Re: [OMC-Boats] 1ST RUN CHECKLIST

Ethan's revisions are what makes this list and exchange of ideas well
worth reading.

And Ethan experiences much colder ambient air/water temps than I'm
willing to experience! (But we've experienced an extremely cold and
wet June). I am also pretty sure the chokes on these GM engines are
NOT really required at the temperatures most of us boat at, to insure
quick starting. As Ethan noted, overly rich idling can wash down
lubrication do more harm than good.

I ran the 307 Chevy (QuadraJet) with a missing bi-metal coil
(divorced) choke rod for several seasons and never experienced any
cold starting issues. I finally located a rod and now I don't see any
difference when inspecting the spark plugs, which is my primary way of
checking for evidence of richness at the high altitude I operate in.

If my boat gets used daily, weekly or even bi-weekly, it always starts
right off without any need to crank over the original mechanical fuel
pump. It has to sit about 2- 4 weeks before any prolonged (more than
30 - 45 total seconds) cranking is necessary. Maybe the fuel
evaporates, I dunno where it goes?

Ethan is absolutely correct you shouldn't spin a dry impeller. (And do
as he suggests, never! I usually only do it if the launch line is
really long and I want to have it immediately be ready to fire up when
I hit the ramp water line, but it's still NEVER a good idea).

I also usually shut off the motor when docked and waiting for my wife
to return from parking the trailer, but then its usually 70 to 90 F
(ambient). It's amazing how little (water) temperature increase
occurs when just idling or underway of say less than 1500 RPM's. (And
getting up to operating temps quickly is more efficient, no argument
there.) Now I'm interested in tracking an oil temp sensor just for
curiosity.

It also amazes me how little the engine manifold temps drop when
docked for a 90-minute lunch after running at operating temps (usually
skiing or tubing). I can get back in the boat and still have 125 F,
there's a lot of mass to retain those btu's I guess. My dog loves
sleeping up on top of the engine cover (when docked), especially when
it's cold and windy.

Lee Shuster
Utah

On Jun 15, 2009, at 6:53 PM, Ethan Brodsky wrote:

> On Mon, 15 Jun 2009, Lee Shuster wrote:
>> When I arrive at the lake, and I'm in the launch line here's my
>> procedure:
>> ...
>
> That does sound very thorough and effective at preventing problems
> (though
> I seriously question the wisdom of turning the drive over *at all*
> without
> having water going to the pump), but I've been using a much simpler
> procedure for ~5 years with pretty good success. I have the 155 hp
> V-6 and
> it has an internal automatic choke built into the carb (though I am
> pretty
> sure it isn't working, as the line is disconnected). Here is my
> procedure:
> - make sure drain plug is in
> - launch boat with outdrive partially raised, tie to pier
> - turn on blower for a minute or two
> - usually peek under the engine compartment lid for water or fuel
> - lower outdrive entirely
> - turn key to run, give (electric) fuel pump a few seconds to build
> up
> pressure (can tell because the sound changes)
> - pull throttle all the way back to idle, keep drive in neutral
> - set throttle a tiny bit off idle (maybe 1/2" or so)
> - crank until it fires, usually within 3-4 s
> - if it won't start, pump throttle once or twice while cranking
> (usually only necessary with air temperatures close to freezing)
> - if it starts and stalls immediately, give it a bit more throttle
> and
> try again
> - once it does start, let it high idle (~1000-1500 rpm) for 30 s
> to a minute while everyone gets on
> - pull fully back to idle (600-700 rpm)
> - push "reverse" button and back away from the pier
> - "taxi" out to "no wake" buoy 200 ft from shore at or just off
> idle -
> (2-3 minutes)
> - smoothly but quickly advance throttle to full, then pull back to
> ~3/4
> throttle a few seconds later, once the boat is on plane
>
> I know it's bad to heavily load a cold engine, but I'm not convinced
> that
> warming up at idle is much better. For a modern engine, the best
> thing you
> can do is to warm them up rapidly at moderate power - I'm guessing
> that's
> less true for these 40 year old designs, but for cold-starts at
> above-freezing temperatures, there should be little harm in immediate
> application of moderate power. Even with older engines, warmup at
> idle can
> actually be detrimental, as they tend to run very rich when cold,
> washing
> away the oil film on the cylinder walls. I doubt there's any harm for
> the lengths of time and above-freezing temperatures we're talking
> about
> here, but it's something to consider.
>
> Ethan
>
>
> --
> Ethan Brodsky
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Received on Monday, 15 June 2009