Onan CCK won't crank

[Joe Stewart]

4.0CCK-3CR/12017R 0375931504

Sorry if this topic has been rehashed in the past. I did a search, but did not come up with any good leads.

I bought this machine a few years ago. After I bought it, as I recall, I hooked up a battery to it and cranked it over for a few revolutions. I wasn't getting any spark at that time, so I got frustrated and stowed the machine in a corner of the garage and let it sit until now.

I took it out this morning and hooked up a fresh battery to it, but when I hit the "start" button, nothing happens (no clicks, no noises, no attempt at turning, nothing).

I removed the heavy positive battery lead to the solenoid and placed it directly onto the opposite terminal on the solenoid. It cranked over great when I did this.

So I'm trying to figure out why it won't crank using the "start" button.

I noticed that I have power to two (2) of those terminals on the (left) inside of the control box (but not the rest). See photo. I furthermore notice that there is power to one of the terminals on the coil (but not the other) and that the coil got a little warm while I had the power lead connected to the positive side of the battery.

I also noticed that there are two fuses inside plastic sleeves. The fuses "appear" to be good.

I'd love to get this machine generating.

Any ideas welcome. J. Stewart

[Jim Rankin]

coil gets hot because the ignition breaker points are closed. That grounds out the voltage that comes through the coil primary circuit from the ignition switch. To confirm that, rotate the engine and see if you don't get voltage on both sides of the coil as the points open. Coil could be bad as well.

Why it won't crank over,
Could just have a bad solenoid. Did you attempt to jumper the solenoid control terminals before you bypassed the thing all together?

By touching the battery cable to the starter terminal, you found the starter is good, but you don't know if the solenoid is bad or it's just not getting the right signal from the control. I don't know if that start signal is grounding a terminal on the solenoid or sending B+ to it. Someone who knows will be along shortly.

[derone]

Hey that looks alot like mine used to... Grounding the start wire on the solenoid should cause it to crank. That wire goes to terminal 3 on the control board. On the backside of board cover is the schematic. K1 is the start solenoid, S1 is the starter switch, terminal 1 is the ground for the center pin on the starter switch. Hope this helps.

Disregard my post above...I was looking at the wrong schematic.

[Lawdawg]

Joe
I looked at Pic #2 very hard it appears to have been worked on before in between the two switches there is a 1/4 watt resistor that has been Jumpered with another resistor so I suspect after you completely trouble shoot the Control Board it will most likely be the major problem. that is what was wrong with my Unit after I bought a new board all was well and the old Onan came back to life. You can Jump the Control Circuit out to test the engine by running a wire from the Batt Positive to the + side of the spark coil and jump the starting Solenoid to see if the engine will run but remember when you do this you have no saftey devices to protect the engine so do not run it long wired this way. Doug.

[bobbyz72]

Throw the board in the trash, you dont need it unless you plan on reinstalling in a motorhome.

[allis327]

My switch is going bad on my control board and I was going to replace board but if I could eliminate it that would be great. How do you do that.

[bobbyz72]

Hmm, i did a step by step post, i will look later and see if i can find it. Ive talked several people here through it, they mostly understood it 100% from the post, just wanted to dubble check stuff. Since the post we have changed a thing or two..

[lijobi]

I agree, the board is a piece of junk. I paid around $150 for a Flight Systems replacement board and it was plug and play. The new board retains all of the battery charging and shut down systems and is well worth the money on an otherwise good machine. You can bypass the board as bobbyz72 says, but being able to charge its own starting battery is a good thing. To test the unit you can clip an ohmmeter on the oil pressure sender to verify pressure while running, and run 12 volts directly to the coil to keep it running. You've already figured out how to make it crank, 12 volts to the fuel pump and you're golden... Run that sucker and test it good and then decide what all you want to do then.

[bobbyz72]

If you want it as simple as you can get it.... start reading from post #12.... http://www.smokstak.com/forum/showthread.php?t=70922 You can also add a relay, so that if the generator runs out of gas, it will take power off the coil so it does not get hot if left sitting for hours with the points closed. All you have to do is wire the relay to the oil pressure switch, so that when the oil pressure builds, its but a ground on the relay, and relay closes putting 12+ to the coil. When engine runs out of gas... or runs low on oil.. or what ever... oil pressure drops, and relay opens, removing 12+ from coil,, engine stops.

[Joe Stewart]

OK, thanks for the replies. I had some time today to look at it again. I jump started the solenoid directly from the positive terminal of the battery and the solenoid is good (motor turned over). So I think my problem lies in the starter switch (which apparently is a PART of the circuit board). Or perhaps there is no juice actually getting to the switch - I guess this could still be a problem with the circuit board. The only terminals on the left side of photo #2 that have juice are the one with the heavy yellow plastic insulation and the one right below that one. The next thing I will try to do is bypass the safety devices and see if I can get the motor to run and see if the generator produces electricity. If it runs, I will buy a flight systems board. Thanks for all input and any other suggestions will be welcome. J. Stewart.

[derone]

The control board may be ok. I'd label all of the wires and remove them at the terminal blocks, then remove the board. Find some 'purple power' spray cleaner and an old toothbrush. Put the board in a sink, spray it completely w/cleaner, brush it down, rinse with hot water, then blow it dry with a hair dryer or compressed air. Make sure it's completely dry b4 reinstalling and try again...

[Darxen]

I have worked in Electronics for years, and find, in cleaning PC cards,,etc, the best thing to use is "Rubbing Alcohol" ! I normally use a small 1 inch paint brush, or an "acid brush" those ones with a silver metal handle and short black bristles. I will dip the brush into the Alcohol,,then clean the board with a wet alcohol brush, basically scrub it with the brush, then I will blow dry it with a hair dryer, set on medium or high. Alcohol evaporates quickly, and will also allow the water component to evaporate as the alcohol does. Water by itself and some soaps, can actually conduct electricity, and cause problems..Your board does look dirty, but I think using Denatured Alcohol and a small paint brush will do fine,,and be safe. Usually a bottle of alcohol cost abut a buck..Denatured Alcohol will take of any protective coatings,,so I would stay with the rubbing alcohol. Also, you can blow dry it, but you have to be carefull not to blow it up inside a relay, etc..a gentle blowing is good,,but a hair dryer works great..the smell of the evaporating alcohol smells kind of good also !! Sometimes I have cleaned boards 5 or 10 times like this !!

[George Clark]

you probably have a bad transistor on the board or a stsrt solenoid cant tell you will have to test for thet, control boards may still be available from flight systems dont know, if you send me an email with thye model and spec number of your unit I will send you the manuals and diagrams for that unit,georgenfw@hotmail.com

[derone]

Originally Posted by Darxen

I have worked in Electronics for years, and find, in cleaning PC cards,,etc, the best thing to use is "Rubbing Alcohol" !!!

I guess when we were turning out 11 to 1400 repaired PC boards a month we didn't know what we were doing, eh? Rubbing alcohol is 'safe' but not cost effective since it evaporates quickly and doesn't really lift dirt and grime. We repaired every major line of cash register and printers and you could only imagine what the insides looked like if they were housed in a restaurant's kitchen. We never had a single failure due to a bad washing...now if you don't dry it completely, that's your fault. On another note, I sprayed my
300-0859 board w/clearcoat(except the TO-3 pair) after it tested out ok, for some additional water/moisure resistance.

[bbuchorn]

Sorry to see you havin troubles with your rig, But if the pics you posted are of what you are tryin to run, and all you are lookin at is the electrical part,Maybe you should look at the motor end and note that you are missing one cylinder head and that cylinder don't look real healthy. Good luck on gettin it to run , but you need a cylinder head and the metal shroud that goes over it for proper cooling. Check your mechanical end first (engine) and make sure it is ready to run, then check out the generator end. Good luck. BB