GiraAmerica Report post Posted April 4, 2018 I have an ONAN Quiet Diesel, Model #7.5HDKAJ11451G, Serial # C000077454. While it was parked this winter I noticed coolant had leaked out. I can see coolant stains on a hose and clamp but can't tell if it came from another source higher up. Does anyone know if these units have a soft plug somewhere on the engine. Share this post Link to post Share on other sites
wildebill308 Report post Posted April 4, 2018 I would start with hose and clamps. I hear of few leaks on those units. Allso have you looked for leaks when it is running? Bill Share this post Link to post Share on other sites
manholt Report post Posted April 5, 2018 Gira. How often and long do you run generator in Winter? Share this post Link to post Share on other sites
fagnaml Report post Posted July 9, 2018 Gira -- After using my 2007 model Onan 7500 Watt Quiet Diesel generator while traveling from Houston to Fort Walton Beach Florida (and back again) this past week (July 1 - 7, 2018), a small coolant leak developed. Since my generator is not on a slide-out, it is difficult to access and thus I did not attempt to look for the leak. Could you please share the source of your coolant leak i.e. hose or clamp leak or something much worse? Did you repair the leak yourself? My generator thankfully operated without problems. I simply topped-off the coolant reservoir before making the day long drive from Fort Walton Beach back to Houston. Thanks for your thoughts. Share this post Link to post Share on other sites
