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Question on Vacuum Hose Routing

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Right now the engine in my mud boat (83 EA-81) is running extremely rich and fouls plugs in matter of minutes following a carb and intake manifold swap from a Carter/Weber 1bbl to a Hitachi 2bbl. The intake I now have installed is set up a little different as compared to the one I removed.


Not knowing a thing about how to properly run the new vacuum hoses, I took a wild guess. Speaking over the phone with a mechanic last night, he gives me the impression that I have the hoses installed incorrectly and that this is probably causing my present problem.


The engine has no emmissions stuff on it at all. The EGR is removed and the intake EGR ports are covered with a piece of 1/4" aluminum plate. There is no PCV valve either.


This mechanic tells me that the simplest way to route the vacuum hoses is to plug everything on the intake manifold, and run a single vacuum hose from the carburetor to the disty advance unit. Right now he feels that by having the intake vacuum tied in to this hose that the intake is sucking fuel from the carb directly to the intake through the hose (yes, there is a hose connecting the intake and carb)????


Before I run outside and try this simple setup and spend another 2 hours toting the boat to and from the launch to run it, does anyone else have an idea on the simplest way to hook up my vacuum lines?

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yeah, don't




hook up dipstick side valve cover fresh air intake to filtered air port in air box


hook up oil fill tube side vavle cover crankcase air to pcv valve


plug all vacunm ports EXCEPT for the choke / secondary and distributor advance, connect those to intake manifold


make sure base timing is at 8* with advance line removed and plugged, and engine at 800 rpm

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