2.4 head change!

[steve001]

Hi everyone,

Having recently got a 1990 2.4 Surf, it has been running well. Recently I heard some gurgling coming from the engine after I turned her off; on inspection I found oil in the coolant overflow and in the coolant filler pipe.

Without any further investigation, I'm assuming the head has gone! Is it a difficult job to replace the head yourself?

I do my own servicing and repairs but I have never attempted taking off and replacing a cylinder head. Would I be biting off more than I can chew?

Many thanks,

Steve

[Canadian_Hilux]

If the head hasn't already been done then you may as well do it. It's a 2.4 the factory cylinder head will inevitably crack. FYI it sounds like cross contamination of fluids is pretty rare due to where the engine cracks. If theres oil in your coolant check to see if you have any oil contaminated hoses or it could be the ATF cooler leaking tranny fluid into your coolant system

[steve001]

Thanks for the response.

Just a quick update.

There is no sign of coolant in the oil, no sign of ATF in the coolant - it has turned the coolant black.

I have checked the oil filter - that is secure and there does not appear to be any leak from the oil cooler.

I have rinsed out and cleaned the header tank and cleaned out the gunk from the filler cap. All the levels are okay. I have noticed that some pipes under the throttle housing that lead back into the cooling system, appear to have some oily fluid on them. I don't know what would be leaking around the throttle housing. Could this be causing the problem?

[TonyN]

When the head cracks it dosn't normally mix oil with the coolant, I've never seen one do this, it just pressurises the coolant and fills the expansion tank, I'd start with the oil cooler, it is behind the cover the oil filter screws to, and you can't see it without removing the cover.

It won't take much oil to make a mess of the coolant, so dosn't have to be much of a leak.

It could be the head gasket failed, but I've never seen one.

[steve001]

Thanks Tony,

What would I be looking for?

Would it be the oil cooler gaskets or the oil cooler itself that is actually knackered causing a possible leak?

Many thanks

[TonyN]

Its normally the gaskets, I've found bolts missing in the past, the turbo support bracket goes to one of the fixing bolts, often people leave it off cos its hard to reach and don't realise the bolt does another job too.

Its hard to describe without pics, there are 2 bolts each end of the cooler, the heads are visible on the outside of the cooler cover, each side of the oil filter. but you have to remove the whole cover, then flip it over and you see the cooler on the inside where it sits in a coolant chamber.

Its kinda tricky, but easier than taking the head off. And its so unusual for oil contamination to be caused by the head I thought I'd mention it.

[steve001]

Thanks Tony, I'll have another look tomorrow.

The truck itself is running as good as it ever has, so I think that strengthens the case for the head being okay (for now...).

I can't see any other possible leaks whilst I have been giving it a quick going over although it is due a service so I will have a chance to look with a fine tooth-comb!