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6.5kw Gen always stumbles when running

Posted: Thu Jun 19, 2008 2:42 pm
by jwrape
F-44 motor yacht: My Dad has owned this boat for the past 7 years. The Gas Generator has always had a stumbling problem and when it's under a heavy load it smokes as well but if I just have one A/C unit on and the Fridge it runs fine and doesn't smoke.

My dad has rebuilt the heads and the carburator in hopes to fix this. It has all helped but not solved the issue. I was wondering if you guys might have some insight on what it could be?

I don't know who makes the Generator but I know it's a7.5kw and I think it's a Onan or something. Sorry for the lack of info.

Posted: Fri Jun 20, 2008 7:55 pm
by Danny Bailey
Stumbling under load is usually a sign of too lean a fuel mixture. Smoking under load is a sign of worn rings / cylinder walls.

Posted: Sat Jun 21, 2008 7:10 am
by jwrape
Danny Bailey wrote:Stumbling under load is usually a sign of too lean a fuel mixture. Smoking under load is a sign of worn rings / cylinder walls.
I figured the rings were worn. The lean situation, how would I fix that? adjust the carb?

Posted: Sun Jun 22, 2008 9:51 pm
by Safari
Be careful before you get radical. Mine was doing the same thing and worse: when a load was removed after running a while, the genny would run away; the voltage would shoot up to 166vac. Problem of smoking and stumbling was caused by a blown fuse (something with the choke). Runaway when no load was caused by the idle screw run all the way in. Another blown fuse issue caused a situation where the genny would start, run great, but would not shut down. None of these fixes were obvious.

Posted: Wed Jun 25, 2008 1:01 pm
by jwrape
Safari wrote:Be careful before you get radical. Mine was doing the same thing and worse: when a load was removed after running a while, the genny would run away; the voltage would shoot up to 166vac. Problem of smoking and stumbling was caused by a blown fuse (something with the choke). Runaway when no load was caused by the idle screw run all the way in. Another blown fuse issue caused a situation where the genny would start, run great, but would not shut down. None of these fixes were obvious.
Yea, I talked to my Dad and he mentioned it could be the points.
OH and it's not a 7.5Kw, it's a 6.5kw Onan. Where can i get Electronic Ignition for it.

Posted: Thu Jun 26, 2008 9:07 am
by jwrape
Well I just picked up a Electronic Ignition Ebay found here for $50. Hope it will correct all the issues, the Chysler 440's already have electronic ignition, the poor Gen-set needs it bad.
Image

http://cgi.ebay.com/ebaymotors/ws/eBayI ... :IT&ih=018

Posted: Thu Jun 26, 2008 9:25 am
by Safari
Great info - Thanks. I'm getting these points for mine

Posted: Thu Jun 26, 2008 9:26 am
by jwrape
Safari wrote:Great info - Thanks. I'm getting these points for mine
Cool, i figured you guys could use this. The seller is VERY helpful with questions

gen

Posted: Fri Jun 27, 2008 6:52 am
by g36
could you please post your results of the gen performance after you have installed this. also your thought on the installation instructions. thanks

Re: gen

Posted: Fri Jun 27, 2008 7:10 am
by jwrape
g36 wrote:could you please post your results of the gen performance after you have installed this. also your thought on the installation instructions. thanks
Will do. Gonna get it in the mail on Monday. Should be Tuesday or Thursday when i install it.

Posted: Wed Jul 02, 2008 5:51 pm
by jwrape
Ok, I got the unit. It's not actually the electronic ignition. The points stay in place but this works in conjuction with the point to not wear out the points. I'm a little weary of how it works, but I still need to get new points first before I install this.

Posted: Wed Jul 09, 2008 2:07 pm
by jwrape
Ok, I am sending that piece of crap back that I got off Ebay.
I finally found a article on how to upgrade to electronic igition with ONAN parts. Only catch is that it's $192 and you have to be a little handy to install it but should be pretty easy.
Here is the article for ya
http://www.gmcws.org/Tech/onan_electron ... ition.html

Image

"The electronic ignition kit (EIK), shown above, is Onan P/N 160-1376 and should be available at most Cummins Dealers and/or facilities that sell and work on Onan generators"

Posted: Wed Jul 09, 2008 3:03 pm
by Stripermann2
That's neat to know. Do you have any links on the Onan 6.5KW genny? I'm working on a MCCK series now for a freind and since Cummins bought out Onan, all they make now is diesel gennys and the web has not much info unless you purchase it...wanted a carburetor blow-up of the assembly.

Thanks.

Posted: Wed Jul 09, 2008 3:05 pm
by jwrape
Stripermann2 wrote:That's neat to know. Do you have any links on the Onan 6.5KW genny? I'm working on a MCCK series now for a freind and since Cummins bought out Onan, all they make now is diesel gennys and the web has not much info unless you purchase it...wanted a carburetor blow-up of the assembly.

Thanks.
No I didn't find anything but I do have a manual to mine, don't know if it has a carburator Blow up but I can look when I go back out to the boat in a next weekend. :wink:

Posted: Wed Jul 09, 2008 3:12 pm
by Stripermann2
Thanks the same. I have the complete manual with specs and pics for both spec A and spec B carbs. Just not very good pics...figured I could find and blow-up on the computor screen...no worries!