Overheating Issue
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Overheating Issue
Hi guys, today I was driving the 550 up a mountain pass probably around 30,000 gross. I noticed for the first time ever that the temperature gauge was climbing up towards the red mark. I was holdin the EGT's at 1250 like I always do when pulling this pass. Just about the time the needle hit the red mark, I heard the fan come on and the temps dropped down to normal but then the fan shut down and the temps climed and the process repeated.
I got to the top where there is a pull over spot thinking maybe there was something blocking the radiator, it was clear. This truck has never once had the temp gauge go much over half way and I have pulled heavier loads at higher ambiant temps then what today was.
So I'm thinking maybe it's the fan clutch? The coolant level was fine, oil level was fine, and the thermostat doesn't seem to be sticking. If anyone has had similar issues to mine could you pleas post what the solution was. Thanks guys!
I got to the top where there is a pull over spot thinking maybe there was something blocking the radiator, it was clear. This truck has never once had the temp gauge go much over half way and I have pulled heavier loads at higher ambiant temps then what today was.
So I'm thinking maybe it's the fan clutch? The coolant level was fine, oil level was fine, and the thermostat doesn't seem to be sticking. If anyone has had similar issues to mine could you pleas post what the solution was. Thanks guys!
Post Fiend
Joined: Mar 2007
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From: Texas
Lot's of radiator looking things up front. (AC, IC, then radiator) Did you check between the Intercooler and the radiator for any debris? What were the outside temps? Sounds like you heard the fan lock up and cool things back down. Coolant level still good?
The 7.3 has a pretty robust cooling system, so heating up at this time of year is not a good sign.
The 7.3 has a pretty robust cooling system, so heating up at this time of year is not a good sign.
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I just glanced at the front to see if there was some snow or ice blocking things, then popped the hood to check fluid levels and make sure all the fan blades were there. I'd guess the temp was probably around 30 or so. I hauled a heavier load last friday and had no issues, the truck sat all weekend and just started having the problem today. When on the flat ground the temp gauge stayed right around the middle...like it always does. I have to think that the viscous part of the fan has failed but I just want to be sure. The fan didn't seem to have as much noise as usual.
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I picked up a motorcraft thermostat today and am gonna change it out tomorrow. I felt the fan clutch and everything seemed normal there, no leaks, no wobble, and there was resistance when trying to spin it by hand. After driving the truck today I think that the thermostat is stuck part way open. I'll post tomorrow what I find.
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Ok, I replaced the thermostat. The old one was not stuck open but did feel like it may not open all the way. I didn't pull my trailer today but I still weighed in the neighbor hood of 15,000 lbs. I went up a 6% grade thats about 3 miles long and the temp gauge never went higher then halfway up.
Now for the weird part...Before I would have to kick the cruise control off at even the slighest hint of a hill because the EGT's would quickly climb past 1250*. Today I was able to leave the cruise on and EGT's stayed at 1200* or less even on the hill. Also before the thermostat change, I'd get a check engine light with a code of "excessive ICP" whenever I was in 6th gear and the engine would work a little, today the check engine light never came on.
So would a thermostat change affect EGT's and ICP pressure? I just lived with the ICP thing before...as in 40,000+ miles. I know the factory temp gauge probably sucks but I'm thinking that my thermostat has been screwed up for quite some time.
Now for the weird part...Before I would have to kick the cruise control off at even the slighest hint of a hill because the EGT's would quickly climb past 1250*. Today I was able to leave the cruise on and EGT's stayed at 1200* or less even on the hill. Also before the thermostat change, I'd get a check engine light with a code of "excessive ICP" whenever I was in 6th gear and the engine would work a little, today the check engine light never came on.
So would a thermostat change affect EGT's and ICP pressure? I just lived with the ICP thing before...as in 40,000+ miles. I know the factory temp gauge probably sucks but I'm thinking that my thermostat has been screwed up for quite some time.
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No kidding LOL! I only touched the three bolts holding the thermostat housing and drained and refilled the coolant. I was gonna put a wrench to all the intercooler boot clamps but didn't get around to it. But your right, that's exactly what it seems like.
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