Removed mercruiser manifolds and installing a used set of Imco Powerflos. The mercruiser had hoses in the risers,the Imcos do not. Cap the holes on the gooseneck assembly or have 2 bungs welded into risers? Appreciate any advice. Thanks Gus

Pretty sure the power flows have bungs in the lower front of the manifolds and the water passages into the risers are internal from what I can remember from some I had awhile back. Just be sure you use new gasgets from Imco, their a light green color, just go on their site.

Two ways of plumbing it, if you have a four port thermostat housing you either have to change it to a two port housing
http://www.iboats.com/Thermostat-Hou...view_id.222066

or you need to run the two into a y connector..heres a diagram and eddiemarine.com sells them,the y is on the port side of the diagram.

http://eddiemarine.com/techsupport/a..._plumbing1.pdf

If your risers do not have bunges to tap in the hoses, then use one of mrfixall's options. The only problem I see is that the holes in the imco's between the risers and manifolds are not that large. I would install a water pressure guage to make sure you are having any high water pressure issues.

Thanks to all. That should get me on the water soon. 70 yesterday and 35 and snow today. Hurry up baoting season! Global Warming!!! Gus