engine temp concerns
#1
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Hey, my '99 diesel has been running kinda high in the temp area....usually right at the upper end of the "safe" or operating range on the gauge. It has been there with an empty truck @ 80 mph with the ac on a 102 degree day. It will also get there pulling a 6,000# load on flat roads @ 60 mph when its 70 degrees out. The strange part is when I slow down for a stop sign the temp falls right down to slightly below 190 but climbs right back up at speed. What is an acceptable temp to let the cummins get to? I plan on back-flushing the radiator(inside and out)and probably replacing the clutch fan for starters. Maybe a new thermostat as well. Any suggestions or past experiences that you can share would be appreciated! Thanks in advance!!
#2
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Mine runs about 190 or a tick above on hot days, but I just cleaned my radiator out cause it ran about 220 one day pulling a steel trailer. Might see if you can blow it out some and see how that helps. I've been lookin at a chip cause a friend said his Edge made his engine run alot cooler than normal.
#5
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Check the outlet neck temp with an ir temp gun (gauge could be off a little). Does the engine fan come on? you should be able to hear it. If it doesn't kick on, then your gonna need a fan clutch.Next take a low pressure water hose and wash the radiator out from both sides. A lot of road debris can get in the fins. When was the last time you changed your coolant? if it's been more then 2 yrs go down to a truck shop (tractor trailer shop, not shucks or napa) and get yourself some good coolant. The difference is the napa/ automotive stuff only last 2yrs and the semi truck stuff last for 6yrs. Yes it cost more but you get a beeter product. I run fleetrite coolant. I believe its called fleetrite ES complete. Comes with sca's/dca already in it, just mix with water at 50/50. Do not use extended life antifreeze (the red stuff) on the older cummins (2002 and older) the gaskets weren't designed for it and will leak.