Join Date: Jul 2007
Location: Truckee, CA
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Re: Tohatsu 4hp 4 Stroke won't run on integal tank
I have the 6HP version and have always used the integral tank. It looks like the external connection has a "t" connection, one side external, the other side coming from the "selector switch", or integral tank shut off valve. Mine has a very tight rubber cap over the external male fitting. Yours may be leaking air into the system? Or the selector valve may be bad?
You could connect a "Jumper" hose from the Integral tank outlet hose directly to the fuel pump as a test. If the external connection is leaking when running it may indicate a bad surface connection with both the hose and/or the rubber cap, allowing it to suck air? Let us know what you find. Just a thought, the selector valve should be in the "down" position for integral tank use.