I think I blew up my generator

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Conquest aka Robert said:
Does it crank? Did oil get on/behind the start switch? Is there oil on any of the electrical contacts. Is there a fusable link in any of the wiring? Any other fuses or circuit breakers you could have missed seeing? There were some issues on page 30 about oil pressure. Looks like you need to start at the top of the list and go thru them ALL.  :eek:
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It does not crank, there is no oil on the start switch. There is some oil on the coil. I have not found a fusable link. I have found all the fuses and circuit breakers. The two wires from the battery are about 3 feet long and go directly to the gen. No fuses or cb in between. There are two fuses on the gen and I have checked them both twice. Lack of oil pressure won't stop it from starting. I will start with the troubleshooting guide in the morning. Thanks for your help.
 
bobsharon said:
Good manual.
Check on page 29. It has a very well laid out troubleshooting chart. It also has a picture showing location of fuses and starter solenoid. I can't give better directions than those provided by this section.
Bottom line, to crank, the solenoid must be energized when start is depressed and can not if there is no voltage to it. The solenoid when energized provides voltage to the starter motor.
You will have to check voltages and continuity with a multimeter. Page 28 provides an electrical schematic and a general description of what happens during the crank/start cycle.
Good Luck

Bob
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I will start trouble shooting it in the morning. Thanks for the help.
 
Tom, glad you were able to find the manual online, saves a lot of guesswork. The troubleshooting will be much easier being an older (pre-control board) model. Your oil psi switch only stops the run circuit, not the crank circuit. You already verified the fuses so now you can pretty much narrow it down with a multimeter in the control box. Hope it?s something simple.
 
I was just reading the trouble shooting part of the manual and it looks like the only thing it can be is the start solenoid. If so that will be easy to find and cheap and easy to replace. But how bizarre would it be to have the start solenoid go out when the oil gushed everywhere. It must be a coincidence because I don't think the oil can hurt a start solenoid. It is one of those sealed units you find on every older Ford.
 
Tom,

It just might be a coincidence. With no noticeable sign of a solenoid operating, it could be just a bad one. It just might have been on the verge of failure when the oil problem happened.
 
seilerbird said:
Well the whole problem with that is that there is no control board. Here is my model number and serial number:

4.0 BFA- 1R/16004C
E853907704

The service manual for my generator is here:

http://asavage.dyndns.org/Onan/display1.php?Path=900-0337&db=Onan&table=900_0337&Page=front

I have found nothing in it that seems to help me with my problem so far.
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Tom,

Be sure you are using the proper section of the manual for troubleshooting ... you have the BFA.  someone mentioned the troubleshooting on page 29, but for BFA it starts on page 35 ... may or may not make a difference.  Also on page 35 they mention spec "a-c' ... that can also make a difference on wiring, etc.  You didn't mention a "Spec" but it should be on the same tag as model number.  For example I worked on a 4KW in my old Mirada (99) that did not have a low oil pressure/quantity (don't remember which) switch on the Spec H I think it was, and it did indicate that correctly on wiring diagrams, etc.  but apparently most other "spec/models" do have the switch.

Good luck,

Howard
 
Thank you for noticing that Howard. I was using the wrong section, now it looks better.
 
Tom,

Have you tried shorting across the two main contacts of the solenoid with a screwdriver to confirm that the starter will still crank the motor over? This would help determine if the solenoid is part of the problem. Does the wire from the start switch deliver voltage to the solenoid coil?
 
Great catch by Howard. I didn?t notice the different sections. The troubleshooting instructions on page 37 are different in detail from those on 29. Actual points to check for voltage vary between the instruction sets.
Chet?s suggestion to jumper across the large contact lugs on the starter solenoid is a good one although if picture of solenoid is correct it may not work with a screwdriver. A pair of pliers might bridge the two large contacts. Be careful; expect an arc when you jumper them.
 
I just went outside and shorted out the two terminals on the start relay and as expected it did turn over, so now I know I did not seize the engine. Now I must dig out my brand new multimeter and start using the Onan manual to trouble shoot the ignition circuit.
 
I followed the troubleshooting guide in the Onan service manual and I found a blown fuse. I don't think that fuse was blown yesterday but I didn't put a meter on it, I just eyeballed it. I might have blown it when I jumpered the start solenoid. It is an AGC 5 amp and all I have are 3 amp and 20 amp fuses so I am stuck until next weekend when I will get to an auto parts store.
 
No AGC fuses in your rig anywhere else you can "borrow'" to  test it out?? A 6,8a, would would do just fine for a temporary test, even for a union electrician....  (heh, heh) 8)

(You can get these glass types types at Home Hardware etc. if that would help!!!
 
You can safely attempt to use the 3 amp fuse.
Fuses are installed to protect wiring and input paths from over-current and may be overrated for amount of expected current they will draw. Pull down current for the solenoid shouldn't exceed 1 Amp.
Worse case would be the 3 amp fuse would blow if attempted.
 
bobsharon said:
You can safely attempt to use the 3 amp fuse.
Fuses are installed to protect wiring and input paths from over-current and may be overrated for amount of expected current they will draw. Pull down current for the solenoid shouldn't exceed 1 Amp.
Worse case would be the 3 amp fuse would blow if attempted.
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I know I could use the 3 amp safely, but they are quick blow and the one that was in there is a normal fuse. The quick blow would go out in a heartbeat.
 
Alfa38User said:
No AGC fuses in your rig anywhere else you can "borrow'" to  test it out?? A 6,8a, would would do just fine for a temporary test, even for a union electrician....  (heh, heh) 8)

(You can get these glass types types at Home Hardware etc. if that would help!!!
Click to expand...
All the glass fuses here are 10 amp or better. The rest are the plastic ones.

There isn't a Home Hardware, Walmart or auto parts store for 75 miles in all directions.
 
Well now that I know that the gen is not seized I am not in a rush. I have moved into an RV park and I have shore power. In fact it is against the rules to run a generator here. I will be heading out on Thursday and I will buy the right fuses in Kingman.
 
Tom, are you having fun yet??

  That will be an expensive fuse going to Kingsman and back. What if that doesn't fix it?? :(

I would not hesitate to temporarily use a 10 amp fuse to see if the engine will start. If there is a major short somewhere that fuse will blow.  I think  ;) ;)

  carson FL

 
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