Have a slightly odd issue where cold weather causes water to appear in the engine oil. This only happens with the ebarspacher heater being tripped on. All last summer it was fine - never used a drop but this winter, the water level will drop from max to min in the expansion bottle in a couple of days and I get a very high creamy oil level on the dipstick - not good at all!
This always coincides with the eberspacher running at warm up.
I see that the eberspacher has no oil feed so that's not the issue. Sometimes it'll bang when it starts and I get a lot of smoke from it sometimes - more than likely has never been serviced. My guess is that when it's heating the water it pressurises the coolant system higher than the engine ever will and this pressure is forcing past a seal - inlet manifold seals have been mentioned.
Any ideas?
I'm sure there is no possibility of coolant in the oil from the inlet manifold, since you can replace the manifold without touching the cooling system. The only point for cross contamination like Brian mentioned, is the oil cooling at the filter housing. If not there then you have a head gasket problem, which means the engine out. I don't think the Eberspascher has anything to do with this coolant in oil problem and is a separate issue.
Roy