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Onan 4000 won't start...again

Artum_Snowbird
Explorer
Explorer
A month or so ago I posted about my generator not starting. I thought it was the starting solenoid. I did buy a new one, installed it, and it's exactly the same problem still.

The generator clicks, but will not turn over. This is a two year old unit with only 80 hours on it.

So, I took a measurement of the voltage into the starting solenoid. On shore power 14 volts. When I engage the start button, full voltage goes to the new start solenoid. Same clicking sound. Output of the start solenoid is still 2.7 volts.

Somehow, voltage is being sucked down. Flywheel turns easily. I used the 9/16 wrench on the fan, no problem there. No whirring sounds from the starter at all.

I put jumper cables onto the unit ground, and the positive terminal of the start solenoid. No change.

It does not turn over at all.

Any suggestions before I have to pull the unit out and go directly to the starter?
Mike
2012 Winnebago Impulse Silver 26QP
2005 16.6 Double Eagle
2018 Jeep Wrangler JK
previously Snowbird Campers,
Triple E Motorhome and Fifth Wheel
28 REPLIES 28

Kpackpackkelley
Explorer
Explorer
Youโ€™ve e got to get the starter off and check it. Put it in a vice and apply 12 volts.

Ranger_Smith
Explorer
Explorer
Did you tap the starter . . . Possibly a dead spot
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Amateur Radio Operator WW1SS . . . Flex 6500 PGXL and TGXL
Steve and Joy
2014 Itasca Suncruiser 38Q . . . 2016 Lincoln MKX
The Doodles, Abbie & Abel
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Artum_Snowbird
Explorer
Explorer
Used my professional DC ammeter, got 12 volts through the solenoid this time, and about a half amp. Should be 20 amps or perhaps lots more than that I would think.
Mike
2012 Winnebago Impulse Silver 26QP
2005 16.6 Double Eagle
2018 Jeep Wrangler JK
previously Snowbird Campers,
Triple E Motorhome and Fifth Wheel

Ranger_Smith
Explorer
Explorer
It is telling you I believe you have an open in the starter motor and it needs to be replaced. Pull it out and have it tested at an auto electric shop before you purchase a new one.
Where we are now

Amateur Radio Operator WW1SS . . . Flex 6500 PGXL and TGXL
Steve and Joy
2014 Itasca Suncruiser 38Q . . . 2016 Lincoln MKX
The Doodles, Abbie & Abel
Baby and Kissie the Chihuahuas and Lucy the Biewere Yorkie

LittleBill
Explorer
Explorer
either the wiring is bad or the start is bad, connect power directly at the starter, and or throw an amp meter on the starter cable, and or do a voltage drop test while cranking to rule out the wire

Artum_Snowbird
Explorer
Explorer
Ranger Smith wrote:
You will not hear a click The starter motor should turn. You might get a lot of sparks if the motor has a short. You will only hear the click when you engage the solenoid.


Nothing happened, not a thing. I have negative connected to the bolt on the bottom and positive connected to the start solenoid output.

What is this telling me?
Mike
2012 Winnebago Impulse Silver 26QP
2005 16.6 Double Eagle
2018 Jeep Wrangler JK
previously Snowbird Campers,
Triple E Motorhome and Fifth Wheel

MEXICOWANDERER
Explorer
Explorer
The starter motor may spin with a bypass of the solenoid and still the starter motor might be bad.

Under load of cranking the flywheel the sickly spin will stall -- so don't be fooled by an ambiguous free-air spin test. Free air spin should be no more than 20 amps continuous.

Lots of garbage amateur rebuilds out there. And trouble have been reported with new Chinese starters.

Dependable rebuilts without insane Onan prices can be had at

ROMAINE ELECTRIC. Google for the store nearest you. You will need the stamped number right off the main case. Count the starter gear teeth to be sure. Sandpaper rubbed across the numbers stamped in the case will bring out the numbers.

Ranger_Smith
Explorer
Explorer
You will not hear a click The starter motor should turn. You might get a lot of sparks if the motor has a short. You will only hear the click when you engage the solenoid.
Where we are now

Amateur Radio Operator WW1SS . . . Flex 6500 PGXL and TGXL
Steve and Joy
2014 Itasca Suncruiser 38Q . . . 2016 Lincoln MKX
The Doodles, Abbie & Abel
Baby and Kissie the Chihuahuas and Lucy the Biewere Yorkie

Artum_Snowbird
Explorer
Explorer
Ranger Smith wrote:
No the starter motor should turn.


Assuming I do this test, if there is something wrong, will I still hear the clicking or not?
Mike
2012 Winnebago Impulse Silver 26QP
2005 16.6 Double Eagle
2018 Jeep Wrangler JK
previously Snowbird Campers,
Triple E Motorhome and Fifth Wheel

Artum_Snowbird
Explorer
Explorer
Definitely got you covered with your suggestion DrewE. Thank you for that. Will drive up on quite a few blocks and set that up for clearance.
Mike
2012 Winnebago Impulse Silver 26QP
2005 16.6 Double Eagle
2018 Jeep Wrangler JK
previously Snowbird Campers,
Triple E Motorhome and Fifth Wheel

Ranger_Smith
Explorer
Explorer
No the starter motor should turn.
Where we are now

Amateur Radio Operator WW1SS . . . Flex 6500 PGXL and TGXL
Steve and Joy
2014 Itasca Suncruiser 38Q . . . 2016 Lincoln MKX
The Doodles, Abbie & Abel
Baby and Kissie the Chihuahuas and Lucy the Biewere Yorkie

Artum_Snowbird
Explorer
Explorer
So my question would be: If I connect my jumper cables to the battery terminals, and then connect negative to generator ground and positive to the start solenoid output, should I hear the same clicking sound without pressing start on the generator. Will that direct connection actually cause the starter to turn over or do I need to press start?
Mike
2012 Winnebago Impulse Silver 26QP
2005 16.6 Double Eagle
2018 Jeep Wrangler JK
previously Snowbird Campers,
Triple E Motorhome and Fifth Wheel

DrewE
Explorer II
Explorer II
Unfortunately, I agree with Ranger Smith; pull the generator. It took me a good portion of a day to do that on my class C (for much the same reason--bad starter).

One hint: assuming you will have to drop the generator down, vs. extract it horizontally, measure the clearance underneath to see if you have sufficient for the generator plus a wheeled floor jack before you begin, and if needed jack/block up the RV. These units weigh something like 150-175 pounds, if I remember, and it's a bummer to have to extract the starter with the generator sitting under the RV and the top cover on the generator lifted up into the generator mount on the RV because of insufficient planning beforehand. Don't ask me how I know this. :B

Ranger_Smith
Explorer
Explorer
Sounds like the starter motor itself is bad
Where we are now

Amateur Radio Operator WW1SS . . . Flex 6500 PGXL and TGXL
Steve and Joy
2014 Itasca Suncruiser 38Q . . . 2016 Lincoln MKX
The Doodles, Abbie & Abel
Baby and Kissie the Chihuahuas and Lucy the Biewere Yorkie