Expansion of Disimular Metals
The difference in expansion/contraction between aluminum and steel is a 17/1 ratio. In the cold a exact piece of aluminum will shink .017" to steel's .001".
That said, the bolt an the aluminum housing are very different in shape and mass, but, the aluminum is higly likely to shrink a greater amount.
More than likely you have a gasket/seal issue between the waterpump housing and the engine. Try loosening and retorqing the bolt, do not just try to tighten or check the torque on a bolt that has set for a long time, it is inaccurate at the torque levels involved. Worst case, and I do mean worst case, is R&R of the waterpump, which on most Shadows can not be done with the engine bolted down.
The difference in expansion/contraction between aluminum and steel is a 17/1 ratio. In the cold a exact piece of aluminum will shink .017" to steel's .001".
That said, the bolt an the aluminum housing are very different in shape and mass, but, the aluminum is higly likely to shrink a greater amount.
More than likely you have a gasket/seal issue between the waterpump housing and the engine. Try loosening and retorqing the bolt, do not just try to tighten or check the torque on a bolt that has set for a long time, it is inaccurate at the torque levels involved. Worst case, and I do mean worst case, is R&R of the waterpump, which on most Shadows can not be done with the engine bolted down.