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

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

Notices

Onan Generators Restoring, operating and maintaining vintage Onan generators.

Onan Generators

Onan Electronic Ignition and TriFuel... How To


this thread has 55 replies and has been viewed 20086 times

Reply
 
Thread Tools Display Modes
  #41  
Old 11-08-2012, 09:57:00 PM
Onan Dan's Avatar
Onan Dan Onan Dan is offline
Subscriber
 
Join Date: Oct 2012
Location: Waynesburg, Pennsylvania
Posts: 3,508
Thanks: 7,619
Thanked 2,531 Times in 1,302 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

well folks i took the easy route on my bfa 4.0 onan .it has the walbro carb. so i set me an adaptor down on the carb. so its still gasoline and natural gas. i have good hot casing head gas and the load i put 3625 watts on it and it did great. did not change any settings on any plugs or points. the bfa started up this morning on natural gas at 20 degrees like summer time. only thing on my natural gas inlet before the zero gravity regulator i have a 3/8" ball valve i have to crack it open just enought to start the onan and it warms up a little then i can open the ball valve wide open. so it seems to work good. i hope it don,t melt the pistons,thats yet to come?
Reply With Quote
Sponsored Links
  #42  
Old 11-08-2012, 10:18:20 PM
MBB MBB is offline
Registered-III
 
Join Date: Apr 2009
Location: Elk Grove Village IL USA
Posts: 2,864
Thanks: 1,195
Thanked 2,011 Times in 1,149 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

Run it a little leaner on Natural gas or propane. Rich burns valves and pistons. Just the opposite of gasoline.
Reply With Quote
The Following 2 Users Say Thank You to MBB For This Post:
  #43  
Old 11-09-2012, 01:09:13 AM
lokay5's Avatar
lokay5 lokay5 is offline
Subscriber
 
Join Date: May 2007
Location: Merlin, Oregon
Posts: 1,264
Thanks: 3,268
Thanked 739 Times in 464 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

"That area is VERY thin."

It is indeed. That area is thin because it's simply a flat surface that mates with the factory gaseous adapter. It wasn't designed to be threaded for pipe nor to hold any weight at all.

" For best results, your timing should be set from 19, to 21 for gasoline/natural gas, and 25 for natual gas only, because natural gas/propane burns slower."

So what do you suggest for timing when using strictly propane ?

"Also the heads should be cut or replaced with higher compression heads. Any desent shop and cut the heads down."

The problem with machining the heads is that you can encounter valve to head crash. To remedy that, you fly cut the combustion chamber above the valves for clearance, but by doing that you increase the chamber volume which lowers the compression.
Relieving also improves breathing and power on a flathead, but, then again, it also lowers the compression. But I digress...
(I've built a few flatties in my 66 years on this rock. Can you tell? )

"Even with all of this, you still aint going to get 100% of the power."

My propane-fueled 4kw BF holds a continuous 4kw 240V space heater load @ 60~ & 1800 RPM with a factory Marvel-Schebler VD 60, tri-fuel carburetor and still has throttle left.

FLATHEADS FOREVER !
Reply With Quote
The Following 2 Users Say Thank You to lokay5 For This Post:
  #44  
Old 11-09-2012, 01:38:32 AM
Jim McIntyre's Avatar
Jim McIntyre Jim McIntyre is offline
Subscriber
 
Join Date: Nov 2004
Location: Mooresville, Indiana, USA
Posts: 3,713
Thanks: 594
Thanked 1,909 Times in 1,132 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

I decided not to drill the upper boss. Yes it is thin, but the main problem was that my CCK points tower would have prevented getting a fuel line in to feed a nipple installed in that upper boss. Picture 1 shows a pencil barely fits in the space - just not enough room. And I want the option to keep the points tower as-is. The points seem to work fine...

So, I pondered other options. And since I don't need 'tri-fuel' operation, I decided on a more radical mod. First I disassembled the carb, removed the choke plate and shaft. And then I drilled out the gasoline input boss - straight through to 7/16" as shown in picture 2. Then I tapped one side for a gas inlet nipple at 1/4" NPT as shown in picture 3. The other side I tapped for a 1/2"-13 bolt that will act as a crude mixture adjustment valve.

Picture 4 shows the carb upper body with both the mixture bolt and fuel inlet nipple installed.
Attached Thumbnails
Click image for larger version

Name:	pic1 no room for fuel line.jpg
Views:	194
Size:	100.4 KB
ID:	149034   Click image for larger version

Name:	pic2 drill meets carb.jpg
Views:	201
Size:	94.3 KB
ID:	149035   Click image for larger version

Name:	pic3 tap meets carb.jpg
Views:	194
Size:	85.7 KB
ID:	149036   Click image for larger version

Name:	pic4 nipple and  mixture screw in carb.jpg
Views:	210
Size:	133.3 KB
ID:	149037  


Last edited by Jim McIntyre; 11-09-2012 at 01:47:30 AM. Reason: kan't spel
Reply With Quote
The Following 2 Users Say Thank You to Jim McIntyre For This Post:
  #45  
Old 11-09-2012, 01:43:12 AM
Jim McIntyre's Avatar
Jim McIntyre Jim McIntyre is offline
Subscriber
 
Join Date: Nov 2004
Location: Mooresville, Indiana, USA
Posts: 3,713
Thanks: 594
Thanked 1,909 Times in 1,132 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

So the mods just described allow fuel gas to flow into the 'bowl' area of the carb. To get the gas to flow into the venturi, I just cut 2 slots through the walls of the venturi with a little keyway cutter as shown in picture 5...

Will it work? But it's fun to tinker...
Attached Thumbnails
Click image for larger version

Name:	pic5 add slots.jpg
Views:	179
Size:	99.9 KB
ID:	149038  
Reply With Quote
The Following User Says Thank You to Jim McIntyre For This Post:
  #46  
Old 11-09-2012, 08:24:13 AM
MBB MBB is offline
Registered-III
 
Join Date: Apr 2009
Location: Elk Grove Village IL USA
Posts: 2,864
Thanks: 1,195
Thanked 2,011 Times in 1,149 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

Jim There is a short point tower that would have allowed you to still keep your points. That being said im interested to see if your idea works. Onan had a factory modefied carb that had a similar idea only I believe they drilled it out like you did and fitted the gas vapor line to the area you drilled and had a metering valve pointing down. I would have to look there is a repair shop close to me that does work on Onans and he was showing me the carb. I bought a gas vapor carb from him I planned to put on my 305cck.
Reply With Quote
The Following User Says Thank You to MBB For This Post:
  #47  
Old 11-09-2012, 08:50:08 AM
Slick 50 Slick 50 is offline
Registered-II
 
Join Date: Aug 2010
Location: Texas
Posts: 217
Thanks: 55
Thanked 46 Times in 40 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

Jim, love your thinking.
Rick
Reply With Quote
The Following User Says Thank You to Slick 50 For This Post:
  #48  
Old 11-17-2012, 12:40:01 AM
Jim McIntyre's Avatar
Jim McIntyre Jim McIntyre is offline
Subscriber
 
Join Date: Nov 2004
Location: Mooresville, Indiana, USA
Posts: 3,713
Thanks: 594
Thanked 1,909 Times in 1,132 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

So far, so good. The 4.0CCK genset runs great, starts with no priming, and carries 4 kW of load on natural gas. (Now that's at wide open throttle, it completely maxed out). I'm not done tinkering at the carb and governor adjustments and the vacuum speed booster, but even at that, I'm getting 5 Hz droop, which is tolerable, but not quite in spec.

Setting the timing at 24 degrees helped. Initially, it was at about 18 degrees, and I got only 3.5 kW at full throttle.

The engine does have an audible exhaust valve leak, but I'm not inclined to do anything about it, since it seems to run just fine as-is...
Reply With Quote
  #49  
Old 11-17-2012, 02:51:44 AM
gtj811 gtj811 is offline
Subscriber
 
Join Date: Aug 2009
Location: Hobart, Wisconsin
Posts: 211
Thanks: 371
Thanked 39 Times in 30 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

Nice job. Just curious, how do you adjust the timing on the onan engine? I have a 5 BGA converted to propane that I would like to adjust. Thanks
Reply With Quote
  #50  
Old 11-17-2012, 06:10:27 AM
lokay5's Avatar
lokay5 lokay5 is offline
Subscriber
 
Join Date: May 2007
Location: Merlin, Oregon
Posts: 1,264
Thanks: 3,268
Thanked 739 Times in 464 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

Ignition timing is set with point gap:
Wider gap advances the timing.
Narrower gap retards it.
Reply With Quote
The Following User Says Thank You to lokay5 For This Post:
  #51  
Old 11-17-2012, 12:48:07 PM
AndersonMillTexas AndersonMillTexas is offline
Registered-III
 
Join Date: Oct 2012
Location: Boston, Massachusetts
Posts: 484
Thanks: 291
Thanked 47 Times in 39 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

Greetings everyone,

Thank you for your assistance. Cleaning and adjusting the plugs got the engine to start.
However, i must splash gasoline in the carb to get it to run and it will only stay running until the splash is used up.

Back to the manuals!!!!!
Reply With Quote
  #52  
Old 03-21-2014, 10:29:00 PM
Weasel Weasel is offline
Registered
 
Join Date: Mar 2014
Location: Chillicothe, Ohio
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

I reading complete details on main gaseous jet and understand it all, but the details on the idle tube going to front of carb.My question is about where the idle tube connects and if drilling is required;Which direction, how deep.I see a landing beside soline run jet opposite the idle screw.Anyone out there w/this factory carb(tri-fuel) I'm lookin
Reply With Quote
  #53  
Old 10-30-2015, 02:29:18 PM
johngubler johngubler is offline
Registered
 
Join Date: Oct 2015
Location: Tehachapi, California, USA
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: Electronic Ignition and TriFuel.. How To

I'm new here so go easy on me I have ordered all the parts to convert an onan cckb engine to electronic ignition my question is do I need to upgrade the coil as well or will the original coil that was used for the points ignition work for the electronic ignition thanks for the help and for the fantastic write up on this subject. for whatever it's worth the Onan engine is from a Fairmont Mt-19 rail speeder
Reply With Quote
  #54  
Old 10-30-2015, 05:46:08 PM
MBB MBB is offline
Registered-III
 
Join Date: Apr 2009
Location: Elk Grove Village IL USA
Posts: 2,864
Thanks: 1,195
Thanked 2,011 Times in 1,149 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

If your following Bobby instructions no need to change the coil.
Reply With Quote
The Following User Says Thank You to MBB For This Post:
  #55  
Old 01-20-2016, 03:35:25 PM
johngubler johngubler is offline
Registered
 
Join Date: Oct 2015
Location: Tehachapi, California, USA
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: Electronic Ignition and TriFuel.. How To

although the original 6 volt coil worked I ended up upgrading to a later 12 volt coil to simplify things I'm guessing it puts out a stronger spark as well in any case the conversion went well
Reply With Quote
  #56  
Old 02-25-2016, 10:24:40 AM
don theroux don theroux is offline
Registered
 
Join Date: Feb 2016
Location: Cranston, Rhode Island, USA
Posts: 1
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: Onan Electronic Ignition and TriFuel... How To

Will this procedure work on a 1988 6.5 MCCK
Reply With Quote
Reply


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
OEM Electronic Ignition for Onan AJ redrockx Onan Generators 24 05-06-2017 04:38:13 PM
My Electronic Ignition for Onan 4 CCK K D Redd Onan Generators 39 06-30-2012 11:42:40 PM
Onan Electronic Ignition Cruiser Onan Generators 3 10-18-2010 10:31:01 AM
Onan electronic Ignition conversion ? NF BF GHanners Onan Generators 2 09-19-2009 07:40:49 AM
Electronic ignition for 4kw BH-series Onan gkitf16 Onan Generators 5 03-15-2009 02:14:35 PM


Use "Ctrl" mouse wheel to change screen size.
All times are GMT -4. The time now is 04:53:34 PM.

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