Active Active   Unanswered Unanswered

Onan Generator

Keeping your powerboat under power is a lot easier with good advice. Post your power systems questions here.

Moderators: Don Ayers, Al Benton, Don Vogt

User avatar
Corsair
Posts: 37
Joined: Thu Nov 12, 2015 11:18 am
Contact:

Onan Generator

Post by Corsair » Sun Nov 29, 2015 9:30 pm

I recently purchased a 1962 45' Constellation that has just 1650 hrs on the original engine. I doubt that the generator has even 1/4 to 1/2 of the hours on it as are on the 431 engines. It is a fresh water boat located in St. Paul.

The Generator is an Onan 10.0 MJC–3GR/22685. Serial No.: 0370169644 with a 220/110V Capacity of 10KW. It has a Closed Cooling System with Raw Water Heat Exchanger. Many of the original documents and manuals came with the boat except information on the generator. I spent some time with a great counter guy at NAPA and was able to identify much of the engine tune up parts. What I cannot find information on is the sea water pump. I would like to have information and supplies on hand to service the generator including impellers.

Is there a source for an operating and a parts manual for this equipment? also what is the correct impeller? I'm not sure why such a large generator was ordered with this boat. It has A/C, one electric heater, an apartment size refrigerator (aftermarket) and a two burner electric cook top. Any opinions on that?
Thanks for your input

joanroy
Posts: 686
Joined: Sun Jan 29, 2012 1:46 pm
Contact:

Re: Onan Generator

Post by joanroy » Mon Nov 30, 2015 9:18 pm

If you Google Onan generator you'll find dealers who can advise. Good possibility the generator wasn't original equipment and was installed later. My 1948 cruiser has a Kohler generator installed in the early 1990s. When I got my boat 8 year ago, I spent a lot of time and money getting it working. I've used it a couple of times since. I have shore power at my slip so I don't need it. I guess if your on a mooring or anchorage a generator could come in handy. I'm thinking about pulling mine out so I don't have to service, maintain, and winterized it every year.

User avatar
Corsair
Posts: 37
Joined: Thu Nov 12, 2015 11:18 am
Contact:

Re: Onan Generator

Post by Corsair » Tue Dec 01, 2015 4:22 pm

The paperwork I received from the Mariner's Museum for a 1962 Constellation lists the Onan as the generators used in this era boat. It is larger than the listed optional wattage for the 45' but standard on the 55 and up size boats. The last two owners are assuring me it is an original installation. Their ownership spans 35 of the boat's 53 years - all at the same marina. My wife an I plan to start with week long cruises, and then graduate to longer ones as I phase out of the office. I realize that Onan was purchased by Caterpillar. I believe they now only make diesel units. I have googled for parts, but will now try dealers. I typically do my own maintenance, so still hope to find manuals and a parts list. Thanks for the input!!

User avatar
dag55
Posts: 70
Joined: Mon Dec 01, 2014 11:49 am
Contact:

Re: Onan Generator

Post by dag55 » Wed Dec 02, 2015 4:39 pm

Have You checked out Onan Parts? They have documentation and lot of good tips!!!
http://onanparts.com/
I'm shure they have Your impeller!
I have a Onan MCCK 4KVA in my -67 Cavalier 36' Seastrake. Haven't got it running yet, since the fuel pump seems to be fault..
It does start and run a little when given some gas into the carb though.
Cavalier 36' Seastrake 1967 "CillaGreta III"
http://chris-craft.org/registry/viewboa ... at_id=2318

jfrprops
Posts: 2092
Joined: Thu Dec 29, 2005 10:41 pm
Location: Powhatan Courthouse Virginia
Contact:

Re: Onan Generator

Post by jfrprops » Thu Dec 03, 2015 10:43 am

you guys need to be very careful with those , or any, old generators....dangerous things. Gas leaks, carbon mono leaks, electrical malfunctions/shocks. Just sayin......

John in Va
1980 Fairchild Scout 30
19?? custom Argentine Runabout 16'
1954 Whirlwind deluxe dual ckpt 16'
1921 Old Town Charles River 17' (founding Captain, James River Batteau Festival)

User avatar
Corsair
Posts: 37
Joined: Thu Nov 12, 2015 11:18 am
Contact:

Re: Onan Generator

Post by Corsair » Thu Dec 03, 2015 10:46 pm

Hey now, jfrprops, your sounding like a description I once overheard as my wife was discussing me!
Thanks for the web address dag55, I'll follow up.

jfrprops
Posts: 2092
Joined: Thu Dec 29, 2005 10:41 pm
Location: Powhatan Courthouse Virginia
Contact:

Re: Onan Generator

Post by jfrprops » Fri Dec 04, 2015 9:04 am

yeah Corsair.....I can understand that....but being old and single I would find a wife more dangerous than an ancient onan!

John in Va.
1980 Fairchild Scout 30
19?? custom Argentine Runabout 16'
1954 Whirlwind deluxe dual ckpt 16'
1921 Old Town Charles River 17' (founding Captain, James River Batteau Festival)

jim g
Posts: 1003
Joined: Wed Dec 14, 2011 10:55 pm
Contact:

Re: Onan Generator

Post by jim g » Fri Dec 04, 2015 11:57 am

jfrprops wrote:you guys need to be very careful with those , or any, old generators....dangerous things. Gas leaks, carbon mono leaks, electrical malfunctions/shocks. Just sayin......

John in Va
I agree with John.

About 12 years ago a couple was found dead on their late 60's 35' commander. The cruiser was at anchor. Their was due to carbon monoxide poison.

The bottom of the original steel Onan water lift muffler was rusted out. This was on a fresh water lake in Tennessee. It was summer and they had the generator running to run the a/c.

About 2 years after that I was asked to rebuild a 427 engine and do some general maintenance in a 35' commander of the same vintage. They didn't want me to do anything with the generator as a new westerbeake had been installed 2 years ago. When I looked around in the boat it still had the original steel Onan water lift muffler installed. I unscrewed it from the hull and poked my finger right through the bottom.

The owners of the boat were very happy that I took the time to check over all the systems of their boat.

joanroy
Posts: 686
Joined: Sun Jan 29, 2012 1:46 pm
Contact:

Re: Onan Generator

Post by joanroy » Fri Dec 04, 2015 5:57 pm

True. They can be dangerous if not well maintained, but that's true of every mechanical system on a boat, especially if it involves gasoline. My generator has a fiberglass lift muffler and is connected to new a new fuel system. I also have a hard wired marine carbon monoxide detector and a gasoline fume sniffer and I still always open the bilge and smell for fumes before I start up. I'm pretty confident my generator is safe, but I'm taking it out. Don't need it.

jfrprops
Posts: 2092
Joined: Thu Dec 29, 2005 10:41 pm
Location: Powhatan Courthouse Virginia
Contact:

Re: Onan Generator

Post by jfrprops » Sat Dec 05, 2015 2:24 pm

and I think the "taking it out because....don't need it...as joanroy says is the way we live today.....all that Winnebago stuff was all the rage back in the day.....we are passed that and the oldest of those components are dangerous.

John in Va.
1980 Fairchild Scout 30
19?? custom Argentine Runabout 16'
1954 Whirlwind deluxe dual ckpt 16'
1921 Old Town Charles River 17' (founding Captain, James River Batteau Festival)

User avatar
Corsair
Posts: 37
Joined: Thu Nov 12, 2015 11:18 am
Contact:

Re: Onan Generator

Post by Corsair » Tue Dec 22, 2015 10:43 pm

Well, here’s the deal. Life is full of compromises. Compromise 1: My lovely spouse who approved the boat purchase wants; her electric “stuff”, to cook on the electric stove top, to take a shower in hot water provided by the electric hot water heater, etc. So, rule one: Give her lots of electricity! Compromise 2: I’d like to maintain the boat with a goal of “factory and era correct”. I also want it SAFE. So, the vintage Onan stays, but a new non-ferrous “modern” exhaust system will have to be installed. Hey, with 10KW I can power up the marina if the lights go out. I understand Cummings bought out Onan, so I’ll contact them for the parts.

jfrprops
Posts: 2092
Joined: Thu Dec 29, 2005 10:41 pm
Location: Powhatan Courthouse Virginia
Contact:

Re: Onan Generator

Post by jfrprops » Wed Dec 23, 2015 2:29 pm

Understand Mark but doesn't change the facts of the case.

That stuff is OLD.

I just finished removing the frid, propane system, old charger, and hot water heater from my 1979 vintage boat.....I would not trust any of that stuff not to cause me more trouble than it is worth....that said...I am happily single and going boating?

do the prudent upgrades and get some modern detectors and do that same!

Merry Christmas

John in Va.
1980 Fairchild Scout 30
19?? custom Argentine Runabout 16'
1954 Whirlwind deluxe dual ckpt 16'
1921 Old Town Charles River 17' (founding Captain, James River Batteau Festival)

User avatar
Corsair
Posts: 37
Joined: Thu Nov 12, 2015 11:18 am
Contact:

Re: Onan Generator

Post by Corsair » Tue Jan 12, 2016 10:55 pm

John:
Thanks for your concern and advice. Thankfully there is a new hot water heater and other such items in the boat. The generator however seems to be original. I have significant experience in another asylum called antique cars. I love old mechanical things and restore them completely, then run the heck out of them. I'm confident I can restore the generator and fabricate a safe stainless steel exhaust system that has the appearance of the original, but is safe. My newest old car is a 1929 and the eldest a 1912. I restored a '28 and then ran it in the Great Race coast to coast three times. I still drive it regularly. I will be installing all the safety sensors and detectors in the boat this spring. OLD is relative, and not necessarily bad.

jfrprops
Posts: 2092
Joined: Thu Dec 29, 2005 10:41 pm
Location: Powhatan Courthouse Virginia
Contact:

Re: Onan Generator

Post by jfrprops » Wed Jan 13, 2016 10:08 am

yeah Mark, the old car nut house is where I started as well. Got so I didn't want any more black grease and crud under my fingernails......moved to boats....lateral move .......
Just be careful and I agree that old onan can be saved and used......get the dectectors.....

John in Va.
1980 Fairchild Scout 30
19?? custom Argentine Runabout 16'
1954 Whirlwind deluxe dual ckpt 16'
1921 Old Town Charles River 17' (founding Captain, James River Batteau Festival)

User avatar
evansjw44
Posts: 1865
Joined: Wed Jul 05, 2006 8:46 am
Location: Grosse Pointe Farms, MI
Contact:

Re: Onan Generator

Post by evansjw44 » Wed Jan 13, 2016 11:24 am

I'm very familiar with generators. The Onan 10KW is probably an odd ball four cylinder Onan engine. They made it both water and air cooled. The difference being the cylinders which are cast in pairs sort of like a motorcycle or an early car engine. If its not stuck getting it running should not be a big deal. I don't remember if it has a separate starter or if it used extra windings on the generator for starting like my Kohler. The Onan "Aqualift" mufflers are notorious for rusting out in the bottom leaving an exhaust leak. Best to put in a new fibergalss muffler. I'd replace the hoses too. My generator has a copper pip exhaust system.

If I can help give me a ring.

As for the 431 Lincolns, at 1600 hours they're getting tired if those are cruising spped hours. You don't want to hurt one. They're expensive to rebuild and tough to replace. Most of them have been replaced with 454 Mercs or Crusaders by now.
Jim Evans

Peter M Jardine
Posts: 697
Joined: Sun Mar 18, 2012 10:27 am
Contact:

Re: Onan Generator

Post by Peter M Jardine » Wed Jan 13, 2016 1:13 pm

I am intimately familiar with 431 Lincolns, and everything said in the previous post is true. They are pretty tough, but rebuilds are more expensive, marine gaskets are much harder to find. Keep in mind 1600 hours marine use is a LOT of use for a gas engine. Good luck with everything, nice boat.

User avatar
Corsair
Posts: 37
Joined: Thu Nov 12, 2015 11:18 am
Contact:

Re: Onan Generator

Post by Corsair » Wed Jan 13, 2016 3:53 pm

We have a great machine shop locally that rebuilds a wide variety of engines including most of the sprint car motors in our area. They are familiar with the 431's and have done a few of the marine variety. Rebuild cost is relative. Probably 2 1/2 time the cost of a small bock Chev and far less than 1/3 the cost of a 1912 Stearns. I'm good on 431 parts and castings with the 3 spare engines I have accumulated. I'll scope the existing motors in the spring and make a decision on rebuilds then. Former owner says they run strong.

Post Reply

Who is online

Users browsing this forum: Google [Bot] and 18 guests