Hello,

So the 850 has been going well now for quite some time and i've noticed this has started to happen, any ideas?



Whats the cause of the oil doing this, gasket or something worse?

Thank you in advance.

Check to see that the breathers you have on the motor are clean and working . Can you see where the oil is coming from that's below the head , does it look to be dribbling down the back of the head from the rocer cover gasket or does it look like it's from between the head and the block ?

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the breather just goes into the carby filter, the filter is about 6 months or less old.
I've just checked, its not dribbling down the back from the rocker cover. The rocker cover seal looks fine.

It kinda looks like its between the head and the block, it doesn't really run it looks like its weeping almost.

Thank you.

Are there any other breather's on the engine , preferably down the back under the carb ? Not much help if it is coming from between the block and head though . Give the motor a good degrease and watch it to see what happens . Also go for a good drive and stop from a 80 kph or so and check under the oil filler cap straight away to see if it's building up pressure and is full of oil .

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Could be a weeping head gasket. The problem with oil leaks evident on the engine number is they can have travelled from round the back of the head. Check the head gasket area at the back (ie on the other side of the head) as that is where the oil pressure goes through the head gasket. It can develop a large leak quite quickly if you don't catch it in time.

automatic rust control

bottom one is head gasket

Thanks everyone for the input (automatic rust control...ahaha, i like it).

I changed the oil / oil filter on the weekend, put some KMX as recommend by the ausmini's.

I tried your advice (sports850) under the cap was dry, i cleaned it up a couple of days ago and checked it again today, looks like its very slowly working its way out again.

Towards the back of the engine looks oily, i don't think its a leak though it just looks wet, but not dripping? It all appears to be on the right side of the engine (standing from the front).

I also checked the filter, it wasn't too flash. Its a ramflo filter. Whats the best way to clean them?

I can't see any other breathers though.

Thanks again.

There is a couple of things here.

Just about all mini heads warp over a period of time and it changes the tension on the head studs. The gasket is already fully compressed. Therefore the compression of the motor is forcing the oil seeping out under the head. The oil is getting into the combustion chamber past the rings. They may not be that worn but with a lot of air pressure in the sump/gearbox its adding to it.

To check - with the engine warm and running - take out the dip stick and see it its spitting noticable amounts of oil and fumes. If so, you have increased crankcase pressure and you need to do something about it.

The easiest way is locate a tappet cover plate with a breather outlet, fit that (wash it well in petrol first and replace the guaze with stainless steel scouring pad material) and plumb that into the original carby breather as well as the rocker cover one.

It all points towards an engine that is going to need rebuilding some time in the future.

Mike