Sort of depends on the overall condition. If the manifold is generally
in poor shape and there is the possibility that water may also be
leaking into the exhaust area you could have big problems. Water
leaking back into the exhaust and possibly into the cylinder can cause
major motor damage.

If you are certain it is only leaking outside you can try epoxy to see
if you can seal it. Most people find epoxy works for a while and then
fails due to expansion/contraction. But some of them are ok with
applying new epoxy once in a while :-)

Replacing the manifold is not really a very hard job. It is heavy.
Soak it down by occasionally applying wd40 or penetrating oil of your
preference for a while before attempting to take it apart. The worst
case scenario while removing is breaking off bolts in the engine block.

Steve wrote:
Would be very grateful for insight/experience with the following --
Found about a 2" crack in port-side exhaust manifold on '84 Wellcraft
(200 elite 260HP merc Runs horizontal, center, sort of low. Little bit
of rust, water seepage. Evidently been there awhile...

Few questions from stupid ?? dept.:

-- Worst case scenario?? How urgent is need to fix?
-- How big of a repair job is it? Time/effort/cost... (Other stuff
that'll need fixed due to this)
-- Any recommendations on DIY vs shop


THANKS in advance

STB