1998 C70 2.5 Auto - petrol in oilpan

[cgimec]

hi all,

a week ago I found something like coffee milk on the oil dipstick. I assumed it was condensation, as the car wasn't driven on long distances for a while. I still had oil on the dipstick. today I took the car for a 60 miles journey. I assumed if there was water, it would evaporate and the leftovers would be oil. well, the theory is wright, but I assumed wrong. it's not water and now I have cappuccino and no oil it smells like exhaust gases, so it's petrol mixed with oil. nice color, though. to keep her alive and not to damage anything more than already is, I'll schedule an oil change with a thicker oil and I'll add some additives. this will buy me some time to see if the issue is real or it was just too much water.
the car starts and drives without any problem. no blue smoke, no white smoke. it pulls and accelerates as usual. no errors.

it could be a faulty injector, a faulty head gasket but the coolant level is normal (this could be bad but not as bad as the next two faults), piston rings (engine rebuilt, here I come) or a cracked block.

did I mention the car has only 72K on it, always serviced at regular intervals by volvo dealership? I've done 13K with her without any major problems.

now, what options do I have? I'll have the compression and the injectors tested, but is it worth an engine rebuild? if it's the head gasket, then it could be 50/50 with the cracked block. any other possible faults, like in the old good carburetor days?

thanks.

[DunkinBiskits]

Hi,
are you sure its petrol? if its 2.5 itll be 83mm bore (weak liners) so youd be right to suspect to block, but id be more inclined to blame a cracked liner or a failed Head Gasket for funny coloured oil than it being fuel in the oil.

The only time ive seen fuel in oil is when on Direct Injection engines (VAG ****e ) and an O ring fails in the high pressure fuel pump thats got an oil supply from oil pump and it squirks petrol into the lubricant.

These cars arent direct injection though, and sticky injectors arent too common either on these Boschs tbh.

pull your plugs to see if you have any that are 'shiny'

this is a sign of coolant ingress into the cylinder as the steam is cleaning the hydrocarbons off them.

Compression test and a cooling system leakdown test will be helpful, also an endoscope down a spark plug hole wouldnt hurt.

If it is a cracked liner you can shim the expansion gap between them and in 9/10 cases this closes up the crack and is good for the forseeable future.

[cgimec]

Hi DunkinBiskits, thanks for the input. I'm not 100% sure it's petrol, but smells like it. I'll check tomorrow with the engine cold. Unfortunately I have no tools to test more than the spark plugs, which is a very good idea.

[cgimec]

good news: all the checks done, nothing found. flushed the oil and there' more oil than water/fuel so we agreed the milkiness came from too much moisture. so I'll have to drive it more
I also changed the battery.