Powered by Blogger.
We are saddened to announce the passing of Gary Bunzer on April 17, 2020. We hope the RV Doctor website will continue to provide helpful information for you. Thank you for your interest and support for the RV Doctor - Debbie, Heather and Gretchen

Friday, October 23, 2009

Gen No-Start

I have a 6,500-watt gas Onan generator that starts and runs on the starter but quits when you release the switch. I have tuned it up, replaced the fuel pump (not up to par) and after much searching, found the specifications for the points, etc. Does this engine have a ballast resistor (like the old Dodge chassis’)? And where would it be located, in the coil.
Larry, (Avon Park, FL)

Larry, I haven’t seen this problem in quite some time. Indeed there is a resistor in that start circuit that, if faulty, will result in your specific symptom. On newer units that symptom usually means a circuit board is faulty, but on your unit there is a resistor located on the generator end (the right-hand side) of the unit as it’s positioned in the compartment. There is a removable shroud covering the brushes and other generator components on that right-hand side. Disconnect the battery to the generator and look under that shroud. You should see a metal spring clasp that holds the shroud in place. Release the clasp and the shroud can either be lifted off the unit or slid to the right to gain access to the resistor. The resistor is located under the upper support bracket closest to you. It will have two spade connectors on it. It will be necessary to remove the resistor (one long screw through the center) and replace it with one of the same rating. Your parts book for that generator should reveal the actual part number you need. I’ve never fully understood why this resistor burns out periodically, but a new one will have you cranking that unit in no time.


In all instances, every effort is made to ensure the correctness of all content on the RV Doctor Website. It is imperative that if you choose to follow any instructions or procedures outlined on any page of this website, you must first satisfy yourself thoroughly that neither personal nor product safety will be compromised or jeopardized.

All rights reserved.

If you are in doubt or do not feel comfortable about a procedure, do not continue. Simply call your local RV service facility and make an appointment with them. The advice, recommendations and procedures offered by the RV Doctor are solely those of Gary. They do not necessarily reflect the opinions, procedures and recommendations of our sponsors or advertisers.