> Today I noticed that the end corner of my manifold gasket is torn and
> cocked a bit out of line. This is at the very end over an exhaust port. I
> fired the engine up and sure enough, I could feel hot exhaust gas
> pulsing out from the gap. This explains the exhaust smell I've always
> had in the cockpit. Now I'm a rank novice when it comes to auto
> mechanics, so let me know if my reasoning is faulty.
>
> Assumption one:
> The leak hasn't hurt anything, some of the exhaust has just come out of
> the engine compartment instead of the exhaust pipe. (The engine does run
> well.)
Short term damage is nil. Eventually the gasket will blow out, exhaust will
get loud and manifold will start to erode, and then you will have problems.
Remember exhaust fumes are not good for the lungs.
> Assumption two:
> The gasket was probably torn by the DPO during an engine rebuild because
> there really isn't enough pressure in the exhaust manifold to blow the
> gasket out like that. (Exhaust manifolds don't get plugged up, do they?)
No!
> Now is it essential that I replace the gasket, or could I fill the gap
> with some gasket-in-a-tube stuff without removing the manifolds? If the
> gasket-in-a-tube
> stuff will work, what brand should I try? Is it a difficult job to
> replace the gasket? If I replace the gasket, is there a torque spec on
> the manifold clamp nut? (You can tell I've never torn an engine down.)
Don't mess with any goop-in-a-tube. Replace the gasket. It is no big job.
Here is how it goes:
1. Remove three exh. flange nuts from bottom of exh. manifold, and drop
front pipe.
(note) Front pipe must be dropped because the long studs from the head will
not permit the manifolds to be removed if the front pipe is still connected.
2. Disconnect all carb linkage and fuel line, pump to carb.
3. Remove four manifold dog nuts and dogs.
4. Remove intake manifold and carb assembly.
5. Remove exhaust manifold.
6. Clean all flange surfaces.
7. Replace exhaust manifold and flange gaskets.
8. Reassemble in reverse order.
No there is no torque rating for manifold nuts. I would suggest 15 ft/lb.
Press on regardless,
Blair Engle
The Classic MG Shop
______________________________________________________________
Blair Engle engle@phy.fsu.edu
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