I think you've solved it correctly. Mine works this way too. Another way to phrase it so that it makes sense to everyone is, that while other engines seem to "run along" or "take" on their own once you kick things into motion, the Onan wants me to hold the button until the generator is running all the way (not really holding after it's started, just till it's started, which seems like a longer start phase than other engines). It doesn't want me to release the start button until its started for sure. Other engines seem to run along, like the car engine or the 454 moho engine...you can turn the start key for basically just a blip, and then the engine seems to have a life of it's own in less than second whereas the gen really appreciates a longer start-hold phase.
Onan Generator starting issues
- Thread starter cougsfan
- Start date
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Lou Schneider
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Cougsfan and Anemic -
What kind of oil are you using? Onan recommends straight 30 weight above freezing in their air cooled engines. A multi-viscosity oil is thinner when cold, so it will take longer to build up pressure on a cold start.
What kind of oil are you using? Onan recommends straight 30 weight above freezing in their air cooled engines. A multi-viscosity oil is thinner when cold, so it will take longer to build up pressure on a cold start.
denmarc
Well-known member
Mavarick said:
WOW! I haven't head the term "overrunning clutch" in a long time. Everyone usually just calls it a Bendix.
Mavarick is on the right track, IMHO.
Mavarick
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Funny how you remember certain names from school 35 yrs ago but I can't remember what I had for breakfast!!! ;D
OP
OP
cougsfan
Member
I changed the oil in the Onan as a first step, and put Chevron 10-40 in it. The old oil didn't look that bad.
I will try disconnecting the oil pressure switch as soon as I can find it. (haven't looked very hard yet), Anemic's situation sounds about identical to mine. You just have to hold the start button significantly longer than you would any other engine you have learned to start over the last (in my case) 60 some years.
One other thing that may mean something. When it tries to fire but doesn't stay running from not holding the start button long enough, the whole generator set physically bounces around a lot in its cushion mounts as it comes to a stop (like it is badly out of balance) With the starter spinning and it not running, and after it does start, it doesn't bounce around at all. Might be normal. It does bounce around a lot when you shut it down too. Don't seem right though.
I will try disconnecting the oil pressure switch as soon as I can find it. (haven't looked very hard yet), Anemic's situation sounds about identical to mine. You just have to hold the start button significantly longer than you would any other engine you have learned to start over the last (in my case) 60 some years.
One other thing that may mean something. When it tries to fire but doesn't stay running from not holding the start button long enough, the whole generator set physically bounces around a lot in its cushion mounts as it comes to a stop (like it is badly out of balance) With the starter spinning and it not running, and after it does start, it doesn't bounce around at all. Might be normal. It does bounce around a lot when you shut it down too. Don't seem right though.
OP
OP
cougsfan
Member
With the help of my new handy dandy service manual (thanks again, John), I tried to track down the oil pressure safety switch. Doesn't have one! It does have a low level oil switch that is in the starting circuit and it is wired to prevent the engine from ever running once the starter switch is released. So if it were low on oil (which it isn't) or if the switch were defective, it would never stay running. The low oil level switch is inside the pan, and I don't really think I want to try get to it. I could disconnect it at pin 12 of the J1 connector (if I knew where that was), and check continuity through the switch.... but I have a hard time believing it would ever run if that switch were bad. I also can't imagine how holding the button in a moment longer would any affect the status of that oil level switch.
Is my logic bad?
Is my logic bad?
Ernie n Tara
Well-known member
Just a thought; these also have a cutout if they are not producing the correct voltage. It has to take a second to get up to 3600 RPM (as I recall) and it may be that holding just a bit longer does the deed.
Since i can't see the light in the switch unless its dark, I use a 5W night light plugged in where i can see it and let off when it gets full bright (there is an obvious delay between first glow and full bright). Rarely have to try more than twice.
Hope this contributes,
Ernie
Since i can't see the light in the switch unless its dark, I use a 5W night light plugged in where i can see it and let off when it gets full bright (there is an obvious delay between first glow and full bright). Rarely have to try more than twice.
Hope this contributes,
Ernie
Lou Schneider
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Are you trying to start the generator with a load on it? That would delay the generator coming up to full voltage, as the armature has to be spinning fast enough to power the load, instead of just developing voltage.
That's one advantage a transfer switch has over direct connection - the 30 second time delay in the switch doesn't connect the load to the generator until after the generator stabilizes.
Ernie n Tara
Well-known member
No load other than the night light and the converter. It does take a noticeable amount of time (perhaps 1-2 seconds) to run up to operating speed per the lamp.
Ernie
Ernie
OP
OP
cougsfan
Member
I generally start mine with no load. As a habit, I turn everything off before ever shutting it down. I have no light anywhere I can find, that I see mentioned in several threads, telling me the thing is generating power.
Actually, I am not sure there is a problem with just holding the switch in longer. I have listened carefully for funny noises from the starter, and don't here anything. It is weird that this little trick works so well. My guess is that it has something to do with slow switching from one energy source to another to power something in the ignition system. (??) I don't know that though. I have thought about hooking up a cheap Harbor Freight spark tester to the plug and watching it if I try to start the generator normally. If my theory is true, the engine will lose strength in the spark when I release the starter switch normally. Think I will wait till a little warmer weather though to go try this.
Actually, I am not sure there is a problem with just holding the switch in longer. I have listened carefully for funny noises from the starter, and don't here anything. It is weird that this little trick works so well. My guess is that it has something to do with slow switching from one energy source to another to power something in the ignition system. (??) I don't know that though. I have thought about hooking up a cheap Harbor Freight spark tester to the plug and watching it if I try to start the generator normally. If my theory is true, the engine will lose strength in the spark when I release the starter switch normally. Think I will wait till a little warmer weather though to go try this.
Mavarick
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Cougs, maybe as Anemic said above, you're not really holding the switch down AFTER it starts - only long enough to get it running. Their is a big difference here and only you can really tell. If you're not hearing any starter noise and think it just needed to be held longer in order to run then it's an easy fix.
Don't know if you would be able to see intensity changes in a spark tester. I suggested the VOM above because all your safeties usually cut + coil power when not happy and this you would be able to see on a meter when you released the switch. Good luck with it.
Don't know if you would be able to see intensity changes in a spark tester. I suggested the VOM above because all your safeties usually cut + coil power when not happy and this you would be able to see on a meter when you released the switch. Good luck with it.
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