'83...? ONAN diesel genset startup project.

[bix]

So the story is when I bought the property here the previous owners grew quite a bit of dope and im assuming either had a falling out or 5-6 years at a location was long enough to make it a tad suspicious and they left. Either way i used a bunch of sea cans and other junk on the property as leverage to knock 50k off the asking price as i couldnt afford the asking price. It worked, he accepted the offer on the grounds that removing all the cans ect.. would cost him roughly 15K.. Me being a crane operator means it wouldnt even cost over 2-3 to remove them myself but either way doesnt matter. What does matter is what i found in one of the "containers". The PO had run 110v panels into all of the containers so he never even fired this up. When i spoke to the PO about the generator he said " Oh yea, that came with the container.. never used it but the guy i bought it from said it has 37 hours on it ".

Ive been having a hard time finding any parts available since Cummins bought ONAN back in the early nineties it seems. Id love to crank a battery onto this thing and turn it over as i know it spins and the head looks mint under the valve covers.. break in instructions are still zip tied to the thing, the oil seems fine... My worries are that :

A: i have no idea how generators are normally wired..
B: i dont know anything about diesels except they dont have spark
C: how do you prevent a runaway situation before it occurs worst case?
D: if i get this thing running is it just going to produce 10K watts out of the cut electrical cables and potentially zap myself or something else bad, 10-12K watts can do...


My goals for this gen set are:

-Rig up a simple oil pressure gauge
-Start/stop button
-Maybe drill or tap a coolan sensor somewhere
-Im guessing i need to get a 12v switched source for the glow plugs, and a stop button.. which by logic must just cut off fuel.. so that might mechanically exist on this unit. I cant seem to find a control pannel/box or whatever id need as all parts are pretty rare.
- Dig a trench from the container to the house and install a transfer switch for back up power. The only city service im connected to is power, so id love to have power when it goes out, which this winter was for days at a time...

If anyone diesel generator gurus out there would know how to wire this thing up.. i dont mind messing around with electricity but this amount of power does make me a little nervous, because getting shocked by a coil can be enough to set ya straight... so im not jumping at this until im confident and have the best information on this generator ass possible. I contacted the closest cummings diesel generator tech i could find, but nothing really came of it when he said he would look for a control panel months and months back...


I think the fact that the engine mounts are just Right hand IWRC wire, coiled up to support the motor makes my inner " wire rope " dork quite happy










@Bent77
@tRustyK5 Not sure where this thread belongs.... feel free to move it wherever it belongs best.

 

[bix]

 

[TreeFarm]

I have circled some stuff for you.

RED is the stop solenoid. This is spring loaded the off position and takes 12v to pull it to the Run position. This is what tells the injection pump to supply fuel or not to allow the engine to run.

Black looks like the throttle. May have a manual control or be straight governed to a set rpm.

Yellow is the injection pump. Think of it like a distributor only it sends fuel instead of spark. The 4 fuel lines running off of that face go to the injectors. There will be a fuel in from the filters and a return back to the tank off of that. There will also be a return from the injectors T'd into the return line on top.

Green is your lift pump and a glass sediment bowl. Feeds the fuel filters and then the injection pump.


How to prevent run away. For this guy I dont know. But how to stop it once it starts is to cut off air supply. So have a piece of wood ready to cover the air intake in case it does run away. Not likely though, its not that common of a thing.

Thing you need to know about diesels is that fuel is everything. Not necessarily quality of fuel. whats in the tank will probably run fine. But you cant have any air in the system. IF you open up one of those filters, you better re fill it before you put it on. Then you will still have to bleed it. I would try to start it first, and then bleed it if it doesn't start. If nothing is broken, it shouldn't have lost its prime. If it does need to be bled. Start at the top of the filters. then crack the nuts loose on the injectors and crank until fuel comes out. once fuel comes out of one, tighten it and keep going until they all have fuel or until it starts.

On the generator side of things, it gets complicated and Ill leave that to experts. It probably wont output power though without something to excite the field. I dont see any control boxes or panels in the pictures.

 

[bix]

Ive decoded to the best of my abilities the following

15.ORDJC=3CR/1AD

15.0 is the approx wattage, RD is rad cooled, J is the engine series, C is 4 cylinder @ 3.25" bore. 3CR is 120/240 Vac 1 ph 4 Wire..

k830685512E

k is 11th month and 83 is the year, the rest is the serial number.

 

[bix]

I have circled some stuff for you.

RED is the stop solenoid. This is spring loaded the off position and takes 12v to pull it to the Run position. This is what tells the injection pump to supply fuel or not to allow the engine to run.

Black looks like the throttle. May have a manual control or be straight governed to a set rpm.

Yellow is the injection pump. Think of it like a distributor only it sends fuel instead of spark. The 4 fuel lines running off of that face go to the injectors. There will be a fuel in from the filters and a return back to the tank off of that. There will also be a return from the injectors T'd into the return line on top.

Green is your lift pump and a glass sediment bowl. Feeds the fuel filters and then the injection pump.


How to prevent run away. For this guy I dont know. But how to stop it once it starts is to cut off air supply. So have a piece of wood ready to cover the air intake in case it does run away. Not likely though, its not that common of a thing.

Thing you need to know about diesels is that fuel is everything. Not necessarily quality of fuel. whats in the tank will probably run fine. But you cant have any air in the system. IF you open up one of those filters, you better re fill it before you put it on. Then you will still have to bleed it. I would try to start it first, and then bleed it if it doesn't start. If nothing is broken, it shouldn't have lost its prime. If it does need to be bled. Start at the top of the filters. then crack the nuts loose on the injectors and crank until fuel comes out. once fuel comes out of one, tighten it and keep going until they all have fuel or until it starts.

On the generator side of things, it gets complicated and Ill leave that to experts. It probably wont output power though without something to excite the field. I dont see any control boxes or panels in the pictures.

View attachment 373575

Thanks! thats a huge help. I know run aways arent common at all, but ive definitely searched it on youtube and seen what can happen and it looks violent haha! ill have something handy to cut off air if need be.

 

[Bent77]

Here’s a couple resources. These should be all in Canada. Give them the serial and see if they can answer more questions. I’d call, not email

Onan Parts.Com, Rebuild Parts for Onan engines

Onan Parts Engines, Internal rebuild parts, Pistons, Rods, Bearings, Gaskets and more.

www.onanparts.com

Cummins Canada Online Store - Free Shipping on orders of $200 or more

Shop online for Fleetguard Filters & Coolant, Valvoline Oil, Webasto Heaters, and many more products. Get Free shipping on qualifying orders of $200 or more.

shopcummins.ca

Not Canada

Onan Parts at Jack's

Find all the Onan Parts and Accessories you need, with fast shipping and low prices!

www.jackssmallengines.com

 

[bix]

@Bent77 thanks for more rabbit holes to go down! . Im making progress though which is good.

 

[tRustyK5]

My generator knowledge is not the best, but I did work at a place that built them a long time ago. In order to produce clean 60 hz power the governor is set to a multiple of 60 that is within the engines operating range. The most common for diesel generators of that size is 1800 rpm. Small gas engine generators most often run at 3600 under load. We also did a few where noise was a big concern that were set up to run at 1200 rpm.

With a "G" governor they either run idle, or 1800 rpm.

The wiring side of things was not my area, although I kinda wish I had poked around a learned a few things there. I mostly built the skids, enclosures, extended sump systems etc and once in a while helped with the set-up for load testing. The vast majority of stuff we built was JD for the bigger stuff, and Kubota for the smaller stuff like light towers.

Runaways are only a real likelihood if you have been into the governor and re-assemble it wrong. A piece of plywood capable of covering the air intake will be good insurance. I did see a 250KW prime power gen set run away...it was spectacular! That engine came in with a regular governor and I think they attempted to convert it somehow? I don't recall the specifics, other than they messed with the governor and F'd it up. That thing fired and went to the moon...

 

[Fordum]

When I first saw the title, I thought I might be able to help. I've got a 70's model Onan genset that I ran for backup for years. But mine is not much like yours.
Its a 100KW, with a 6 cylinder turbocharged Allis Chalmers engine with an electric lift pump. Mine turns off by killing power to the fuel pump.
I'm not all that knowledgeable about diesels, know a little bit more about the generator side. As mentioned, it has to run at a multiple of 60 cycles per second to make correct frequency power. Yours is rated to run at 1800.
Big ones like mine are mostly all set to start up and stay at full speed.
I have seen some smaller ones, like welding generators, that will idle down and speed up when they see an electrical load.

As to whether it will make power as is, depends on what type of generator it is. If its a brush type, then it needs some kind of external power. Probably from the battery.
But, if its a brushless, then it can start producing power right away from the residual magnetism in the secondary rotor. Mine does so, but there is a procedure for supplying a quick flash using a 9 volt battery and a diode. I've never had to do it, and I think unless you have replaced the rotor, its unlikely to need it.
I had good luck with finding pretty much the complete set of manuals for mine from Onan. And I think I they may still be available from Cummins.
A lot of those units were very well built, and many were used as standby, so there are lots and lots of them still out there.

About the only thing I might help with, is that it looks like there is a priming lever on the side of the fuel pump. Hard to say from the picture.
If so, it is kind of a necessary exercise in futility. Each stroke of the lever produces a tiny amount of fuel. So it take a lot of strokes to get something done.
But, if you have air between the pump and the injector pump, such as when you change fuel filters, its much better to use that lever than cranking the engine to fill up the lines.

I'm sure you know this, but here goes: Those type diesels produce high fuel pressure inside the injector pump. As the engine rotates, the injector pump supplies a shot of high pressure fuel to each injector at the correct time exactly like a distributor does to spark plugs. This high pressure forces the injector to open and spray in the fuel.
Since liquids are not compressible, its like a solid rod forcing the injector open.
Even the tiniest air bubble in the line between the injector pump and injector will compress and absorb the pressure needed to open the injector causing that cylinder to not get fuel.

So, air anywhere in the fuel system is not good. But its worse from the injector pump on.
So, if you have air between the lift pump and the injector pump, its best to pump it out with the lever. If you crank the engine, the air may get into the injector pump, and then you have to loosen each injector line while cranking to get the air out of that side.
One of the first things to do, is to invest in a good tubing type wrench that will fit the nuts on the injector lines and tie it close to the generator. You do not want to round those nuts off. And trying to find the wrench while the power is off at night during a storm is not fun.
I'll bet that bolt on top of the two fuel filters is the air bleed. If you change the filters, fill them up as full as you can off the machine. Screw them on and loosen the top bolts. Pump the lever until nothing but fuel comes out the top.
Then go to the fitting right at the injector pump and loosen it. Pump the lever and make sure no air comes out.

Of course, there are folks here who make their living keeping diesels running, I just dabble. Plus I'm in the middle of turkey hunting, so all information I give is suspect.

 

[Fordum]

OK looks like this should be the manual for your engine.
Found it here: https://greenmountaingenerators.com/manuals-and-support/onan-service-and-parts-manuals/
Also ran across this site that seems to have lots of Onan genset info on it.

Onan Generators

Restoring, operating, and maintaining vintage Onan generators. When asking questions about your generator, give your model number AND serial number.

www.smokstak.com

Might register with this site. Its the official site for your make genset, and they may have everything you need.

Cummins QuickServe Online

Cummins QuickServe Online. The complete source of parts and service information for over 11 million Cummins diesel engines and Cummins Power Generation products.

quickserve.cummins.com

Hope this helps

 

[bix]

My generator knowledge is not the best, but I did work at a place that built them a long time ago. In order to produce clean 60 hz power the governor is set to a multiple of 60 that is within the engines operating range. The most common for diesel generators of that size is 1800 rpm. Small gas engine generators most often run at 3600 under load. We also did a few where noise was a big concern that were set up to run at 1200 rpm.

With a "G" governor they either run idle, or 1800 rpm.

The wiring side of things was not my area, although I kinda wish I had poked around a learned a few things there. I mostly built the skids, enclosures, extended sump systems etc and once in a while helped with the set-up for load testing. The vast majority of stuff we built was JD for the bigger stuff, and Kubota for the smaller stuff like light towers.

Runaways are only a real likelihood if you have been into the governor and re-assemble it wrong. A piece of plywood capable of covering the air intake will be good insurance. I did see a 250KW prime power gen set run away...it was spectacular! That engine came in with a regular governor and I think they attempted to convert it somehow? I don't recall the specifics, other than they messed with the governor and F'd it up. That thing fired and went to the moon...

When I first saw the title, I thought I might be able to help. I've got a 70's model Onan genset that I ran for backup for years. But mine is not much like yours.
Its a 100KW, with a 6 cylinder turbocharged Allis Chalmers engine with an electric lift pump. Mine turns off by killing power to the fuel pump.
I'm not all that knowledgeable about diesels, know a little bit more about the generator side. As mentioned, it has to run at a multiple of 60 cycles per second to make correct frequency power. Yours is rated to run at 1800.
Big ones like mine are mostly all set to start up and stay at full speed.
I have seen some smaller ones, like welding generators, that will idle down and speed up when they see an electrical load.

As to whether it will make power as is, depends on what type of generator it is. If its a brush type, then it needs some kind of external power. Probably from the battery.
But, if its a brushless, then it can start producing power right away from the residual magnetism in the secondary rotor. Mine does so, but there is a procedure for supplying a quick flash using a 9 volt battery and a diode. I've never had to do it, and I think unless you have replaced the rotor, its unlikely to need it.
I had good luck with finding pretty much the complete set of manuals for mine from Onan. And I think I they may still be available from Cummins.
A lot of those units were very well built, and many were used as standby, so there are lots and lots of them still out there.

About the only thing I might help with, is that it looks like there is a priming lever on the side of the fuel pump. Hard to say from the picture.
If so, it is kind of a necessary exercise in futility. Each stroke of the lever produces a tiny amount of fuel. So it take a lot of strokes to get something done.
But, if you have air between the pump and the injector pump, such as when you change fuel filters, its much better to use that lever than cranking the engine to fill up the lines.

I'm sure you know this, but here goes: Those type diesels produce high fuel pressure inside the injector pump. As the engine rotates, the injector pump supplies a shot of high pressure fuel to each injector at the correct time exactly like a distributor does to spark plugs. This high pressure forces the injector to open and spray in the fuel.
Since liquids are not compressible, its like a solid rod forcing the injector open.
Even the tiniest air bubble in the line between the injector pump and injector will compress and absorb the pressure needed to open the injector causing that cylinder to not get fuel.

So, air anywhere in the fuel system is not good. But its worse from the injector pump on.
So, if you have air between the lift pump and the injector pump, its best to pump it out with the lever. If you crank the engine, the air may get into the injector pump, and then you have to loosen each injector line while cranking to get the air out of that side.
One of the first things to do, is to invest in a good tubing type wrench that will fit the nuts on the injector lines and tie it close to the generator. You do not want to round those nuts off. And trying to find the wrench while the power is off at night during a storm is not fun.
I'll bet that bolt on top of the two fuel filters is the air bleed. If you change the filters, fill them up as full as you can off the machine. Screw them on and loosen the top bolts. Pump the lever until nothing but fuel comes out the top.
Then go to the fitting right at the injector pump and loosen it. Pump the lever and make sure no air comes out.

Of course, there are folks here who make their living keeping diesels running, I just dabble. Plus I'm in the middle of turkey hunting, so all information I give is suspect.

Thanks guys for the information you could throw my way. When ya dont know much, its hard not to learn anything! Found a forum called smokstak with a bunch of old onan boys on it which should be great. Still waiting on a moderator to accept my request.. but there seems to be some great information on them because it seems like there was such a demand for these units at a time that ONAN would make some " Bastardized " units in terms of electrical parts depending on what they had on the floor, So no gaurenteee the unit numbers are the same. Im hoping to print out the wiring diagrams and go out there n see whats really missing and do an inventory. I had primed the lines full one of the time i was messing around with it. Never got the filters off when i tried buuuut since they are original and never used, cant imagine theyd be too bad. The fuel smells like varnish but im sure thats normal. Id plan on filling up the tank with fresh diesel just to dilute it some before firing.


As for the runaway, thats neat you saw one. Seems violent ha... I figured to get this gen set running on its own oil, is far from where it sits doing absolutely nothing right now but figured it should be something to consider.

 

[TreeFarm]

Thanks guys for the information you could throw my way. When ya dont know much, its hard not to learn anything! Found a forum called smokstak with a bunch of old onan boys on it which should be great. Still waiting on a moderator to accept my request.. but there seems to be some great information on them because it seems like there was such a demand for these units at a time that ONAN would make some " Bastardized " units in terms of electrical parts depending on what they had on the floor, So no gaurenteee the unit numbers are the same. Im hoping to print out the wiring diagrams and go out there n see whats really missing and do an inventory. I had primed the lines full one of the time i was messing around with it. Never got the filters off when i tried buuuut since they are original and never used, cant imagine theyd be too bad. The fuel smells like varnish but im sure thats normal. Id plan on filling up the tank with fresh diesel just to dilute it some before firing.


As for the runaway, thats neat you saw one. Seems violent ha... I figured to get this gen set running on its own oil, is far from where it sits doing absolutely nothing right now but figured it should be something to consider.

Without a turbo there really is no way for it to run on its own oil unless it’s pulling it from the valve guides. The oil has to get into the intake before it can run on it.

Run away without oil would be from the injection pump sticking open at full fuel and the governor not being able to pull fuel and maintain a safe rpm.

 

[bix]

so what i should do is put a battery on this thing already...? I want to make a little gauge cluster for it. I have some spare gauges, will need a start button though. Itd be nice to find out if the starter works or not. Its located on the backside of the engine up against the wall so i havent even been able to lay eyes on it really. might have a spare battery laying around

 

[TreeFarm]

I’m guessing that It was originally wired with there being a coolant and oil pressure cut off switch as well as sender for gauges. So if it doesn’t have oil pressure or it’s hot it will cut power to the fuel solenoid.

Realistically for just getting it started. I would hook up a manual oil pressure gauge. A 12v source to the fuel solenoid to be your run/off and then a momentary switch for the starter. You can get generic ignition switches that have all those functions for a few bucks at a Napa. Or you could just vicegrip those wires to the battery post if you wanna see it run before investing money.

there is a chance that the 12v fuel solenoid has multiple circuits in it. Some have a pull circuit and a hold circuit. So you give temp 12v to pull it in, and then switched 12v to hold it In. But again. If you just want to see it run you can hold it in by hand

 

[bix]

Right on, I have the manual oil pressure gauge from the c10, as well as a manual coolant gauge as well. Ill work on adapting those two gauges and an ignition switch.

 

[Blue85]

D: if i get this thing running is it just going to produce 10K watts out of the cut electrical cables and potentially zap myself or something else bad, 10-12K watts can do...

No, without a load it delivers 0 power. Usually there's a breaker on the output and as long as it's open, the electrical side is safe. You'll want to remove any dangling wires before getting started. The output is as safe to work on as any 220V electric circuit is - don't touch while it's on. Of course when you get it running you'll want to measure the output voltage. If your meter reads frequency, you can use that to set the governor speed.

 

[JoshHefnerX]

I just wanted to get in here to say I was jealous... lol

Nice generator in the makings there dude!

 

[warrpath4x4]

I can help you out with looking up parts that originally came on it, I've attached the parts manual for you. when looking at a part that lists multiple "spec" letters, yours is a spec E

 

[Fordum]

Much later, if it works well, and you decide to keep it, you might consider replacing the mechanical fuel pump with a small low pressure electric one.
My big genset uses an electric one instead of an engine driven one from the factory. Not only does it make bleeding air from the lines and refilling fuel filters easy, but when you turn off the power to it, the genset dies, because it gets no fuel without that pump running.

 

[bix]

No, without a load it delivers 0 power. Usually there's a breaker on the output and as long as it's open, the electrical side is safe. You'll want to remove any dangling wires before getting started. The output is as safe to work on as any 220V electric circuit is - don't touch while it's on. Of course when you get it running you'll want to measure the output voltage. If your meter reads frequency, you can use that to set the governor speed.

ok thanks for confirming that. Im going to try and hunt down a breaker and look at the wiring mess closely for the first time,

I just wanted to get in here to say I was jealous... lol

Nice generator in the makings there dude!

thanks dude, its far from powering up the house but its a start!

I can help you out with looking up parts that originally came on it, I've attached the parts manual for you. when looking at a part that lists multiple "spec" letters, yours is a spec E

That manual is awesome thanks. ive been sifting through many cummins manuals from their site but that was the one. It helps me visualize the control panel and what is all missing.