View Full Version : Osco center riser??????

11-07-2012, 07:49 AM
anyone have a diagram of the water flow and different gasket sets for the osco

the reason I ask I am noticing some scorching of the paint in the area where the risers bolt to the manifolds

I have seen different gasket sets that either allow or deny water in the four outer water passages front back left and right that surround the exhaust chamber

the one gasket I saw looks to block the two side and back one holding more water in the manifold then letting it pass thru the front and run along the top of the riser

just wondering if this is normal( the scorching) ? or do i have a water flow issue?

11-07-2012, 09:53 PM
I think the earlier engines used the gaskets where water flowed through all four ports and the later engines used flow from two and the other two blocked off. I think partly due to raising engine temp. The dry joints now block them all. The water will back flow into all the ports I think what you are seeing is normal

11-08-2012, 08:59 AM