Onan 4000 still won't start from remote

[Scoundrel]

I replaced the house batteries because they were faulty. I assumed at this point that was the reason the Gen wouldn't start from the remote switch. It starts great from the main switch on the gen without hesitation. However when trying to start it from the remote it turns over for about 10 seconds and then dies. In addition when I get it started from outside and attempt to shut it down from the remote switch is nearly stops but not quite and then starts to misfire and blow black smoke from the exhaust.

Suggestions?   
   

 

[Gary RV_Wizard]

This is a fairly common complaint but bases on what I've heard it seems to have a variety of causes.  Perhaps the relay for the remote switch is faulty or has corroded connections. Check wiring at both the remote switch and where the remote connects to the genset. And check voltage at both points.

As for stopping, it sounds as though the genset may begin running in reverse after "almost stopping" or perhaps is just getting intermittent ignition. Again, the remote's relay could be the problem if it does not fully disengage.

Are these symptoms exactly the same as before you replaced the batteries or was there a change after replacement.

 

[Scoundrel]

Gary,

Nothing has changed other then now it attempts to start where before the batteries were changed it didn't even try, unless of course the engine was running. The relay you speak of is where...? I will check out the remote switch and see if there is any visible signs of corrosion. I'll have to do some searching to find where the wiring from the remote switch connects to the genset. I'll get back to you with what ever I find. 

 

[fredethomas]

Past problems of this nature have been caused by a faulty ground of the remote switch.  I do not know where the ground point is however.

The starting of the genset should by rights be done by the chassis battery - not the coach batteries.  It is the coach batteries that get run down and the proper voltage might not be there to make the start.  The chassis battery should always be high enough to start it.  My Heart Inverter monitor shows the chassis battery does the starting.  The voltage drops to 11.65 as the genset starter switch is depressed.

Your problems sounds like an intermittent ground on the switch.

 

[Gary RV_Wizard]

Both of your starter switches (remote and the oneon the genset) are basically just switches that close a relay which provides power to the starter motor. I would think the relay would be on the genset and close to the starter itself, but it is conceivable it is near the battery instead. Follow the wires from the starter motor to the relay.

AS Fred says, a poor (corroded) ground is a common cause of the symptoms you have, but so is a corroded "hot" wire from the battery.

 

[Scoundrel]

I pulled the remote switch from the dash and the switch as well as the wires look good. In fact the price tag is still like new on the switch which leads me to believe the past owner was trying to find the same problem.

I took a look at the Genset and all I could see in the way of wires was a 6 wire plug that plugs into a box on the side of the Genset. I pulled the plug to see if it looked corroded but it appeared to be fine. There was a single brown wire that came from the same box and wrapped around to the back of the Genset. I have no idea what it was for but it was much to small a gage wire to be used for starting the Genset. There is one large cable coming from behind the Genset and grounds to the frame just in front of the Genset door. I will remove it tomorrow and see if it is grounding properly.

I don't have a multimeter, nor do I know how to use one so I can't chase down electrical shorts or check voltage. 

I feel like a dog chasing his tail........ :-\

 

[Gary RV_Wizard]

That six wire plug may contain the wires coming from the remote. Sounds like the brown wire goes to the starter solenoid, which  is yet another relay that actually engages the starter. That presumably is OK, since the local genset starter switch works fine.  Do some of the wires in that plug go off toward the front of the rig (or wherever the remote start switch is)?

Yeah, sounds like somebody already replaced the remote to try to solve the problem.

Since you aren't skilled with electrical measurements and diagnosis, you may need a genset technician to resolve it. If it's an Onan there is probably an authorized shop in your area, often associated with a Cummins engine dealer/shop.

 

[Scoundrel]

Yes Gary it is a Onan 4000. I will look closely at where the six wires go. I do know they don't all head the same direction but I didn't look close enough to follow where they are going. I will do that. I'll unplug the brown wire and see if it can be started from the switch on the Genset. If it is to the starter solenoid obviously it will not start.

If I can't find anything obvious I will take it to the local dealer and have them look at it. By the way since I don't have any manuals is the oil filter the same as those used on cars or light truck? Is there a cross reference part number for an off the shelf oil filter? and lastly do you use automotive grade oil such as 10-30 weight in the Genset or is there a special oil?

Thanks for your peitence....

 

[Gary RV_Wizard]

Here is one source for Onan manuals and parts (including filters) - I think they charge $12 for a downloadable manual. Maybe some other 4000 owner woud copy or scan the important pages of his and send it to you for less.  I have a Generac, so can't help.

If you know the Onan filter number, most autoparts stores can cross-reference it to other brands. Wheher they stock the item is another question, but they should be able to get it for you easily.

I don't know what oil Onan recommends for the 4000 but 10W-30 or 5W -30 is pretty safe. Hopefully an Onan owner will contribute the correct info.

The Onan Store:  http://www.funroads.com/onanstore/osHome.jhtml

The Onan Store website also has info on locating Onan dealers/servicers and an "Onan Forum"

 

[Scoundrel]

Well the last of my big problems (hopefully) still has not gone away.

I removed the large ground cable in front of the Genset and cleaned away the rust and reattached it.

The switch looks new and has one red (hot) a brown that Y's off to the hrs. counter and a green and blue wire all of which are buried somewhere in all the wires under the dash. On the Genset there is a plug that has several white wires and two of which run to the left side of the genset and the remaining run to somewhere behind the genset where I can not see what they attach to.

Again I have no problem starting it from the outside switch on the genset but I won't start from the remote switch. When I push the button it sounds like the starter is turning over and the genset kind of bucks and grumbles then stops. It acts like the fuel pump is not working. Of course that's assuming it is an electrical pump not mechanical. I don't know which because I have no manual that's anything more then just an operator manual. The manual says to refer to the manufacture of the coach for wiring details.

So I thought I'd bring this up again in hopes it will jog the memory of someone.....
 

 

[Karl]

Don,

The unit with the white wires coming out of it is a computer-type controller. Among other things, it monitors output voltage, overspeed, low oil (probably what the brown wire is for). If it's bad, that could very well account for things not working right. Question: when you press and hold the remote start switch and the engine tries to start, does the starter disengage or does it keep running? 

 

[Terry A. Brewer]

Don

The schematic I have shows 5 wires to the aux switch:

1(A) Batt ground
2(B) Stop output
3(C) Start/Preheat Output
5(E) Switched B+ From Genset...This is for HR. meter
6(F) Genset Status light.....This is for light indicating genset running, mine is on the switch itself.

I used this to hook up a auto-genstart.?

The above is for a gas/propane unit

 

[Scoundrel]

Don,

The unit with the white wires coming out of it is a computer-type controller. Among other things, it monitors output voltage, overspeed, low oil (probably what the brown wire is for). If it's bad, that could very well account for things not working right. Question: when you press and hold the remote start switch and the engine tries to start, does the starter disengage or does it keep running??

I believe the starter disengages. The reason I think so is if I continue to hold the button down after the initial start attempt nothing happens.

The brown wire Y's to the meter and then down the harness from the switch. 

 

[Scoundrel]

Don

The schematic I have shows 5 wires to the aux switch:

1(A) Batt ground
2(B) Stop output
3(C) Start/Preheat Output
5(E) Switched B+ From Genset...This is for HR. meter
6(F) Genset Status light.....This is for light indicating genset running, mine is on the switch itself.

I used this to hook up a auto-genstart.?

The above is for a gas/propane unit

I have no light indicating the genset is running....

If there is a disconnect between the switch and the genset why would the starter attempt to start and then disengage?

 

[gensetbill]

if you havent found out the reason for you starting failure check out my post to elway on his topic generator question. that might help if not e-mail me and we will figure it out, Im not sure where your at but if you cant get it and feel like a road trip im in medford oregon.  good luck

 

[Scoundrel]

if you havent found out the reason for you starting failure check out my post to elway on his topic generator question. that might help if not e-mail me and we will figure it out, Im not sure where your at but if you cant get it and feel like a road trip im in medford oregon.? good luck

I have yet to have a chance to look at it. I will be working on my dash A/C first and then tackle the Genset issue. I'll e-mail you as soon as I get started.

Thanks.. 

 

[gensetbill]

sorry scoundrel i referenced you to the wrong post it is the one that says  onan 6.5nhe. not the generator question sorry  anyway that sounds great ill be here whenever.  good luck  bill

 

[Karl]

Don,

The reason I asked about the starter disengaging was because I had a similar problem 2 years ago. My starter did not disengage, and it turned out to be one of the 'black box' genset controllers malfunctioning. Seeing as yours acts differently - well I just don't know. IIRC, we already eliminated fuel problems (fuel pump, pickup, carb), right?

 

[gensetbill]

ok scoundrel,
  If the genset starts and stops  from the main switch, and runs good .then the problem is with either the switch is shorting out or the wiring harness from the switch to the genset is shorted somewhere. Or the gauge of wire that is installed on the switch is not right.  The remote switch connects to the same  posts on the circuitry board as the main switch. so if the main works fine the problem has to be somewhere in the wiring harness,or the switch, some of the onan harnesses has a central connector in the middle of the harness. try jumping the start sequence with a wire rather than the remote switch. if it doesnt start correctly,then your problem is the harness,if it does then it is the switch  It is possibly not grounding correctly, If a ground is weak the current thru it will only engage then short, which is what it sounds like its doing keep us posted we will figure it out for you

 

[bidderwins]

I know this is a very old thread but I have the very same exact issues.Was this problem ever fixed and if so what was the cure. Thanks.