Why do I have oil in my radiator resevoir, mazda rf diesel van??

Question

My woes continue with this van. After a new radiator and all been pressure tested, today it is obvious that there is oil getting into the water and coolant, does this mean a new cylinder head gasket is required??

Thanks for all the advice. I recently had the head pressure tested (last week) and it was fine. The oil in the water looks like new oil, it is not white and sludgy - also there is no sign of any water in under the oil filler cap

Answer 1

There is only ONE way for oil to get into the coolant system and that is through a leak somewhere in the engine. Now, the leak could, and usually is, caused by a leaking head gasket. You should have the engine checked both while hot and cold. Modern alloys used in todays engine expand and contract much more than old steel and cast iron engines used to and what you may have is a leak that is forming under cold engine conditions. This is more and more common and it is also one of the main reason auto manufacturers are adding "Stop Leak" products to their engines at the time of manufacture.

If you do not have a gasket problem then almost certainly there is a crack in the the coolant system wall. These can open under the pressure increases caused by normal acceleration and may be misssed by a mechanic doing a "static" cylinde pressure test.

Good luck, these types of issues in modern engines usually have bad outcomes. It is the trade off between, modern light weight materials used in these engines. When they are running correctly they are great, light, fuel efficient, the problem is they are not able to take much abuse and if something goes wrong the results are usually catastrophic.

Answer 2

You may be "lucky" and its only the gasket, but I would bet either block or head cracked, or certainly distorted. that means a skim, reshimming the valves, and new head gasket, all accompanied by a heavy dose of prayers and keeping your bits crossed!
With a diesel the compression ratio is about 23:1 whereas the rad is only about 10psi. The extreme pressure generated by the compression is forcing oil into the water galleries.
What were your previous woes? They may have a bearing on the problem.
Frankly, I would bung some bars leaks in and get shot of the wagon to a dealer!

Answer 3

Check; With the Engine/Radiator Cool Remove the radiator Cap, Is there Oil in the Radiator? Start the engine with the radiator Cap Off, after 30 Seconds, Do you Smell Exhaust in the Radiator? "Yes" Head Gasket. "No" Some May be Dumping oil in you Overflow Tank as a "Joke?"

Answer 4

Many of these have an oil cooler.
These sometimes will leak oil into the radiator.
If this is the case they will also leak coolant into the oil.
Check your oil for milky colour.
If you have recently overheated it, it is probably the head gasket.
Not to much for parts, but labour could get high.

Answer 5

if it looks like white chocolate moose then your head gaskets gone. Have a look at the filler cap for tell tale signs.

Answer 6

You said it.

Chances are all that work was, may not have been needed, coolant was going out the tail pipe now oil is coming in to the radiator.

Answer 7

check the oil cooler usually when they go bad you wont get coolant in the oil because you oil pressure is greater than radiator pressure

Answer 8

start her up from cold and look in the water, if there is turbulence in the water...then ..it sounds like the head gasket..if not..l would just keep an eye on it...and the mobile topped up...just in case

Answer 9

Since you say it is diesel it might be the copper tubes in the head that the injectors fit into some of them can be changed with out removing the head.

Answer 10

The head gasket has gone or the block is cracked!