fitted to the drive spindle. 


There is a larger O-ring (p/n 13h2792) under the distributor housing, see item # 35 in the attached image.

13H2792

Perhaps this is the culprit?

[John Gervais]

I was just looking at the AKD3509 microfiche ignition images, (nerd), and although they're not 45D, rather 23D & 25D (but essentially the same principle, though less reliable (Moss Motoring Article -2006)) and there doesn't appear to be any internal O-rings. 

In the attached images, I've omitted the cover sheet.

[MiniDave]

The only time I've seen excessive oil in the dist is when the shaft bushings are worn too far - if you look at the pic above you can see a spiral groove in the lower part of the shaft, this is designed to direct the excess oil back down into the sump. If the shaft bushings are worn this won't be effective.

I got nuttin else...... ::)

[tmsmini]

My mistake, too many cars and too many distributors. This one is actually a 59D on this car. Early A+ engine.

[John Gervais]

The 59D should be essentially the same as 45D - heck they use many of the same components, I think the only real difference is the baseplate for the contact breaker points non-sliding red vs. sliding blue.

You're sure the oil is coming from the dizzy's drain hole and not creeping past the housing O-ring that's mounted to the block?

[MiniDave]

I can't think of anyway the oil could get inside the dist coming past that o-ring......it's not like that area has oil pressure to it. Whatever comes up there is thrown by the crank/rods and such.....

[John Gervais]

I agree.  I would think that the shaft would have to be extremely sloppy for a significant amount of oil to get past the housing, the 2 O-rings and accumulate in a puddle beneath the weights. 

I have been known to over-oil the shaft when I service my distributor; soak the felt pad with oil and give a little extra drop or three on the shaft under the felt pad, give a drop or two on and under the weights (where they drag on the plate with the pins).  This amount of oil will get flung about and evacuate by dripping from the drain hole.

I had a 45D re-bushed/rebuilt by The Distributor Doctor in the UK where he installs a full-length bush for the shaft to run in.  It was amazing how snug/solid it felt to the hand and I'll tell you, the timing is rock-steady.  Recommended.   4.gif

[tmsmini]

Let me see how these attachments come through.
You can see the drop on the bottom of the body pretty clearly and you can see the shiny reflection in the oil on the inside.

I am not sure where else the oil could be coming from.

[John Gervais]

Nice pictures, and I suspect it wasn't easy to get in there to take them - thanks for that.

You know what, though, I've been thinking about this quite a bit - since it's happening with both rebuilt distributors, how about sopping the small puddle inside the dizzy up with a Q-tip and see how it goes. 

I'm really leaning towards that it was over-oiled either upon assembly or when you put it into service.  Those 2 or three drops under the wool, combined with any used on the shaft and weights during re-assembly could really seem like a lot when they get warmed up, flung about, pooled and dripping out.

[tmsmini]

I need to do maintenance, so yes a clean start with a re-time is in order.
Jeff thought it is most likely crankcase pressure. On the 1098, I would have agreed as it had a lot of miles on it. This 1275 A+ probably has some miles on it as well. The block is pretty well vented. It is an early A+ engine with the flywheel housing vent, a vent from the mechanical fuel pump location and the valve cover to air cleaner.
The engine came with the car so I really don't know how many miles it has on it.

I have an engine ready to go in. I just need the time to install and it will be using a DIS. Mean while my wife can drive it to work.