HDN
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I actually woke my M35A3 up from its winter slumber today to move some more big stuff from my old home. The roads were dry and looked pretty salt-free due to precipitation and melting over the past week, plus I figured on rinsing the underside of the truck with my garden hose when I was done, just in case. It started with just under 10 seconds of cranking with an outdoor temperature of 36 degrees F and no anti-gel in the fuel (added that to the fuel before my run today!).
Since I bought the truck this past late October, the tachometer would always hit 3,000 RPM when I'm going above 40 MPH in 4th gear. I intended to take it to a diesel shop or the Cat dealer to get its engine speed verified and maybe get the engine speed sensor repaired. But after about an hour and a half of idling (afraid to shut down due to charging issue) then taking it down the road, I noticed that the tach started to make sense!
I watched it as I ran the truck through its gears and it would shift into 4th at about 2,600 RPM. I really learned today how smoothly the transmission shifts when I keep the pedal close to the floor, even with the motor oil in it. Previously I would quickly let my foot off the gas pedal to force a shift between 3rd and 4th gear, but now that I know what the 4th gear shift point engine speed sounds like, I don't think I'll be doing that anymore!
I'm not yet familiar with what goes wrong with these tachometers besides some kind of magnetic sensor getting out of alignment, or something like that. I noticed that the engine built up considerable heat just idling, and when I pulled out the temperature jumped to 220 briefly and the fan kicked on. Could the sustained heat at idle have done something? Or could it be something as mundane as a loose ground? After all, the truck mostly sat for 10 years before I bought it...
Of course now that I posted this thread the tach will go bonkers again in the springtime when I will next run the truck. That's probably what will happen![Roll eyes :rolleyes: :rolleyes:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Since I bought the truck this past late October, the tachometer would always hit 3,000 RPM when I'm going above 40 MPH in 4th gear. I intended to take it to a diesel shop or the Cat dealer to get its engine speed verified and maybe get the engine speed sensor repaired. But after about an hour and a half of idling (afraid to shut down due to charging issue) then taking it down the road, I noticed that the tach started to make sense!
I watched it as I ran the truck through its gears and it would shift into 4th at about 2,600 RPM. I really learned today how smoothly the transmission shifts when I keep the pedal close to the floor, even with the motor oil in it. Previously I would quickly let my foot off the gas pedal to force a shift between 3rd and 4th gear, but now that I know what the 4th gear shift point engine speed sounds like, I don't think I'll be doing that anymore!
I'm not yet familiar with what goes wrong with these tachometers besides some kind of magnetic sensor getting out of alignment, or something like that. I noticed that the engine built up considerable heat just idling, and when I pulled out the temperature jumped to 220 briefly and the fan kicked on. Could the sustained heat at idle have done something? Or could it be something as mundane as a loose ground? After all, the truck mostly sat for 10 years before I bought it...
Of course now that I posted this thread the tach will go bonkers again in the springtime when I will next run the truck. That's probably what will happen