Disco 2 TD5 head core plug behind manifold

Morning folks, my TD5 has sprung a coolant leak from the core plug on the head that sits semi obscured by the manifold.

Is there advice or guides for removing the manifold and changing/re-seating the plug?

many thanks

Ben

The allen key headed one?

If so its a kin arse, well mine was anyway, and removal may result in thread loss.

Manifold removal is a piece of psis

My old td5 leaked there for years, only leaked when it was cold and lost so little coolant I never bothered doing anything about it.

There are tales of people drilling the manifold in situ so you can get at the plug without touching the exhaust. Knowing how these things like to warp the manifolds I would be tempted to just bite the bullet and remove manifold, replace gasket etc

Stripping the threads worries me

TheMunster said:

My old td5 leaked there for years, only leaked when it was cold and lost so little coolant I never bothered doing anything about it.

There are tales of people drilling the manifold in situ so you can get at the plug without touching the exhaust. Knowing how these things like to warp the manifolds I would be tempted to just bite the bullet and remove manifold, replace gasket etc

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+1^
Having had the well-known nightmare of the warped manifold, i would say if yours has not warped then this might be the time to do a bit of preventative work while you are there.
When mine warped it pinged out two or three studs and one was snapped off below the surface of the head.
So if you manage to get yours off without stripping a thread you'll be very lucky.
Only sure way of doing that would be to split all the nuts!
Once off and reground flat, I was forced to replace a couple of the studs with bigger ones, i.e had to drill out and cut new threads, then fit bigger studs. This is very typical of what others have had to do.
I then ensured it couldn't do any more damage by drilling the holes in the manifold (and gaskets) out a bit. cylinders 2 and 4 by a mm and 1 and 5 by 2mm, to give the manifold a bit of "wiggle room". Other people have also sawn through the webbing. Purists/professionals would helicoil the damaged holes.
So you could maybe, if yours hasn't warped yet, saw through the webs, and then remove the web where the core plug is and hope to get it out without damaging the thread. But I seriously wonder why anyone would ever want to remove that core plug except if it rusted through. A pro on here or someone with more knowledge than me, will tell us! But everything i have read on this says the same, namely that they don't come out without damage to the thread.

Bodger's solution, (You didn't hear it from me), drain the coolant out, let everything dry off, mix up some two part adhesive of the liquid metal type, JB weld or whatever and cover the core plug and surrounding metal, once you have cleaned it all up and given it a bit of a rough sanding to provide "grip"
https://www.google.com/search?q=why...ome..69i57.5709j0j15&sourceid=chrome&ie=UTF-8
Let it cure overnight. Then. refill and go. TBH, I prolly wouldn't even drain off the coolant, I might just jack up that side of the car. Many epoxy adhesives set under water anyway.
See https://www.google.com/search?q=epo...hUKEwjTi7KwpMbvAhX0nFwKHScWAuIQ4dUDCA0&uact=5

I have to say K seal is very good, we used it at work for years, and it kept many a leaking rad/engine going along nicely.
Use it on a friends vw whos rad sprang and a leak and they had zero money for a new one, rad was still dry when they scrapped the car 8 years later
Kept my leaky s2 rad going for a year or two, and that was in a proper sad state.

benh999 said:

Morning folks, my TD5 has sprung a coolant leak from the core plug on the head that sits semi obscured by the manifold.

Is there advice or guides for removing the manifold and changing/re-seating the plug?

many thanks

Ben

Click to expand...

If you decide to strip it get the engine up to normal operating temperature, it will give you a better chance of getting any partially seized fixings out.

Andy Warren said:

If you decide to strip it get the engine up to normal operating temperature, it will give you a better chance of getting any partially seized fixings out.

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Depressurise the cooling system though.

Andy Warren said:

If you decide to strip it get the engine up to normal operating temperature, it will give you a better chance of getting any partially seized fixings out.

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Isn't this going to be difficult with the exhaust manifold removed? I would agree with the principle though.

PopPops said:

Isn't this going to be difficult with the exhaust manifold removed? I would agree with the principle though.

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If it was me, I'd loosen off everything that isn't likely to be causing a problem, then warm it up, then take everything off.
maybe this is what he means.

Stanleysteamer said:

If it was me, I'd loosen off everything that isn't likely to be causing a problem, then warm it up, then take everything off.
maybe this is what he means.

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Spot on Stan, like you I crack undo what I can before I start, then warm the engine up to temp. & start stripping (not me but it has been known) the bits off I need to, adding extra heat/penertrating oil if necessary.

Does anyone know what thread size the plug actually is so I can have a new one ready to go?
Thanks.

benh999 said:

Stripping the threads worries me

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Quite rightly!
My advice is to cut the nuts off if you possibly can then take the manif off.
Get it skimmed then put it back on distrubing the studs as little as poss.
So many of us have had to take the manif off and then had a world of pain drilling out the broken off studs.
Me being one of these!

Just noticed how old this thread is!!!

benh999 said:

Morning folks, my TD5 has sprung a coolant leak from the core plug on the head that sits semi obscured by the manifold.

Is there advice or guides for removing the manifold and changing/re-seating the plug?

many thanks

Ben

Click to expand...

I managed to replace the core plug on my Defender Td5 by de-webbing the manifold (between cylinders 3&4) in place. See photos.