gaylemarlowe Report post Posted April 1, 2015 I guess this is my week to get most all my questions answered. My 2005 Dutch Star with Cat C9 has always taken quite a while to get to operating temp. On a day like today, 65 deg, normal start, a few minutes to warm up then start down the road, it always takes about 25-30 minutes to get up to its max temp, which on the gauge is 210 deg. Has never gone over that even when climbing the big passes here in Colorado. I have seen quite a few of the guys write that theirs normally run around 185-190. Am I running too hot, or has Cat designed this C9 to run at that temp? Thanks Share this post Link to post Share on other sites
wolfe10 Report post Posted April 1, 2015 Analog gauges are notoriously inaccurate. So, first question is: "How long does it take for the gauge to reach the point where it stays unless you climb a long, steep grade? Is this a recent phenomenon, or has it always done this? If over 10 minutes of driving with an ambient temperature of 65 degrees F, my first suspect (and part(s) to replace) would be the thermostat(s). Caterpillar calls them "regulators". Fairly inexpensive and easy to do. Share this post Link to post Share on other sites
gbrown122 Report post Posted April 1, 2015 When I first bought my 2006 Beaver with a Cat C9, I had the same question about the operating temp. For my first service I took the coach to a Cat service center and asked about what semed to be a high temp. I was told that the C9 is designed to run at 205 to 210 degrees and that the thermostat opens at 205 degrees. My coach runs great and never gets above 210. Hopes this helps answer your guestion. Gene Share this post Link to post Share on other sites
gaylemarlowe Report post Posted April 2, 2015 Yes, this helps a lot. It has always run at these gauge temps as long as we have had it. From start up, it takes about 25-30 minutes driving on the road to get to max gauge temp. As I stated, even climbing steep grades to mountain passes, it always runs at 205-210, and going down the other side, it still shows same temp. I just assumed the cooling system was really efficient and that Cat had (hopefully) designed it to run at this temp. But, I wanted to check with you experienced guys out there.Thanks for the quick replies. Share this post Link to post Share on other sites
wolfe10 Report post Posted April 2, 2015 Two separate issues: Proper temperature for your engine. Best resource-- call the Caterpillar RV hotline with your engine serial number: 877 777-3126. Time it takes to reach operating temperature under load. 30 minutes is WAY too long. Replace the thermostat(s). Share this post Link to post Share on other sites
krivanj Report post Posted April 15, 2015 My C9 runs at 204-206 on both the analog dash gauge and on the Scangauge. By the way, trans temp also 202-206... Share this post Link to post Share on other sites
