Advice please - ZD30 sump full of coolant.

[mickn]

Hi guys,

Haven't posted on here for a while because things were going OK after I replaced the ZD30's injector pump, injectors and glow plugs....

Anyway, I'm after some advice. The engine has now done just over 200k. It has been serviced regularly but recently started using coolant. I was able to track down some minor leaks around hoses but today checked the dipstick and found the oil is contaminated by coolant. The dipstick comes out covered in goopy grey crap.

I imagine I have a cracked head which is allowing coolant into the coolant passages somewhere, but the amazing part in that the engine runs fine and there is not a trace of bubbles in the radiator. I have noticed a loss only from the expansion tank, never from the radiator itself.

Bearing in mind I have invested significantly in this vehicle already what do you guys recommend? Replace head/replace engine with rebuilt/replace with crate motor?


Regards,

mickn

[johno90]

Heads and head gaskets can crack in many different spots doesnt always mean combustion pressure in coolant.
crack from coolant to oil return ports= exactly what you have.
you can also crack heads:
Oil into Coolant
Coolant into oil
Oil into pistons
pistons into oil
coolant into pistons
pistons into coolant
coolant to outside of block
oil to outside of block

Can happen any type like that or a combination :)
But I am sorry its time to play the ZD30 game, do you dare roll the dice and see where it leads :P

[johno90]

On these systems the expansion tank can be thought of as just part of the radiator. Id suggest rebuild or crate either way. Or look at another engine all together. No matter what option your going to be in it for no less then 6k. You could always just crack test the head and through a gasket on it and see what happens.....

[happygu]

It looks like you would need to pull it down before knowing what is best .....

If the pistons and bores are OK, then replace head .... if there is more damage then think about a complete replacement.

[mickn]

I always knew the news wouldn't be good.....is there a chance the oil cooler is allowing coolant into the system, rather than it coming from the combustion side? I'm looking at all possibilities here.

[johno90]

Yea thats quite possible :)