Your last generator Maintenance Run

   / Your last generator Maintenance Run
  • Thread Starter
#5,281  
As far testing the battery under starter load, I can't with the generator itself. Before the generator even tries to do anything, that fuse blows. This weekend I'll hopefully..

1. Disconnect battery and load test(battery is close to 6 years old come to think of it)

2. Put in new spark plugs

3. Double check all wiring more thorough

Thank you all for the ideas and what to check. I'll report back with any good/bad results.

This is hands down one of the most helpful forums I've been part of
Sounds like a plan.

If you haven't already, pull it over manually, if it also has a pull-cord. Long shot, but that will verify that the engine is turning over normally w/o the starter being involved.

We've all fought with equipment problems over the years, so it's always good to bounce ideas around here (y) .

Best of luck, and post-up how it goes later this week.

(Last thought..... esp. if the plugs have been in there crazy long, have a really close look at the centre electrode, to make sure it's still there).

Rgds, D.
 
   / Your last generator Maintenance Run #5,282  
Good thoughts all around. Thank you. I know I have a manual somewhere for this thing. But I'm pretty sure the plugs I can still read the number on. No pull cord, but I might be able to spin it manually somehow. Might as well drain and change the oil while I'm in there. Ha
 
   / Your last generator Maintenance Run #5,283  
Maybe I am missing something but since when do starters have fuses inline?,

it SOUNDS like you have a fuse on the start wire to maybe the starter solenoid? if that's the case, sounds like the wire might be shorted. that can be easily tested,

what size is this fuse?

edit... reading above 5 amp? yea no way that's inline. i will defer to @grsthegreat to understand how the 5amp blows due to a bad starter, is this a over amp on the solenoid.

my onan 4k, pulls 60-80amps on start up.
 
   / Your last generator Maintenance Run #5,284  
Maybe I am missing something but since when do starters have fuses inline?,

it SOUNDS like you have a fuse on the start wire to maybe the starter solenoid? if that's the case, sounds like the wire might be shorted. that can be easily tested,

what size is this fuse?

edit... reading above 5 amp? yea no way that's inline. i will defer to @grsthegreat to understand how the 5amp blows due to a bad starter, is this a over amp on the solenoid.

my onan 4k, pulls 60-80amps on start up.
The 5 aps is before the starter relay on some units. Not on the 12 v starter power itself. Ive just seen it lots of times when starters on whole house units start to fail, the draw over this fuse increases and blows the fuse.
 
   / Your last generator Maintenance Run #5,285  
Maybe I am missing something but since when do starters have fuses inline?,

it SOUNDS like you have a fuse on the start wire to maybe the starter solenoid? if that's the case, sounds like the wire might be shorted. that can be easily tested,

what size is this fuse?

edit... reading above 5 amp? yea no way that's inline. i will defer to @grsthegreat to understand how the 5amp blows due to a bad starter, is this a over amp on the solenoid.

my onan 4k, pulls 60-80amps on start up.

The starter solenoid is what I meant and my brain has been mush after this last vacation with what I needed to concentrate on. The fuse, I believe is 5 amps.

Since you have an Onan, what size battery do you have connected to it if you know off hand? Or am I just looking for the best CCA I can find? This battery was here when I moved in, so it very well could be the culprit.

Won't know anything till this weekend at the earliest. Thank you
 
   / Your last generator Maintenance Run #5,286  
Grs, thank you for all the generator help I see you contribute. I'm writing all the ideas down to tackle this ASAP.

I forgot to ask in the previous response, how is it that I can test for a short in that wire that was mentioned? Thank you.
 
   / Your last generator Maintenance Run #5,287  
I usually ohm out suspect battery cables, but you could also place a voltage at the end of the run and verify voltage and amperage during a start. I have found lots of issues over the years with rotted battery cabling and bad ground connections…where the ground wire from battery attaches to frame.

most whole house generators use around 550 CCA batteries in my experience. It’s usually limited by available space inside generator.
 
   / Your last generator Maintenance Run
  • Thread Starter
#5,288  
Good point raised Bill, steering towards the control side.....

I have an Innova really basic manual-ranging DMM that I use most of the time knocking about on automotive stuff. Doesn't look like they still show that model, but if you need/want a basic DMM, have a look at Innova sic. Good value vs. $. If you end up having fun with it, you can save up for a Fluke later :).

Even with a DMM around, this technique can be useful sometimes...... take an incandescent bulb and socket, and use that with a 12v source to temporarily wire into sections of wiring you've opened up for inspection, and aren't sure if they are passing power properly. You use an incandescent bulb (vs. LED) to create sufficient load to test with, you don't have to worry about polarity, and if you are working on a large chassis, you can have a visual indicator that you can see from a distance. This is a course technique to use (blunt hammer approach meaning), but to zero in on a corroded connector, or loose pins etc, it's often all that you need. An old sealed-beam headlight/foglamp is an ideal load, but anything smaller will work too.

Caveats ^ ........ older generators being pretty simple, you can't get into too much trouble, but keep the following in mind:

Modern auto electronics sometimes don't react well ($$$) to power being introduced where it shouldn't be, so the headlamp technique is most safe being used on totally disconnected wiring. In other words, you are playing with an "empty" harness.

Fusing the test bulb is a good idea, but if you are just playing with a battery+bulb+wiring, don't lose track (turn off cell phone etc) of where you are at..... too easy to start an electrical fire w. "I'll just be gone for a minute....."

If you don't have a Manual for that gen, post the model # if you can still see it, somebody may come up with a schematic....

Rgds, D.
 
   / Your last generator Maintenance Run #5,289  
Very difficult to read I know... Can't seem to locate my manual at this time. Any help greatly appreciated...
20161028_103909.jpg
 
   / Your last generator Maintenance Run
  • Thread Starter
#5,290  
 
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