The V8 Owners Forum -

My Landy has just been in for some work and the new flame trap was too full of gauze so pressure was building up and the same pool of oil form the distributor. Mechanic said if there was too much pressure the oil would exit from the bolt by the dizzy first. Probably not helpful but just check al the breather pipes are clear and not blocked - simple and cheap check.

DEVONMAN wrote:What about the joint between the timing cover and the block at the very top. The last picture shows stains running down from that area.

I was thinking the same mate!!

Darkspeed wrote:Try a bit of PTFE tape around the bolt threads.

Always worth a shot eh mate.

mgbv8 wrote:

Darkspeed wrote:Try a bit of PTFE tape around the bolt threads.

Always worth a shot eh mate.

Its either that or wipe some Hylomar blue on the threads or a stud with some gas seal.

Negative or lowest crankcase pressure is generated when the engine is at idle or when decelerating at speed.

If the engine is worn and the rings are letting by then only slight loads can create crankcase pressure if the breathers are too small.

I guess you don't have any means of logging or measuring the crankcase pressure. So there is one possible thing you could try. Please don't laugh guys!! I've done this many times on all sorts of equipment over the years.....If one of your breathers has a connection that can have a condom slipped over it so it can be taped on to seal it then fit one. use the strongest condom you can find or even a cheap balloon. Condoms are best because they are more sensitive to air pressure changes. Let the engine idle and see what the condom does?? Rev the engine several times to see what the condom does. If you rev the engine and there is sufficient blow by to inflate the condom in any way with the engine NOT under load on the road (as the engine is stationary) Your breather system is too small or your rings are letting by.

This is one of those little annoying leaks that can take an age to locate.

So you have some options with regards to finding the reason / source of the leak.

As said above:
Clean it all up. Remove the stud and use PTFE or even an oil resistant thread sealer on the stud to rule out the possibility of oil for some reason finding its way back up the thread. Check the stud hole for any signs of cracks in the threads.

Make sure that you are happy with the seal on the dissy body to the timing cover.

With regards to crankcase pressure!! Can you show us what breathers you are using Pitschi !

If you have breathers that are sufficient in size they will be able to let vapour pressure out and also allow the engine to draw filtered air back in as required. What I'm trying to say is that if your breathers are big enough you will not generate any excess positive pressure in the crankcase to force a leak like this. The Condom test will give you some idea.

I have also used a spray on chalk to find subtle leaks like this. its the developer spray that we use on testing welds for any fissures etc.
if you remove al the oil and clean the area spotlessly with brake cleaner or similar until the whole leak area is bone dry. You can spray the chalk on which will stick to all surfaces. You could then go for a quick drive and look at the chalk coating. This may well give you an indication of the leak source.


I reckon if I had your car in my workshop for a Saturday or Sinday we could bottom this problem out mate.

Perry

Thanks for all the input.

I have 4 breathers on the valve covers. The dizzy stud is sealed with Loctite.

Clean it up and put a bead of silicone around the area and see if it fills up or or the oil fills up around it. - Simple really - either its not sealed or its not the leak. Personally I would be looking for cracks or leaks elsewhere,

Okay gents,

After try&error I think the problem with the dizzy oil leak is solved. Thought that the little but permanent oil puddle under the dizzy stump came from the the bolt hole from the clamp or the O-ring because of too much pressure. Disconnected my additional oil feed pipe for the dizzy, still leaking. Changed the bolt to a stud and renewed the O-ring twice, still leaking. Was sure that the evacuation system (tubes from the breathers to the exhausts to produce vacuum) would be the BIG help to minimize pressure, still leaking. Renewed the dizzy O-ring again, a bit thicker and just fitting in, still leaking. Removed the dizzy again (I don't know how many times) and recognized oil under the cap!!
After removing the black plastic cover inside the dizzy and after additional inspection I could see a 2 mm high oil puddle at the bottom of the dizzy body!
The body has two small holes at the bottom. The Rover dizzy sits at an angle as anybody knows. Not vertical as a Ford or Chevy. One of the hole is at the lower position of the dizzy body when mounted. The addional oil feed for the dizzy is great to minimze the gear wear. But the aditional oil on the gears will cause oil inside the dizzy along the spindle too and that is turning to the top aka the body. When the oil is on a certain level in the casting it will drop through the bottom hole of the casting and hit the timing cover at the area where the clamp sits.

I disconnected the feed pipe again and made a 5 miles test drive yesterday. No oil anywhere

I hope that this problem is solved but that will show a longer run.

Well I sounds like you have found the cause.

Just a few comments.

Could it be that the seal below the advance weights is iffy.
Is there any side play of the shaft?
Is the small hole half way down the dizzy body clear?
There are oil grooves in the shaft. Are they clear?

Maybe your extra oil feed could be directed at the cogs differently.

Could it be that the seal below the advance weights is iffy. Don't know
Is there any side play of the shaft? Yes, but there is always a little play, isn't it?
Is the small hole half way down the dizzy body clear? Yes ist is
There are oil grooves in the shaft. Are they clear? Don't know, brand new one

Well,

After a 30 miles drive, new oil puddle

It drives me crazy but I'll find a solution.

Devonman, you got it!

After mounting the second time a brand new dizzy, the problem is solved

The 360 miles trip to SPA proofed that. The other "old" dizzy, that was laying on the shelf for a few years had inside a weak seal that allowed the oil to go up the spindle to the dizzy body and drops out of one of the holes directly on top of the dizzy clamp.

Cheers
Pitschi

Don't think there are any internal seals - just a thread on the shaft to push oil down. Of course if the bearings were worn, more oil could get past them.

DaveEFI wrote:Don't think there are any internal seals - just a thread on the shaft to push oil down. Of course if the bearings were worn, more oil could get past them.

There is a seal of sorts made of plastic below the advance weights, It's shaped also to act as a thrust washer and limit end play in combination with the shim at the drive end.

Agreed that a worn shaft / housing will soon oversize the hole in the plastic and allow oil to get up into the top of the dizzy

When I was locking up my dizzy weights a few years ago I was over enthusiastic with the welder and melted the plastic item below the weights. Lesson learnt !!!

If you go EDIS, etc, it's common to cut down a dizzy to a stumpy, just to drive the oil pump. Many of these don't have anything to stop the shaft just pulling out, so no plastic thingie to the top.