RP Top Water Outlet Manifold.

[Smiley]

Hi Folks, Thought I would attend to a leaking Top Water Outlet Manifold today.  I managed to get the nut off the top with not too much effort.
Having removed the top hose, I then hit a further problem.  I find that the neck of the Outlet Manifold is badly corroded and is in a very delicate state.
The Manifold does not want to release itself from the stud.  I have given it a splash of WD40 but as yet it doesn't want to release.  
I managed to get around the Gasket with a stanley knife thinking that may be holding it but no joy there.  
I have thought about carefully drilling the Manifold down the side and then splitting it to release it from the stud.
Does anyone out there have any further suggestions on how to release it from the stud. ? 

[Rogerchummy]

I would have thought that some gently twisting of the manifold backwards and forwards should release the "weld" that the corrosion between the stud and the manifold has created. Worth a try before the drastic action you are contemplating. Bear in mind that if all else fails and the manifold cracks, they are readily available quite cheaply from David Cochrane at A7 Spares (david@a7c.co.uk)

[Chris KC]

I take it we are talking about a low compression head (single bolt fixing)?

The thing to be careful of is stripping out or breaking the iron 'strap' in the head casting which the stud is threaded into.

As for the ally manifold, I'd point a blowtorch at it for a minute or so. They are readily replaceable if it goes bad.

[Smiley]

Thanks rogerchummy, I did try that but the Manifold started to break up.

[Smiley]

Thanks Chris KC. yes it is a low compression single bolt.  1932 RP.
Cheers.

[Reckless Rat]

WD40 isn't a release agent, it's a water dispersant (from whence comes the WD). Try PlusGas or similar and the warm spanner.

[AustinWood]

It's very likely that the stud in the cylinder head is corroded and weak.
From your description it seems a new new water outlet will be needed so perhaps just cut the aluminium outlet down beside the stud. A couple of cuts should release it. The stud and head can then be inspected.
The whole of this area can be fragile.

[squeak]

What do the forumists think of replacing the manifold with one of brass or bronze? Is this likely to reduce corrosion?  Is it likely to stick on more fiercely when time comes to remove?
The aluminium looks to behave as a sacrificial anode, so is reduced corrosion at this location likely to promote it at another?

[Colin Reed]

HI Squeak,
A Magnesium Engine pencil type Anode is one way to help, fitting just requires a 1/4 or 3/8 brass Plug with the magnesium rod screwed in fitted in the Head and one in the Block, any marine outlet will stock them

Colin
NZ

[squeak]

Good idea Colin, do you use them and exactly what location if so? Is there likely to be any effect on the radiator solder?
regards  Russell