Chris Bebs

How big of a job is it to replace the exhaust manifold gaskets on a mk2 2.5 v6????

DanW@FastFord

iTrader: (1)

Quite a big job. Not one I'd suggest attempting unless you're a competent DIYer. Make very sure it is that that's blowing (I presume you've got the 'dreaded tick) as I've known people change them and the 'tick' remains.

liam-rst

iTrader: (1)

As Dan said, front is tricky and rear is an absolute bastard, if its ticking fingers crossed its not your head gasket lol

Chris Bebs

Yea I've got the tick and its pissing me off I've tryd hydrolic lifter cleaner, engine flush and oil change also took it to a garage and had new fan belt wheels fitted as they thought it was bearings ticking but no it still remains!!! I had it on some ramps weekend and the rear manifold is leakin a little bit of oil which to me is the problem and creating the tick, apparently they can come lose and just need tightening up but I think replacing the would be better! It's defiantly not the head gasket 100%

DanW@FastFord

iTrader: (1)

How do you know, have you had a compression test?

Chris Bebs

When the head gose you lose water/oil and also power and none of the have accurred apart from the oil which is coming from the manifold

DanW@FastFord

iTrader: (1)

Not on the V6. There's a weak point on the gasket which vents to atmosphere. There will be no water, or oil loss, and a barely perceptible loss of power. It will cause a very similar sound to the exhaust manifold blowing, but can go on for miles without getting worse, or causing an issue.

Hence why I said be very sure it's the exhaust manifold before attempting a replacement. I'd want to be feeling the gas actually coming out of it before I considered pulling the engine apart.

Chris Bebs

I've bin told on the v6 engines when the head gaskets gone your water will bubble the odd bubble is normal but when it bubbles constantly then that's the air escaping

DanW@FastFord

iTrader: (1)

The gasket blows in such a way that it doesn't affect the oil, or water ways, so 'normal' diagnosis isn't relevant. When I broke my ST200 I took the heads off to check as I'd had the 'tick' for months. Sure enough there was a tell tale 'scorch mark' where the gasket had gone.

Not saying that's what you've got - but just google 'Mondeo V6 head gasket' and you can see the amount of people who have had the issue.

Chris Bebs

Where about on the head? Is this the weak point?

DanW@FastFord

iTrader: (1)

Here...



and here...



There are several weak spots, but this is the most common.

I'll also add that the exhaust gasket had blown on mine, and that it does cure 'some' people's cars. Just be sure.

liam-rst

iTrader: (1)

Best thing to do would be to get a compression test done and go from there mate, listen to Dan he knows his shit of if not im sure fiddy would be a great source of info if you need

Chris Bebs

Thanks for your help

DanW@FastFord

iTrader: (1)

Yup, a compression test would be the cheapest way to rule out the HG.

thegfb

When the HG went on my ST24, I only noticed because I was under the car looking at the state of the manifold studs in preparation for switching them over to headers.

On the rear bank near to cylinder 3 I saw a trail of oil coming down the block which was definitely coming from the join between the head and the block (not high enough for the manifold). I checked the schematics and did a bit of research, and sure enough there is an oilway and weak gasket point right there.

I took it for a 400 mile round trip without problems then decided I'd used all my luck up and fixed the HG myself, I figured it would be much easier to fit the new headers to the heads with them off the car (this was a VERY good idea now I've done it since there was one stud on each head that was proper rusted in and needed heat and a lot of room to turn it out which would have been near impossible with the heads on the car still). When I got the heads off the scorching to the head and damage to the gasket was evident right where I thought it would be.

I lost no water and no excess oil (though it was leaking, it was very slow and not noticeable), and power remained normal. I didn't bother compression testing it because I wasn't in denial, I knew the HG had gone