ive got oil in my water but no water in my oil is this the head gasket?

Question

i dont know any history about the car it was left to me..... in this condition. is it poss that the head has been repaired but they never flushed out the coolant system? and whats the best way to flush out the coolant system? or can i do a test to see if it is the head gasket!! its a volvo s40 TD 98 manual gearbox. it is thick black sludge not a creamy colour on the lid of the exspansion bottle.

Answer 1

Its a good chance you have a blowen head gasket,not knowing what the car is it also could be a blowen upper intake/pletum gasket

Answer 2

Water is at higher pressure than oil, so you're probably OK. A good flush is the first step. And make sure it's oil. If someone put the wrong antifreeze in, the mixture can cause a nasty sludge to form. Oil usually doen't look like black sludge when it gets into the radiator.
You need a killer flush with cleaner. It's can be kind of hard to do without a lot of experience. There are tricks to making sure every nook and cranny are clean. You need to get the water perfectly clean and then flush again. Don't second guess the manual on antifreeze type or amount.

Answer 3

If it's black sludge that sounds like an additive. Many modern cars are cooled with a combination of water and an alcohol additive as this is more efficient. At worst this will be a breach in your radiator between the oil coolant section and the water coolant. The oil is fine enough to filter through but the water cannot get back as it's under no real pressure there. get the water filtered and replaced, if it re-appears you may need a new radiator, but block seal may well fix this.

Answer 4

It's certainly possible that there is residual oil in the coolant from a previous head gasket failure. Why not try a cooling system flush-out with one of the proprietary cooling system cleaners from Halfords or somewhere similar.

Refill the system with a 50/50 mix of antifreeze and soft water, and monitor what happens. A head gasket or cracked head or block willl soon makes itself noticed.

A garage can put a sniffer probe in the radiator to detect for leaking combustion gases, and sometimes a compression test is revealing. Both of these will cost more money than the flush and refill suggested earlier.

Answer 5

Black Sludge would tell me it's more of an additive then Oil. It's possible that there was a coolant leak at one point in time and they added a stop leak additive to it. I would flush the system and see if it comes back. If it comes back then look at it being a head gasket or bad seals. but I think it's is most likely it was an additive. Oil often does not look like black sludge in the radiator or over flow. It would look like chocolate milk.

Answer 6

A simpl head gasket test is to have a look at the inside of the oil filler cap. If its got a white pasty residue its meant to be a sign of water in the oil.

And there shouldn't be black sludge in the expansion tank!

Answer 7

First thing to check is oil cooler,This is normally located where the oil filter bolts on.Reason to check this first is that oil pressure is much higher than water pressure so oil fills coolant system quickly with little emulsification.If oil cooler is faulty replace & get a couple of tins of FORTIE COOLANT SYSTEM CLEANER.Try to get as much sludge as possible out to start with.

Answer 8

It's your head gasket or a valve seal failure, it does create a grey brown sludge in the rad though not a thick black one usually. You would need a compession check to truly see if had gone, or a radiator pressure tester to see if the rad pressure goes up abnormally.

Answer 9

It sounds like a head gasket fault. Oil is a complete nightmare to remove from the cooling system, and to be honest it's nigh on impossible.

Answer 10

yep,thats what it is.you need to change the head gasket,but if i were you,i would get the head shaved and pressured cleaned first,in case the head is warped.