what size twins for a skagit?

[DMCI]

Western Gear in Seattle custom built the gearboxes. It took several versions to get them right. I believe they also made the quill shafts for the blowers.

I called on both those shops and The Gear Works (Ing Ramberg) was the only one that had a MAAG gear grinder outside of Boeing which was much smaller. (Not shouting, the Swiss always capitalize company names.) These were capable of grinding AGMA class 15 (spacing) helical hardened and ground gears. A bold step by Ing that put his company (not located in Philly) on the map!

[Stan D]

Twins on the low end of the power spectrum

Probably the fastest barge on Beaver Lake.

[DMCI]

Engineering estimate (wild stab) regarding twins.

I can report from recent experience that my 18 Skagit runabout performed beautifully with a single 90 Mercury outboard. In the Stern I have in addition to two batteries, a 19 gallon fuel tank. Total weight in the boat included all safety equipment and two fat guys.

Extrapolating from that, Chuck's boat, a 20 foot Skagit Express has all a power it needs with a single 115. Now the 20 express has quite a bit more weight than my 18 and therefore needs a little more power. Therefore I would suggest that twin 60s, if you must have twins. That accounts for loss of about 20% because of the twin propellers. I have always used that factor and it seems to work out pretty closely, especially for I/O's.

Twins have a huge advantage if you are running alone and losing engine. (See note below Re: kicker) Because engines are propped for twin application you will find that with a single engine only operation, you are limited pretty much to hull speed.

The blue boat will have a single 60. The 90 Merc and the 60 are similar in that 60 has two cylinders and the 90 has three cylinders. The 90 is about hundred and 50 pounds or so heavier than the 60. Twin 60s will therefore weigh more than a single 115.

In summary, the single 115 is about optimal in my opinion. Reliability, if that is of concern could be provided by the addition of a 10 to 20 hp kicker.

[DMCI]

Tim -

Keeping three 1957 Johnson 35's running (more or less in sync) confirms that you love a good...uh...challenge.

- Marty

However, there was a time when keeping at least two In Sync was not that big a deal. Witnesseth the following picture:

[Lootas1]

Okay, Dave. I don't think that picture proves the two motors are in sync. I put my magnifer (old people) on the pic and I see the boat is tied to the dock! Point 2. I don't believe a chick like that could handle that much boat. :NoWay1:

[DMCI]

That actually pretty good eyesight. I wasn't even sure from the picture that the woman had twins. Her kids must be in the forecastle of the boat.

If they did let her take it out it wouldn't go very far because the rope was tied to the bow to keep her from floating away.

The motors do appear to be about 1956 or so Johnson 35 hp outboards. Perhaps electric start and not counterrotating. But that's only conjecture on my part.