Second generator

[whoover]

This is kind of a generator question. I'm still searching the for the next boat and watching the market cool off. One boat has had its second generator removed during a refit. My question is are two gensets required on a 60'ish boat? I don't intend to being at anchor for long extended times and am not interested in extra battery banks and inverters. I'm sure that a smaller nighttime generator could be installed for evening loads easily if the original switching is still in place. Has anyone removed a second generator and wished they hadn't or were just as happy.

Thanks
Walt Hoover

 

[madhatter1]

Adding a second generator to our 46 convertible. Just picked it up yesterday. Any boat that is closed up and not ventible like a sailboat, LRC, or trawler is an instant hot box with no power. IMO you need at least a smaller backup to keep the juice on and run an AC or 2.

 

[Pascal]

It all depends on how you use the boat. If indeed you re not going to spend a lot of time on the hook especially away from where you can get parts, or a marina slip, then you probably don’t need a second gen.

I have a single gen on my 53 and that’s fine as we only use the boat locally in sofl.

On the other end, for extended cruising in the Bahamas, it is really nice to have a back up. In the last 15+ years spending a lot of time in Bahamas as a captain, every boat I ve run had two identical generators on which we ve put close to 20k hours. In that time, we ve never had a complete gen failure but there were a few times where I had one gen down for a day or two while making a repair. Glad we had a back up although again stateside we could have just gone to a marina for a night.

 

[JD5652]

My thoughts exactly here.

I just replaced one of my 20 kW gens during my major refit in 2021. Went with a Northern Lights which is same as my other older gen.

It all depends on how you use the boat. If indeed you re not going to spend a lot of time on the hook especially away from where you can get parts, or a marina slip, then you probably don’t need a second gen.

I have a single gen on my 53 and that’s fine as we only use the boat locally in sofl.

On the other end, for extended cruising in the Bahamas, it is really nice to have a back up. In the last 15+ years spending a lot of time in Bahamas as a captain, every boat I ve run had two identical generators on which we ve put close to 20k hours. In that time, we ve never had a complete gen failure but there were a few times where I had one gen down for a day or two while making a repair. Glad we had a back up although again stateside we could have just gone to a marina for a night.

 

[firbanks]

Second generator saved at least 1 long weekend on the hook - we were loaded with guests and genset had an issue an hour after departure. Also saved me from doing an impeller repair in 85 degree outside weather. Having two is great but putting a second one back in is a harder choice. I might be replacing one of them soon as my twin 1988 onans have some very hard to find parts.

 

[Captain Ralph]

On our 58, we run 30 & 9kw gen-sets and we have an inverter.
All three have important roles onboard during short hops, weekend or long trips.

 

[madhatter1]

Here’s a good example of why it’s a good idea to have one. Decided to exercise mine since we have a 4 hour trip one legged limping to the yard next week. Want it to work so my sons have power for the trip over. Other than the secondary filter issue I had in august it has been working perfectly. But not today. New issue where it’s tripping the engine fault. Has oil, belt spinning. Have to wait for it to cool down to check coolant level. Had I been heading out on a real trip it would have been a bummer.

 

[Captain Ralph]

Here’s a good example of why it’s a good idea to have one. Decided to exercise mine since we have a 4 hour trip one legged limping to the yard next week. Want it to work so my sons have power for the trip over. Other than the secondary filter issue I had in august it has been working perfectly. But not today. New issue where it’s tripping the engine fault. Has oil, belt spinning. Have to wait for it to cool down to check coolant level. Had I been heading out on a real trip it would have been a bummer.

I hope all is an easy fix. Bummer when good plan fall astray.
Please keep us up on your discoveries.

 

[madhatter1]

It's either coolant level or a faulty sensor. Plenty of raw water flow with a brand new HX. Have a few days to fix before we move the boat. Point is if you have the ability to have a 2nd gen it makes life easier. But only if it fits your requirements. SF/Convertible? An option of course. Big ole boat IMO a must have. No power and all the fun is done.

And not a bummer. Just boat life. Everything on your boat is broken, you just don't know it yet!

 

[racclarkson@gmail.com]

I found this thread interesting because of my personal experiences. Aslan has one NL 20KW unit. The back-up OEM 20KW was removed in '04 and not replaced. The plumbing, wiring and switching were all properly terminated and left in-place.

My NL did fail 3 years ago. Diagnosis was the generator end got wet likely from a leaking water hose. The prior owner was not much interested in anything past oil changes and turning the ignition key. I had NL rebuild the generator end and reinstalled with factory warranty ($6,500 plus in/out). The motor is perfect with a youngish 1,500 hours. With a 70A main breaker, never found enough load to trip it.

So, no fun w/o AC power. But, I do have full electronics (radar, autopilot, MFD's, depth, throttles/sync.; VHF, etc.) capabilities because I installed a 12V 150A alternator on my port motor. I heavy cabled this directly to the flybridge battery switch and breaker for the two paralleled electronics batteries. So, getting home isn't a problem. It takes no time at all with a full load to drain those batteries without a functioning charger. Added benefit is I can save generator hours on moderate days and maintain full navigational capabilities. I almost prefer to run generator off if I can't give it at least a moderate load. BTW because of its location, an impeller change is embarrassingly quick and easy.

The same time as the rebuild, I did find a nice 8KW NL rebuild (w/sound shield) and located a decent place for it in the ER. But as you might recall Aslan is for sale, and my interests lie elsewhere. Other than the one incident, I find NL's to be bulletproof.

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Anyway, those are my thoughts. Good luck and Happy New Year!

 

[Pascal]

Here’s a good example of why it’s a good idea to have one. Decided to exercise mine since we have a 4 hour trip one legged limping to the yard next week. Want it to work so my sons have power for the trip over. Other than the secondary filter issue I had in august it has been working perfectly. But not today. New issue where it’s tripping the engine fault. Has oil, belt spinning. Have to wait for it to cool down to check coolant level. Had I been heading out on a real trip it would have been a bummer.

Any steam out the exhaust? Louder exhaust? Check the coolant temp with an IR gun. Likely to be the overheat sensor which you can temporarily bypass as a test if the coolant temp is ok.

I always carry a full set of spare sensors

 

[Freestyle]

Original post wonders if a second gen is necessary on an over 60 foot boat.

Without a backup gen or inverter, I had my main gen die in Bimini while running running a 10 day spring break trip. We completed the cruise living on the Hatteras DC system while underway and staying in marinas rather than anchoring. It didn't kill the trip but as Dad/Owner/Captain I would have liked to have had a second gen or inverter to show these gusts a better time for a once in a lifetime experience for some.

My toilets and freshwater run on AC so that was the main downfall (I have the Dc substitutes in place but it takes too much work to convert mid trip). We didn't need AC in spring.

I have since added two 3kw inverters to power all house loads other than AC for about 12 hours at a time. I travel with a fuel pump, water pump, belts and other generator repair parts. Even I can get it running in twelve hours if I have parts. Parts are cheaper and take less space and maintenance than a separate unit. It's easier to keep one running than two. Marina dockage is also a marginal cost solution to generator problems.

My advice to a purchaser is that (i) two well maintained generators is better than one; (ii) one well maintained generator combined with an inverter system is second best; but (iii) you can have a lot of fun with a 60 footer and one generator anywhere within a half day cruise of a marina since you will have some cash for that when the time arrives. Figure out how you cruise and add the backup power that makes you worry the least and party the most.

Bruce

Freestyle
1986 62 CPMY (54My with ext)
Tampa

 

[whoover]

Thanks for the comments. It does make me laugh at how a thread can get side tracked but that what make the site so helpful. Installation of a second generator even if it's smaller looks like the way forward. I haven't laid eyes on this boat yet but the single generator will have to be taken into consideration.

Thanks
Walt Hoover

 

[dottieshusband]

I added a 2nd generator to my 63MY a few years ago. The boat already had a thru hull and strainer for a second generator. I got a Kohler 16ekozd, with a Decision Maker 3500 controller, with load sharing capability. My plan was to add 2 new generators, the 16kw, and an 11kw to replace the original 20kw Onan MDL4. Nothing wrong with the Onan, except age. With the load share capability, if either generator was overloaded, the 2nd generator would automatically start to accept the shed load... Great plan I thought.... to make a long story short, the Kohler proved to be so unreliable, without the Onan, I would have had a boat full of uncomfortable people many times... Eventually, after 4 service visits and many replaced relays... the Kohler is now reliable, and I have spare relays onboard.... but the bottom line, if you entertain a lot, having a 2nd full load generator is a very desirable feature.

 

[luckydave215]

I have twin 20kw gens.
As we sometimes travel hundreds of miles offshore I wouldn't go without the redundancy. Every eight hours the sleeping gen gets checked "under the hood" and fired. It is then bussed into load, and the previous working gen shut down.
Rinse and repeat.