Inlet manifold

[mikemcd]

After idling and mixture issues with my 1979 2000 Berlina, I've had the carb (34DATR) completely refurbished. Some improvement but still an issue - identified as a leak around the manifold. New manifold gasket fitted (making me appreciate how crowded the engine bay is!) but problem persists. Running too lean - still a leakage. A close inspection of the manilfold shows no evidence of cracks etc. It appears therefore that the manifold is porous - confirmed by the fact that spraying brake cleaner/WD40 on the body (not the joints) of the manifold produces a temporary improvement.
I can't find any information on fixing a porous manifold -  very grateful for any ideas, or, more likely, where I can get a replacement manifold.
Many thanks Mike

[Nigel]

That's very interesting Mike, and a first for me.

Have you managed to isolate a spot or spots where the carb cleaner reacts?
Assuming you are spraying on top, or at least the visible areas, if an area is
identified, cleaning and roughing with sand paper may expose some visible faults.
My only thought would be to use 2 pack araldite or similar. But this would only work in
specific identified areas.

A replacement manifold is the better option. This should not be hard to find from one
of the readers on here. I can't think of a reason why the 1600 manifold would be different,
so that may widen your options. Try Mark at BetaBoyz as well.

Good luck, Nigel

[peteracs]

Hi Mike

I have some spare manifolds, a photo of yours with takeoffs for vacuum points would be useful to identify it.

Peter

[mikemcd]

Peter
Much appreciated.  Manifold is back on the car and it's too dark in the garage to get decent photos - will try tomorrow, rain permitting. Looking, and feeling, around I detect only one outlet for vacuum - this is right at the front, slightly off centre, of the manifold with a screw-in angled connector. That mirrors the picture in the series 2 parts book I have which gives two numbers for 1600/2000 manifolds - 82332210 or 82331097. Is there something I should particularly look for? I don't really want to take the manifold off again ( I needed help last time) until I'm pretty confident I've the right replacement, partly also because my garage entrance prohibits me getting the car in and out except under its own power.
If you have a potential replacement I'll be happy to pay up front and then see if it's correct, or whatever arrangement suits.
Many thanks again,
Mike

[peteracs]

Hi Mike

Let’s do it the other way round, sounds like a standard inlet manifold with that take off. I will take a photo of the one I think you need and you can compare to the best of your ability given the limited access.

Then can take it from there. Should get to dig one out tomorrow.

Peter

[peteracs]

Email sent with photos.

Peter

[mikemcd]

Many thanks again to Peter for looking out a manifold and sending some photos - much appreciated. Unfortunately this one wouldn't work as mine has a fitting on the front to which a retaining bracket for the alternator is bolted. This mirrors the arrangement shown in my Series 2 parts book, which gives the number for the 2000 engine as 82331097 -others may fit but it does need the alternator connection.
There are currently 2 manifolds on eBay but neither would work. I'll keep looking, but I thought it worth investigating whether some, perhaps temporary, solution would  work while I look - perhaps a coating of epoxy resin, as already suggested, or even high temperature engine paint (there are no obvious cracks or other damage to the manifold). I gather a porous manifold like this is pretty rare but I've found some discussion of the issue on other clubs sites. It seems more commonly to involve water leaking into engine - something that one of the propriety leak preparations should cure. One club site claims that Aston Martin used to routinely put 2 bottles into their car's cooling system when new. I now suspect my car may have had the water leak issue as about a year ago I started getting steam from the exhaust - cured instantly by a leak product. I wondered then if it was to do with the head gasket, but as it had a recent new gasket, perhaps it was the manifold starting to go.
Very grateful for any more thoughts.


Mike