On the road need help!

[Anthrobus]

I'm driving a 2001 bluebird freightliner Cummins 6 cylinder diesel. It weighs a little over 17,000 lb empty. We're driving through Kentucky up and down the Hills on I-65 midday and the engine is fluctuating between 200 and 220 degrees. 220° up hills and 200 degrees going down Hills . Check the fan it's running fine just had it serviced by a mechanic before we left Iowa. Ran all night in the cool weather perfectly fine. The current temperature outside right now is 90 degrees. I've been keeping it at a fairly steady 65 miles an hour. Am I running it a little too hard? Should I drop down to 55 miles per hour?

Pulled over to a flying j waited 30 min engine dropped to 170. Drove 1 mile and it shot back up to 200. Pulled off to a Walmart waiting an hour to cool. Anyone else have this problem? Should I worry?

[o1marc]

As long as it doesn't go higher it won't be critical. As long as it's going up and down it should be okay. If t starts to rise from there, shut it down and diagnose the issue.

[magnakansas]

220 degrees is upper limit but within limit. over that shut it down and let cool.

do you have a coolant overflow tank on this cooling system? can you see the level in the overflow tank? is the tank under pressure?


do not open a hot pressurized over flow tank!!!

william.

you can band aid... move wiper washer jets to in front of radiator, spray water on the radiator to help shed heat.. at 50 percent alcohol to cool even more.. again band aid..

[joeblack5]

I would hate to see 220 and for sure would slow down. what is the use of 65 if you have to stop and worry while 50 -55 will keep it at 200?

later J

[Mustng78]

You say that you had some recent service done to it? What was done? And I'm assuming your talking about coolant temp and not oil temp right?

[brokedown]

If slowing down brings your temp down, do that until you get where you're going and can spend real time diagnosing it. You may just be spinning too many RPM or going too fast with an AT545!

[Anthrobus]

Made it to Gainesville! I just drove at night when the temperature was cooler. It was still running hot at 55 mph. Speed made no difference. What's the best way to diagnose the problem? Fluids are good. Fan is running. So it's maybe the radiator or the thermostat. How do I find out?

[cadillackid]

when you say "the fan is running" is it just spinning or is it roaring like a loud jet engine when you are at 220 degrees? a viscous fan clutch.. even a bad one.. will usually let the fan spin some just not enough, you'll feel air.. but on my DEV bus when I hit the hills with my foot buried in it.. ill slowly hear that fan ramp up to a good sounding roar... and if i stop and open the hood and rev it.. its really loud till the temp drops a bit...


-Christopher

[EastCoastCB]

Originally Posted by Anthrobus

Made it to Gainesville! I just drove at night when the temperature was cooler. It was still running hot at 55 mph. Speed made no difference. What's the best way to diagnose the problem? Fluids are good. Fan is running. So it's maybe the radiator or the thermostat. How do I find out?

Yall in FL?
Hit me up if you have the time!

[Anthrobus]

Originally Posted by cadillackid

when you say "the fan is running" is it just spinning or is it roaring like a loud jet engine when you are at 220 degrees? a viscous fan clutch.. even a bad one.. will usually let the fan spin some just not enough, you'll feel air.. but on my DEV bus when I hit the hills with my foot buried in it.. ill slowly hear that fan ramp up to a good sounding roar... and if i stop and open the hood and rev it.. its really loud till the temp drops a bit...


-Christopher

Yeah we dropped a new fan clutch in and a new 180 thermostat. Still running 200 degrees but it's 100 plus here.

[o1marc]

Originally Posted by Anthrobus

Yeah we dropped a new fan clutch in and a new 180 thermostat. Still running 200 degrees but it's 100 plus here.

200 is normal operating temp if it's that hot outside, you don't have an issue

[EastCoastCB]

Originally Posted by o1marc

200 is normal operating temp if it's that hot outside, you don't have an issue

Agreed!

[djdalfaro]

When you say shut it down, I'm assuming you mean let it idle for a few minutes then shut it down, correct? To avoid wrecking the turbo...

[o1marc]

Originally Posted by EastCoastCB

Agreed!

On my trip last week running 75-80mph for 3 hours ran the temps up to 210/water, 220 Trans, but once they raised to those temps fairly rapidly, they maintained those temps at those speeds. Dropping to 70mph dropped them to 200/200. There were a couple of hills where the temp raised enough to set off the warning light and buzzer. Knowing this was a warning and still not critical, I maintained the speed to the peak where the temps drop immediately after upshifting. On a side note. I found when in cruise control at 70-75, it had to be a major grade downhill for it to pick up any speed past what it was set at.

[Miles O Roads]

May try simply washing the radiator ,sometimes that will help. I would say alot has to do with high outside temps.

[brokedown]

Driving my shortie in Valdosta today I was sitting around 185 at 55 with both air conditioners on. Above that speed my temp would have risen more than the speed.

[cadillackid]

Originally Posted by o1marc

On my trip last week running 75-80mph for 3 hours ran the temps up to 210/water, 220 Trans, but once they raised to those temps fairly rapidly, they maintained those temps at those speeds. Dropping to 70mph dropped them to 200/200. There were a couple of hills where the temp raised enough to set off the warning light and buzzer. Knowing this was a warning and still not critical, I maintained the speed to the peak where the temps drop immediately after upshifting. On a side note. I found when in cruise control at 70-75, it had to be a major grade downhill for it to pick up any speed past what it was set at.

the typical warning for the DT-466E is programmed at 228.. thats pretty critical for a DT466E.. there has been more than one case of 230 destroying the liner seals on a 466 / 466E.. while you likely didnt harm it doing it mildly once.. definitely dont make a habit of ruinning a 466 over 210-215...


to the OP, i agree with the others 200 is no big deal on a hot day..



-Christopher

[Rivetboy]

I feel at this point shooting it with an IR thermometer might be helpful to see how accurate your (guessing here) mechanical temperature instument is or how much error in your electronic instrument. Thermistors used in the sensor in the electronic version do get inaccurate over time..
Great tool to shoot your brakes with, a/c, the cat...
My Fluke and my HF cheapie read within a degree of each other and one costs a whole lot less.

[brokedown]

My HF cheapie is either unreliable or I made a mistake by not reading the directions. My reading change based on all sorts of things such as how far I am from the thing I'm pointing it at to or how long its been pointed at it. I tried to measure the clearly frigid low pressure line on one of my AC compressors and it read a temperature that was obviously off by 80 degrees or more.

[Rivetboy]

"My HF cheapie is either unreliable or I made a mistake by not reading the directions. My reading change based on all sorts of things such as how far I am from the thing I'm pointing it at to or how long its been pointed at it. I tried to measure the clearly frigid low pressure line on one of my AC compressors and it read a temperature that was obviously off by 80 degrees or more"

It would appear to me that you need a fresh battery or you have a bad one or it has suffered impact abuse who knows.
I would take a demo picture for you of mine but both of them are in the next County over in two different locations.I bought the HF because the Fluke was a long ways away and I needed a digital one day. The comparison tests were spot on within a degree over bbq one day. Oh well, who knows.
Good Luck!