| My Onan Runs Like sheet Episode IV: The Onan gets "Owned" [message #83815] |
Sun, 09 May 2010 18:19  |
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Well for those of you following this saga, over the last 2 months my Onan has been a major pain in my ass, refusing to function correctly.
I tried everything and I mean everything to get it to run correctly. I wanna thank the members here who offered me advice and assistance with parts and trouble shooting to get it running correctly.
Turns out all along it was indeed the original points ignition not keeping a proper timing. this is waht cause the erratic running conditions.
Following a members tip I ordered a pertronix and installed it yesterday. It was a bear as I used a VW model but in hind sight I needed a unit with a yellow dot as the VW unit does not show where it is sensitive and I destroyed 3 of my 4 magnets in the process of dialing the unit in.
Finally at about 23:00 hours last night I achieved Victory over the green turd, with a fixed timing of about 28-30 degrees. my unit has a 25 degree mark so it is an early Onan. the slight advance made a big difference and timing is spot on. the unit now puts out a steady 125 volts and only wonders in tenths of volts instead of + or - 10 volts. the Onan now runs like a Swiss watch!
What a difference a little timing makes, only RPM changes are under load changes, and she settles in right back at 125 volts even under load in about a second or 2!
if you have an Onan and its running is suspect, or if it runs good enough but you want to eliminate that occasional stumble, go with a pertronix install and timing between 25-30 degrees! it fixes whats wrong with the green troll IMHO! Also now the Onan burns clean, no more stinky onan exhaust!!
73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
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| Re: [GMCnet] My Onan Runs Like sheet Episode IV: The Onan gets "Owned" [message #83871 is a reply to message #83815] |
Mon, 10 May 2010 01:09  |
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ljdavick
Messages: 3548
Registered: March 2007
Location: Fremont, CA
Karma: -3
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Senior Member |
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Excellent news! Congratulations.
Larry Davick
The Mystery Machine
On May 9, 2010, at 4:19 PM, Shan Rose wrote:
>
>
> Well for those of you following this saga, over the last 2 months my Onan has been a major pain in my ass, refusing to function correctly.
>
> I tried everything and I mean everything to get it to run correctly. I wanna thank the members here who offered me advice and assistance with parts and trouble shooting to get it running correctly.
>
> Turns out all along it was indeed the original points ignition not keeping a proper timing. this is waht cause the erratic running conditions.
>
> Following a members tip I ordered a pertronix and installed it yesterday. It was a bear as I used a VW model but in hind sight I needed a unit with a yellow dot as the VW unit does not show where it is sensitive and I destroyed 3 of my 4 magnets in the process of dialing the unit in.
>
> Finally at about 23:00 hours last night I achieved Victory over the green turd, with a fixed timing of about 28-30 degrees. my unit has a 25 degree mark so it is an early Onan. the slight advance made a big difference and timing is spot on. the unit now puts out a steady 125 volts and only wonders in tenths of volts instead of + or - 10 volts. the Onan now runs like a Swiss watch!
>
>
> What a difference a little timing makes, only RPM changes are under load changes, and she settles in right back at 125 volts even under load in about a second or 2!
>
> if you have an Onan and its running is suspect, or if it runs good enough but you want to eliminate that occasional stumble, go with a pertronix install and timing between 25-30 degrees! it fixes whats wrong with the green troll IMHO! Also now the Onan burns clean, no more stinky onan exhaust!!
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
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| Re: My Onan Runs Like sheet Episode IV: The Onan gets "Owned" [message #83902 is a reply to message #83815] |
Mon, 10 May 2010 07:50 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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Thanks for the update. I'm happy you got it fixed.
I was afraid to go to 30 degrees BTDC on the timing. I was afraid of firing too soon on cranking (starting) and also of detonation (pinging) under heavy load.
It sounds like you have neither of these. That's great
It sure is nice to get rid of those points and all of the design problems they bring with them.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: My Onan Runs Like sheet Episode IV: The Onan gets "Owned" [message #83922 is a reply to message #83815] |
Mon, 10 May 2010 10:17 |
g.winger
Messages: 792
Registered: February 2008
Location: Warrenton,Missouri
Karma: 0
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Senior Member |
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Does this now mean you are an expert and can put on a presentation at a rally??? If so I will offer my onan as a WILLING doner of said "operation". Just tring to do my part. (Hmmmmm, thinking of being a guinie pig for other presentation,,,limited slip,,disc brakes/reaction arm,,electric power brakes,,,Hmmm) PL
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| Re: My Onan Runs Like sheet Episode IV: The Onan gets "Owned" [message #83931 is a reply to message #83902] |
Mon, 10 May 2010 11:08 |
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Ken, I went with 28-30 kinda by accident. during the bracket fitting process I lost one magnent as it got launched into the next zip code, and 2 more got destroyed by coming in contact with the bracket itself! a good reason for getting a V8 pertronix is that you have more magnets, then you get with only a 4 cylinder unit!
The main issue I was having was with the clamp working its way loose by the vibration of the onan during fitting, thus causing the bracket to just touch the magnent on 2 occations. For the fourth one I finally saw where the pertronix unit was sensitive, since for whatever reason my module did not have the yellow "hot spot" that means I had to find out the hard way. I was unable to source some square tubing that Robert Mueller had recommended, so I had to settle for modding cheap framing brackets from home depot with an angle grinder. I actually did the upgrade behind the home depot because of quick access to extra meterial (I must have walked back there 6-7 times!)
Finally I just lined up the 2/5 spot in the timing hole and advanced it just a touch to what shoulda been 27* and set the bracket and pertronix right above the fin with the magnet, and punched the holes. when I bolted her up and tested the timing I found that the bracket must have moved a touch cause the timing mark was just in the corner of the timing hole. using my digital light I advanced the strobe a degee and it dissapeared behind the shroud so I arrived at around 28-30 degrees total approximate advance. I may someday put a degree wheel on the flywheel and add extra timing marks to get an exact reading, also I though of a slotted bracket to allow for timing adjustments wouldnt be a bad idea. but right now i'm just stoked that it finally runs, and runs better then it ever did! no stumbles or hunting. the nightlight in the hall ceiling outlet dosent flicker, and with my DMM in the outlets show a steady voltage at 125v to 125.5v only significant voltage variance is during load changes and then a second later it settles right back in.
The timing does not move, even under load changes, where I would guess the original points had timing literally all over the place! The mark under my timing light looked like it was jumping around constantly 10-15 degrees with the points!
Also I believe I found the source of the EMF that was freaking out my DMM, I bought a cheap magnetic supression ignition wire from Autozone, cut it to fit the Onan. basically I found a 32" wire gives enough to both cylinders. After doing this I noticed significantly less EMF as now my DMM only freaks out when right next to the Onan, rather then from some feet away! I would imagine that a good set of quality Supression wires will all but eliminate that EMF. It seems that the lack of shielding on the original wires makes a great source of "high strangeness".
FYI, new wires from Onan at my local Onan parts dealer were $17 Each!! The wire from Autozone, $4.99+ tax. The autozone cheap wire performs the task perfectly.
| Ken Burton wrote on Mon, 10 May 2010 07:50 |
Thanks for the update. I'm happy you got it fixed.
I was afraid to go to 30 degrees BTDC on the timing. I was afraid of firing too soon on cranking (starting) and also of detonation (pinging) under heavy load.
It sounds like you have neither of these. That's great
It sure is nice to get rid of those points and all of the design problems they bring with them.
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73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
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