Check this site:
I have used these for emergency starters on some of the racing
sailboats I use to crew on in a different lifetime. Would keep one
oiled and bagged in case the starter went on the charging motor.
--- In AtkinBoats@yahoogroups.com
, Rob Rohde-Szudy
> Hey Curtis,
> Glad to hear you're getting ready to weld! (Remember to run your
practice beads on scrap!)
> You're not likely to see a pull-start diesel over 5 hp. It's WAY
more compression to pull against than a gas engine. You need a
starter. The old Caterpillar diesels way back in the day had a
gas "pony engine" that you'd hand start. It shared coolant with the
big diesel, so it would warm the block. Then you'd ease in a clutch
to turn the diesel over until it fired on its own. Sounds like a pain
in the butt.
> You must plan to moor RM in salt water. I guess I can't offer much
wisdom on electrolysis, since I live 1200 mile from the nearest
saltwater. And since you can go so many more places with a trailer, I
don't give mooring much thought. Though that is something to think
about, since saltwater is corrosive and trailers are handy. I also
expect the resale value would be better with a trailer, since it
would make it more available to the great many of us living on
shallow water in the interior. Something to consider.
> In any case, you are going to be thinking more about "how much"
electric than "if" you'll have it. You need nav lights and kerosene
is both too dim and illegal for powerboats (I seem to remember).
These can have a self-contained ground to the battery, e.g. no
electricity to the boat. Of course the same is true for the starter
adn ignition system. On the other hand, by APPLYING a small current
to the hull you can PREVENT corrosion. Look up electrolytic rust
prevention. It's like backwards electroplating in slow motion, sort
of. They use this on steel bridge pilings. And of course there are
sacrificial zinc anodes.
> I guess what I'm getting at is that is saltwater you're going to
have to learn enough electrochemistry to control corrosion ANYWAY. I
suspect that if you're learning that much, it wouldn't be a big deal
to have a gas engine or electic starter. Having an air starter is
nice because the salt air won't ruin the starter, but I don't think
it will make much difference to the hull. Same deal with the
distributor of a gas engine.
> Caveat emptor, though. I live a long way from the briny blue.
> Careful of that outboard idea, though. I think it would actually be
mechanically easier to do the inboard Robb White transmission.
Really! It's not as simply as bolting up the outboard's cavitation
plate to the tunnel. You need the water pump submerged, but there's
no water in the tunnel unless the prop is turning. You'd have to
leave the motor in gear and you'd still have dry start-ups, which
ruin the impeller pretty fast. So you'd really want the pump on an
intermediate shaft - a belt from the powerhead to the intermediate
shaft and another belt to the lower unit. You'd also need a cover
plate with shaft seals on the lower unit or it might leak air into
the tunnel. They're not all that airtight. So you'd have to mess with
the same bearings in either installation.
> Unless you can get a good outboard DIRT cheap, I would look for a
cheap gas or diesel industrial engine and get some Type B belts and
sheaves. The shaft is easy enough to ship to someone for machining.
Or maybe you can find a sailboat shaft and log assembly from someone
whose engine died and they switched to an outboard. Happens all the
time. Cutting a shaft to length and mounting a sheave is easy. A
pivoting motor mount isn't too tough either. You could skip the
reverse gear until later to simplify matters. Just leave some space
to install it.
They work very well.
> So I think that if you're planning to install the power yourself,
Robb's setup might well be the easiest for the amateur mechanic.
There is a LOT less messing with close tolerances. Belts are great
that way!! If you're worried about the cost of a diesel and
transmission, just think what it would cost if you can't get it
aligned right and have to take it to a marine mechanic after you've
been messing with it. Or worse, you don't notice it's misaligned and
ruin something! Like I said, this is where belts are great - lots of
wiggle room for us amateurs to say "close enough". Under 25 hp or so
the tensions on a V-belt are under 400 lbs. A lever with a big spring
is enough to give this to us.
> I'd change one thing, though. You will likely want to use a longer
shaft than Robb and mount the engine backwards. Then you can use RH
props and save money there, and Atkin's splayed shaft will work as
intended. Of course it will work with the reverse splay Robb used,
but LH props are harder to find.
> Sorry if I seem like a cheerleader for Robb's transmission. It just
seems both cheaper and easier for someone doing his own installation.
If I were you I'd find a good deal on a Kawasaki (or similar) gas
engine and put it in with belts. You can always upgrade to diesel
when you repower, or sell this one when you build your bigger (and
> Hey, where are you located? We have TONS of machinists here in WI.
I have one in the family too. Why don't you email me privately and
I'll see if I can hook you up with a better price (and a less blank
stare) than you're getting out there.
> Do you Yahoo!?
> Everyone is raving about the all-new Yahoo! Mail Beta.
> [Non-text portions of this message have been removed]