Replace MDKD

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MauleOne

Veteran Member
Joined
Jan 22, 2011
Messages
58
Our ONAN is getting old and is very under used. It is also heavy and noisy.

The weight is a big problem as the stern of our boat is low already.

It is rated at 8.5 KW which is way more than needed on our 38ft Bayliner.

I would like to replace it with something smaller but still diesel. Probably less that 5 KW.

What is available these days? I can't be the only one with this idea.

Thanks
 
Phasor makes a nice unit at a decent price. we also have an Onan MDKD. We are having some issues right now. Where are you located.
 
So far as I'm concerned the only generators worth buying these days are Northern Lights. They're not cheap but they're worth every penny in reliability and performance. I believe their smallest unit is 5kw but they might make something smaller. Northern Lights, Inc.
 
For the cost, reduction in weight and age of the boat its probable not worth it?

I plan on running our old gen until it dies as it not worth the time and money to replace as long as it runs/works. Heck, if the old gen can be rebuilt in place, that is what I would do first. When it come time to replace I will look for a good/rebuilt used gen set as is not worth buying a brand new one. :confused:



 
I plan on running our old gen until it dies as it not worth the time and money to replace as long as it runs/works.

That's our policy, too. Our boat came with an Onan Jurassic Edition MDJE 7.5kw generator and so far it continues to run as advertised. If or when it dies beyond a reasonable fix we'll replace it with a Northern Lights.

If we elect to proceed with our total overhaul of the boat the Onan will be replaced along with the engines. But other than that we'll run it until we can't anymore.

That's pretty much our philosophy with everything on our two boats--- we don't replace anything unless it fails beyond a value-added repair or it no longer does what we need it to do in terms of capability.
 
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I just put a new Nexgen 5.5 kw genset on our boat. I bought it because it was the lightest, most compact unit that I could find. It cost approx $7,500 new at the Seattle Boat show. Dry weight with sound shield is 270 lbs. It fit perfectly into the space we had in the engine room. It seems relatively quiet to me with the sound shield. The engine is a Kubota. My mechanic that installed it was impressed with how it was built, how simple it looks to maintain and the responsiveness of the support folks. I don't have enough experience yet to tell you about reliability.
Lyle
 
If you want to sell it my neighbor is looking for something about that size. Oh yea, if your close to Mississippi.
 
We have an MDKD 6.5kw on our 1981 IG,looks to be a replacement 1983 model(for an MDJE) and to have been rebuilt by the local Onan marine agent at some point for a PO. Recently we changed the fuel filter head which was bent causing massive leaks, and just bought a new fuel solenoid to fit,lately I`ve been closing the solenoid manually to start it,seems the internal switch for the "start" and "hold" devices is defective. But overall it is a good thing and I`m happy to maintain and keep it. Once started it quietly and reliably churns out amps. Keep it if you can. BruceK
 
We have an 8 kW Northern Lights and had a 4.5 kW Northern Lights on our last boat. Both generators have 3 cylinders. Some of the smaller gensets only have 1. NL's run at 1800 rpms vs most of the smaller gensets run at 2800 or 3600 rpms which does shorten their life and increases noise. Northern Lights probably has more generators out here than any other manufacturer so support and parts availability is great. Of people looking for assistance on their generators, while we're out cruising, I would say the majority of them are for the smaller generators.

That being said, if you are only going to use the generator on occasional weekends or on your annual cruise, I think some of the 2800 or 3600 rpm generators are fine. IMO though, they are not designed to run day in and day out, that is where the 1800 rpm generators shine such as the Northern Lights. When ours goes, well buy another Northern Lights.
 
We installed the 8 kw Northern Lights on our 4788.

It is very quiet.

As others have said, the Northern Lights units are what others compare to.
 
I would like to replace it with something smaller but still diesel. Probably less that 5 KW.

A Honda 2KW or 3Kw can be used aboard with an OB gas tank.

No noise , almost no maint , 1/3 or less the co$t of "marine".

And you can take it home to handle power outages as they become more common.

Here in CT a week seems the norm.

FF
 
The problem is it is gasoline powered with all the attendant possible "gotchas" as well as open exhauset. If could eliminate the hazards from those two factors than they are possible.

I used one plumbed to a 2 and 1/2 gal OB tank on my 29 foot Aquasport tournament master. Had it mounted up on the tower and had CO2 detectors as well. Never ran it at night while sleeping but it did good during the day. The Honda 2000 is a great machine. Mine is 9 years old and still cranks on about the 2nd pull.
 
Gen

Baypoint

I am located in Valdez, AK

I am in the process of doing some upgrades to my 3870 and sure would like to get some of the weight off the stern.

Every one says just to live with it.

I guess we will see.
 
Don't live with it ! The NextGen machine referred to above is an excellent machine & if you just wanted to swap out to a smaller genset, I'd go that way. But if you really want to get weight way down, go instead for a diesel DC genset...that's right, DC. It will direct 200A to your House bank and then you can make AC power from the house bank using an inverter(s). A DC genset is super light weight, inexpensive & efficient. Hopefully, the charge from your engine alternators is already externally regulated and directed to your House bank too, further reducing genset demand.
 
A DC genset is super light weight, inexpensive & efficient.

None I have seen are in a size worth installing (200A or better)..

To do this right a 300A 12V or better 24V alternator would be hooked to a Kubota or Yanmar . Speed would be controlled by the charge required and air cond ot heavy 120V loads would come from a 4000W or larger inverter.

This would be an "ultimate" silent living setup with AGM batts with their more rapid charge rate.

But not cheap to effect , unless it was a DIY for the genset and used inverter.

Last 4000W inverter 24V I saw was $2500 wholesale.

FF
 
Here is one source of DC gensets that would certainly be worth installing: 5.5-20kW DC ! Looked at the price of a brand new 9kVa+ genset supplied/installed lately?

Polar DC Marine
 
Ahhh yes the DC gen set.

Here ya go very affordable DIY set up. :whistling:

510d1054788725-weed-eater-engine-conversion-weedeater-genset.jpg
 
We met a full time cruiser this past winter that has the equivalent of the G12/280 by Ample Power. It has a large frame - 250 (?) amp alternator driven by a 3 cylinder Kubota diesel. Small size and simple. I believe this is what FF was referring to.

Genie Diesel Alternators
 
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i just repowered with a refurb NL 5KW (the NL 5kw was highly recommended to me by several independent parties)
cost was apprx $7K incl installation.

let me know if you are interested in a contact for the refurb seller (in Florida).
 
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