Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Tightening Manifold Nuts on M3W

I have tried to tighten the manifold nuts on a number of occasions on my M3W (currently in over winter storage in the south of France) and using various sockets and ring spanners, succeeded to the limited extent of the tooling I have at my French house. I was going to buy a curved shank, thin ring, manifold nut spanner to take out to France with me at the beginning of June. Can someone please remind me of the size of the exhaust manifold retaining nuts on the S&S engine. Mine is 2012 vintage. I seem to remember that they are AF not Metric, which given the US origins of the engine is no surprise. If anyone can suggest a better tool, I would be happy to buy that. My M3W parts book lists the exhaust studs as 5/16" UNF x 1.7", but does not list the size of the nuts. 5/16" thread would normally suggest a 1/2" AF nut but I have a slight feeling that the nuts may have been 9/16", which common for a 5/16" thread, if softer non-corroding material exhaust manifold nuts are used (monel metal or brass), with thicker walls.

Wilson