Question on Starting, and some observations

[james]

Hello – We took our boat to the fuel dock today, and had an interesting experience during start up.  The boat had not been run in about a month.  The Port engine had to spin for about 15 seconds before it would fire.  That is a first for this boat.  Starboard fired right up.  Engines are 6cta 400 hp with nippon denso pumps.  The only thing different is that I had been using the lift pump priming handle on Port just to get a feel for it incase I ever have to prime and engine.  Any relationship?

 

Also, wanted people to know, that by following Tony’s guidance gets Intercoolers cleaned, installing some new turbo’s and taking some prop out.  The boat was able to get on a plane very heavy and with a dirty bottom.  It did this with out smoke at all.  Being an analog boat, my primary indicator is boost (Tach’s bounce around a bit).  I ran with the engines at around 2150 rpm and 20 psi of boost, was getting 19.7 knots.  That seems like a pretty good sweet spot, not asking too much of the engines.  Any thoughts about that as good cruising speed (I don’t have fuel flow meters so can’t get a good sense of where on the demand curve I am.

Topic

[Rob Schepis]

Dip tubes

If the return line has a dip tube then it remains submerged in the fuel tank.  If the return line is submerged air cannot enter the system via a fuel drain back due to a weep in a check valve in the fuel system.

[james]

Thanks for the reply!  My tanks were at about 1/4 fuel load.  I did bang on them down in the engine room and the echo’s indicated that they gauges were pretty accurate.  I don’t know what dip tubes on return lines are, so can’t really comment on that.  If you can tell me what they are, I can check.

[Rob Schepis]

Loss of Prime

Were you unusually low on fuel?  Do you know if your tanks have dip-tubes on your return lines?

[Author]

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