Engine Size?

[SV_Galateia]

My wife and I are desiring to do some east coast cruising but my wife would also like to do the loop via sailboat.

We are looking at a 35 ft boat displacing 15000 lbs powered by a Yanmar 3gm30f with a 3 blade prop.

The 3gm30f is listed as 24 hp at about 3400 rpm and 27 hp at 3600 rpm limited to 1 hr.

For a sailboat, I feel the 3gm30f would be fine in almost any situation (it is primarily a sailboat) but my concern would be on the river portion of the loop (the mast will be down). I think there is a section where you have to go up river against a pretty strong current and have concerns if the 3gm30f has enough hp to get through that section.

Would like to hear others opinions.

Thanks

[rslifkin]

It should be fine for the loop. You won't be fighting sea state, just current on the rivers. So if it engine can push the boat to hull speed in calm water, more power won't help. Fortunately most of the running on the river sections is with the current rather than against it.

[gonesail]

up current will be much slower and more challenging. if you don't mind 4 knots then you will be fine. if you do the intracoastal you will also be faced with strong and adverse tidal currents. seems like your boat may be a bit underpowered but the 3GM is reliable and easy to maintain and work on.

[donradcliffe]

Its a bit underpowered, but as long as you do the loop counterclockwise you should be fine. The biggest head current I experienced was 2.5 knots on the short section of the Ohio from the Mississippi to the Kentucky.

[valhalla360]

We did the loop in a 34ft sail catamaran with a 25hp outboard. While a monohull, your power needs won't be substantially different.

When doing the loop, you purposely go counter-clockwise due to the river systems.

Starting at Chicago:
- Illinois River: You are going with the current (though it's typically not much). It varies a lot depending on where you are in relation to the dams.
- Mississippi River: This is where there is typically substantial current. 2-3kt current is common. Our 2nd time the river was borderline flood (we had to wait for the river to ease up before the lock at St. Louis would let us thru). At about 4kts STW, we were making 10-12kts SOG at times. We docked at Hoppies (just south of St. Louis) at full throttle to counter the current.
- Ohio River: Typically 1-2kts against you, so if your cruise STW is 6kts, you are still making 4-5kts SOG.
- Tennessee River: Again, it's against you but with regularly spaced dams, it varies from no current upstream of a dam to 1-2kts on the downstream side of dams.
- Tom Biggby: Current is again at your back, with similar pattern to the Illinois/Tennessee, your relation to the dams will have a big effect.
- On the ICW, you may have tidal currents but you can time them in your favor. Around Georgia is the only place where it really has a big impact.
- Hudson River: Currents aren't really bad and they are tidal until you get up around Albany.
- Nothing significant on the Erie Canal.
- We didn't take the Trent-Severn route but I've never heard of any issues with currents.
- If you go the Detroit Route, you can avoid most current upbound by hugging the shore. On the St. Clair River there is about a 1-2 mile stretch under the Blue Water Bridge where you likely will have to run at full throttle. When we did that stretch, we were making less than 2kt SOG at full throttle.

Obviously, flood conditions can have a big impact on currents but many folks do it with similar cruising speeds. Make sure the engine is in good running condition and you have sufficient fuel range and it should be fine.

[Adelie]

Engine is more than big enough to hit hull speed. In protected waters with little sea state lots more power will only get you 0.2-0.4kt improvement. The river sections where you are going up current are protected so little or no sea state.
The current motor should be just fine for all the river portions except at flood stage then you might want a longer boat and a bigger motor. Without the longer boat bigger motor is not going to significantly improve the situation. If a river is running very high or at flood stage you probably want to wait for several weeks for it to subside.

[Sailer_Med]

I run a Volvo D1-30 saildrive on a 7700kg 11m modern design (2006) SV. I find that in the calm I can see about 7.5 knots @ WOT. If you need more...gonna need a bigger boat.

[SV_Galateia]

I really appreciate all of the responses. I do understand clockwise vs counter clockwise for this trip with counter clockwise being the prescribed direction. As stated, my biggest concern was the Ohio/Tennessee sections going upstream.

I have to admit, I did not give much thought to the tidal currents of the ICW. I do feel these will be more manageable as they do come and go with the tides and therefore can be planned for where as the river currents are pretty much constant.

I watched a YouTube channel where they went through the loop on a Tartan 37. The upstream section seemed....VERY INTERESTING....for them to get through, but they made it with no problem. The boat got pushed around alot by the strong currents. If your motor was to fail here things could go down hill very fast.

[rslifkin]

Originally Posted by SV_Galateia

I really appreciate all of the responses. I do understand clockwise vs counter clockwise for this trip with counter clockwise being the prescribed direction. As stated, my biggest concern was the Ohio/Tennessee sections going upstream.

I have to admit, I did not give much thought to the tidal currents of the ICW. I do feel these will be more manageable as they do come and go with the tides and therefore can be planned for where as the river currents are pretty much constant.

I watched a YouTube channel where they went through the loop on a Tartan 37. The upstream section seemed....VERY INTERESTING....for them to get through, but they made it with no problem. The boat got pushed around alot by the strong currents. If your motor was to fail here things could go down hill very fast.

That last bit is when having a good anchor ready to deploy is important. If the engine hiccups, get the anchor down first and then try to sort it out.