Onan Adventures

I have installed several Pertronix units on several different coaches. I always check and set the timing with a light. On every one of them the
timing has been rock solid. I had one go bad. The bolts that I mounted it with loosened up and the unit eventually hit the flywheel. I now install
them with nylon lock nuts or pop rivets.

I have one to install next week for Blaine. I'll do it the same way. 26-27 BTDC and either rivets or nylon lock nuts. I'll also add a ground wire
from the Pertronix mounting frame to the bolt holding the coil in place on the engine. Is it necessary? I do not know, but I wanted to assure that
it has a good path back to the engine ground rather than rely on the sheet metal path. It only takes a minute to add the additional wire. I also
cover the wires with an additional piece of shrink tubing to prevent any chafing.

Thanks to Lawrence Gaskins for a great idea and modification.

All of them I have installed have been 100% reliable.

When I did Dan Gregg's he had a Pertronix from a VW. It also worked just fine. I just had to make a different mounting bracket.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> ,snip>
> Thanks to Lawrence Gaskins for a great idea and modification.
>
> All of them I have installed have been 100% reliable.
>
> When I did Dan Gregg's he had a Pertronix from a VW. It also worked just fine. I just had to make a different mounting bracket.

I have also installed more than a few Pertronix, some as designed and other free-lance.
When I need to put one in an unlisted application, I look at all that are available cheap on E-bay and then look at the Pertronix picture book and
decide which will be easier to modify.
It always makes little engines run better.
I usually makes little flat head engines run and start better.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
Matt, I have always modified the bracket so the magnet goes by perpendicular to the pickup unit. A week or so I saw a picture of one mounted inline
with the magnet travel. Have you ever done one this way? If so, does it seem to work just as well? I have never tried it, but it sure would make
the mounting of the 1181 easier and I would not have to bend the 1181 bracket.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
One of our Lead Stewards has a coach with a newer Onan which they just paid Cummins a GMC Unit to not fix. They tried a hitch mount with a Honda on,
but it broke and fell off (!). I told her send me some pictures and dimensions, and if it will fit, send the coach for a week and I'll stuff one of
the Chinese units in it. Or rehab the spare 6KW Onan power drawer and stuff it in.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
Last edited by a moderator:
> Matt, I have always modified the bracket so the magnet goes by perpendicular to the pickup unit. A week or so I saw a picture of one mounted inline with the magnet travel. Have you ever done one this way? If so, does it seem to work just as well? I have never tried it, but it sure would make the mounting of the 1181 easier and I would not have to bend the 1181 bracket.

My experience is that the 1181 mount is brittle - my original Pertronix installation attempt worked for a couple tens of hours and then failed when the pertronix’ aluminum bracket broke from fatigue due to wind buffeting from the flywheel airflow.

This is my original mounting arrangement that eventually failed (the last photo shows the failure):

Onan Pertronix Mount Mod I http://www.jcmco.com/gallery/Pertronix

And the second try that is still in service:

Onan Pertronix Mount - Mod II http://www.jcmco.com/gallery/PertronixModII

—Jim

Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH
 
>
> Snip
>
> My experience is that the 1181 mount is brittle - my original Pertronix installation attempt worked for a couple tens of hours and then failed
> when the pertronix' aluminum bracket broke from fatigue due to wind buffeting from the flywheel airflow.
>
> This is my original mounting arrangement that eventually failed (the last photo shows the failure):
>
> Onan Pertronix Mount Mod I
>
> And the second try that is still in service:
>
> Onan Pertronix Mount - Mod II
>
> --Jim
>
> Jim Miller
> 1977 Eleganza
> 1977 Royale
> Hamilton, OH


Jim, the above pictures did not come through. Would you please try again or send me a URL via email to click on.


Ken B.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Jim,

Now I know why none of mine ever broke: They weren't fancy enough!!! Just
an angle bracket made of whatever was handy.

Beautiful work, even if the Pertronix wasn't up to the job in the first
attitude.

Ken H.

>
> > Matt, I have always modified the bracket so the magnet goes by
> perpendicular to the pickup unit. A week or so I saw a picture of one
> mounted inline with the magnet travel. Have you ever done one this way?
> If so, does it seem to work just as well? I have never tried it, but it
> sure would make the mounting of the 1181 easier and I would not have to
> bend the 1181 bracket.
>
> My experience is that the 1181 mount is brittle - my original Pertronix
> installation attempt worked for a couple tens of hours and then failed when
> the pertronix’ aluminum bracket broke from fatigue due to wind buffeting
> from the flywheel airflow.
>
> This is my original mounting arrangement that eventually failed (the last
> photo shows the failure):
>
> Onan Pertronix Mount Mod I http://www.jcmco.com/gallery/Pertronix
>
> And the second try that is still in service:
>
> Onan Pertronix Mount - Mod II >
>
> —Jim
>
 
>
> Now I know why none of mine ever broke: They weren't fancy enough!!! Just an angle bracket made of whatever was handy.
>
> Beautiful work, even if the Pertronix wasn't up to the job in the first attitude.

Hi Ken,

Thank you for the compliment. My original Mod 0 mount was just a piece of angle bolted to the sheet metal behind the flywheel but after putting everything together I noticed that gently pushing on that sheet metal caused enough deflection that the flywheel would graze the pertronix; hence the reason for the bracket spanning two stronger bolt locations. Plus the bracket produced an awful whining sound due to the way the airflow went over it…

—Jim

Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH
 
> Matt, I have always modified the bracket so the magnet goes by perpendicular to the pickup unit. A week or so I saw a picture of one mounted
> inline with the magnet travel. Have you ever done one this way? If so, does it seem to work just as well? I have never tried it, but it sure
> would make the mounting of the 1181 easier and I would not have to bend the 1181 bracket.

Ken,

I am back and the best I can tell you is that I always try to build it so the magnet passes much as it would in the installation. Past that, I can't
more much more specific. 1181 is not a number that I usually use. I gravitate towards those that set a magnet ring over the cam and so the face is
close and the mounting height is short. Just because of my avocation and education, I try to arrange the mounting to be out of the air flow.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
Thanks Jim. That is exactly what I needed to see. The second pickup is oriented 90 degrees different than the first one and they both worked. So
either orientation will work. I think I will try turning Blaine's 90 degrees from the others I have installed.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Okay, I marked the 20 degree timing mark with a silver Sharpie and double checked the timing. What I thought was the right mark turned out to be it,
and I have the timing set at about 21 degrees advanced. You guys are right about the timing bouncing around a little bit, but it only appears to be a
degree in either direction. I'm going to call that good. The Onan is back to carrying the load of both air conditioners (original Duo-Therm units)
and the water heater without even complaining.

Thanks for all the help and advice on this. My son shouldn't have any problems with it on his trip to Colorado next week and my granddaughter should
be comfortable in the dinette with her mother going from front to rear.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
That ought to work. Good Luck.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Jim,
That is a nice install!

> >
> > Jim, the above pictures did not come through. Would you please try again or send me a URL via email to click on.
>
> Hi Ken,
>
> The one that failed:
>
> http://www.jcmco.com/gallery/Pertronix
>
> The one that has survived so far:
>
> http://www.jcmco.com/gallery/PertronixModII
>
> 73, Jim N8ECI
>
> Jim Miller
> 1977 Eleganza
> 1977 Royale
> Hamilton, OH
>
>
>
> _______________________________________________
> GMCnet mailing list
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--
JD Lisenby- USAF Ret
1978 Royale-455
Electromotive Tec2 FI & ignition

Navarre, FL
 
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