Generators and Motors
[Home] - [HELP] - [Forums] - [Library] - [Photo Gallery] - [Groups] - [Classified Ads] - [Subscribe] - [Links] - [Books] - [Sponsors] -

Go Back   SmokStak > SmokStak® Vintage Electrical Equipment > Generators & Electric Motors General Discussion > Onan Generators
Forgot Password? Join Us!

Notices

Onan Generators Restoring, operating and maintaining vintage Onan generators.

Onan Generators

What Have You Done to Your Onan Generator Today?


this thread has 4680 replies and has been viewed 308327 times

Reply
 
Thread Tools Display Modes
  #1761  
Old 07-18-2015, 09:57:48 PM
YellowLister YellowLister is offline
Registered-III
 
Join Date: Feb 2010
Location: Key Largo, Florida
Posts: 4,565
Thanks: 2,554
Thanked 2,464 Times in 1,543 Posts
Default Re: What have you done to your Onan generator today?

pic of the condensation around the carb.. my old vw with twin webers use to do this when it was humid or cold
Attached Thumbnails
Click image for larger version

Name:	2015-07-18_17-43-09_631.jpg
Views:	58
Size:	63.8 KB
ID:	230009   Click image for larger version

Name:	ResizedImage_1437270461541.jpg
Views:	56
Size:	69.4 KB
ID:	230011  
Reply With Quote
Sponsored Links
  #1762  
Old 07-19-2015, 01:03:04 PM
len k len k is offline
Registered-III
 
Join Date: Jun 2012
Location: Manchester, New Hampshire
Posts: 17,045
Thanks: 491
Thanked 6,232 Times in 4,528 Posts
Default Re: What have you done to your Onan generator today?

Started up my 7NHM to exercise it. Was real humid , carb was sweating too. Would expect this of any carb not warmed by engine (long intake).

Ethanol gas finally caught up with me. Today I also started my car across the street to exercise it, car has been parked for few years. I only start car every 3-6 months. Warmed it up. Drove it up and down the street, then floored it to exercise all the transition gears, it stalled out. Turns out gas pump in tank died again, just replaced it ~ 1-2 years ago. Pump was running then nothing, even applying 12V to pump wires. Draws current but doesn't turn. Hammering tank and reversing polarity didn't clear it. Guess I have to drop tank again.

Humm I wonder if quickly applying 24 V will jar it free? I suspect fuel/air ratio in tank is too high to ignite even if there's a spark.

Last edited by len k; 07-19-2015 at 02:00:15 PM.
Reply With Quote
  #1763  
Old 07-19-2015, 02:04:30 PM
nothingbutdarts nothingbutdarts is offline
Sponsor
 
Join Date: Apr 2014
Location: Bailey, Colorado, USA
Posts: 2,804
Thanks: 6,631
Thanked 1,416 Times in 907 Posts
Default Re: What have you done to your Onan generator today?

Let us know how the 24volts works!
Reply With Quote
  #1764  
Old 07-19-2015, 02:09:32 PM
len k len k is offline
Registered-III
 
Join Date: Jun 2012
Location: Manchester, New Hampshire
Posts: 17,045
Thanks: 491
Thanked 6,232 Times in 4,528 Posts
Default Re: What have you done to your Onan generator today?

Myth Busters tv show even fired tracer rounds into a gas tank and it didn't explode, gas only ignited AFTER it leaked out of tank holes. Suppose I should first test that no spark ignition theory with a coffee can, and a small piece of glass/plastic for a gravity lid.

Last edited by len k; 07-19-2015 at 02:20:21 PM.
Reply With Quote
  #1765  
Old 07-19-2015, 02:40:12 PM
BigBlockChev's Avatar
BigBlockChev BigBlockChev is offline
Subscriber
 
Join Date: Jan 2007
Location: Coquitlam, BC, Canada
Posts: 2,136
Thanks: 383
Thanked 1,669 Times in 969 Posts
Default Re: What have you done to your Onan generator today?

I would suggest trying 12V with a bit of percussive maintenance applied while it is powered up, it may break free. Or just pull the tank and take it out, the easy way is the hard way. Cheers Dan
__________________
It's always something simple.
One test is worth a thousand guesses.
If some is good and more is better then too much is just enough
Reply With Quote
  #1766  
Old 07-19-2015, 02:46:53 PM
len k len k is offline
Registered-III
 
Join Date: Jun 2012
Location: Manchester, New Hampshire
Posts: 17,045
Thanks: 491
Thanked 6,232 Times in 4,528 Posts
Default Re: What have you done to your Onan generator today?

I did whack plastic tank with a good sized rubber hammer, pump powered up and unpowered .....no change. I can try whacking it reverse powered. When I disassembled bad pump 2 years ago it had rust spanning rotor/stator gap.
Reply With Quote
  #1767  
Old 07-19-2015, 03:07:51 PM
YellowLister YellowLister is offline
Registered-III
 
Join Date: Feb 2010
Location: Key Largo, Florida
Posts: 4,565
Thanks: 2,554
Thanked 2,464 Times in 1,543 Posts
Default Re: What have you done to your Onan generator today?

you might be able to hook up a secondary fuel pump to pump the old fuel out.. what kind of car is it?

I wouldn't worry about it blowing up.. I mean if it does you wont have to worry about it, most likely.. when I drove tow trucks we did the rubber mallet smack on the gas tank and sometimes it worked..
Reply With Quote
  #1768  
Old 07-19-2015, 03:31:12 PM
len k len k is offline
Registered-III
 
Join Date: Jun 2012
Location: Manchester, New Hampshire
Posts: 17,045
Thanks: 491
Thanked 6,232 Times in 4,528 Posts
Default Re: What have you done to your Onan generator today?

92 Chev caprice.
I'ld rather just drop the tank and replace it. Pretty simple, not much to it, just a pain. Guess I have to start it more often to keep it from rusting. Gotta drain the old gas and try stabilizer and new gas . after I put in new pump.

About a month ago on the 93 caprice I replaced same pump. Took pump off my Onan NHM and pumped 15 gallons between cars in 50 minutes. got it all out too. There's a in tank ~ 8" box shield around pump and float sending unit so you can't bend them with a siphon hose.

Last edited by len k; 07-19-2015 at 04:38:05 PM.
Reply With Quote
  #1769  
Old 07-19-2015, 04:38:17 PM
len k len k is offline
Registered-III
 
Join Date: Jun 2012
Location: Manchester, New Hampshire
Posts: 17,045
Thanks: 491
Thanked 6,232 Times in 4,528 Posts
Default Re: What have you done to your Onan generator today?

Hammer usually works on starter motors...... for a week.

THE FLAME TEST... ahh now the fun starts.
Took a coffee can and made a hi-voltage feed thru. Punched ~ 3/8 dia hole in can, inserted an insulated wire, and potted up the hole with car Bondo. Added a 1/4 inch of gasoline, put a small plate of glass on top , and let it sit 5-10 minutes in the shade to let the gas evaporate. Wired in a hi-voltage sparker from an old grill, hit the sparker. Could clearly see the spark ~ 1/2 long from wire to inside surface of can, no flame.

Wire spark gap was at mid-height of can, I then lowered it to make spark gap close to surface of gas and sparked again, no flame. Took cover off and sparked again still no flame (gas vapor is heavier than air). Fanned some air into can with glass plate, sparked it, finally got flame.

Just to be thorough I moved spark gap to top of can, sparked it, no flame. Removed glass cover , sparked it , got flame.

So I think I will be safe playing with higher voltage to pump in tank, even if it does happen to spark inside tank. But for extra safty I'll add ~10 ft of romex wire for extra distance.

Hummm if 24 V doesn't work I'll try a small cap charged to a high voltage ~ 50VDC. Small cap can limit wire melting energy deposited in motor. Momentary high current might demagnetize permanent magnets in motor but it's junk anyways.

Last edited by len k; 07-19-2015 at 08:34:57 PM. Reason: added test with spark gap at top
Reply With Quote
The Following User Says Thank You to len k For This Post:
  #1770  
Old 07-19-2015, 05:34:40 PM
Jim McIntyre's Avatar
Jim McIntyre Jim McIntyre is offline
Subscriber
 
Join Date: Nov 2004
Location: Mooresville, Indiana, USA
Posts: 4,260
Thanks: 755
Thanked 2,401 Times in 1,393 Posts
Default Re: What have you done to your Onan generator today?

Quote:
Originally Posted by len k View Post
...So I think I will be safe playing with higher voltage to pump in tank, even if it does happen to spark inside tank..
Yep. Gasoline has a high enough vapor pressure that the gas mixture over it won't burn.

Diesel is the opposite - low enough VP the mixture won't combust.

Any guess as to what happens when you mix them???
Reply With Quote
Reply

Bookmarks


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

F o r u m Jump

Similar Threads Chosen at Random
Thread Thread Starter F o r u m Replies Last Post
Saw this generator hook up cord in ad today. len k Onan Generators 40 07-09-2016 10:10:20 PM
onan 10 cw on cl today, cheap Mikey NY Onan Generators 1 08-21-2014 09:09:51 AM
saw an Onan today the likes of which I've never seen before armandh Onan Generators 12 04-27-2014 04:44:41 PM
Got old Onan genset today,no id tag. p fears Onan Generators 4 05-03-2009 09:56:02 AM
old aircraft generator followed me home today clifton clowers Generators & Electric Motors General Discussion 4 11-21-2003 11:39:36 AM


Use "Ctrl" mouse wheel to change screen size.
All times are GMT -4. The time now is 03:27:47 AM.

Smokstak and Enginads site search!


All use is subject to our TERMS OF SERVICE
SMOKSTAK® is a Registered Trade Mark - A Community of Antique Engine Enthusiasts
Copyright © 2000 - 2016 by Harry Matthews P.O. Box 5612 - Sarasota, FL 34277