Question on Engine Temps

[K_Arts]

Ok guys... I got a little nervous today and I'm hoping ya'll can help me calm my nerves down.



I was cruising home today on the highway (66-75mph) temp outside was in the upper 80's maybe lower 90's.



I looked down at my dash to make sure everything was ok and noticed that my engine temp was about 195*. All the way home that needle stayed where it was. Normally at about 192* my thermostat opens up and the engine temps go down to about 180 - 185*. Not this time.



First off, is this a little too warm for our trucks?



Also, My tach is reading 30,700. I'm still running the original thermostat and coolant. When is a good idea to change both out?



Thanks



Kev

 

[B.G. Smith]

Thermostat

I would guess that your thermostat is bad. The truck has enough cooling capacity that it should never get above 180 deg. unloaded. My thermostat went south when the truck was new, the rubber came loose from the valve part and restricted the water flow but I thought that problem had been corrected. You should be able to run the original coolant at least three years or 75-80 thousand miles. Just my humble opinion. bg

 

[JHansen]

Mine's been running above the 195 mark the last week or so too Kev. I'm gonna do a t/stat change and coolant flush and fill here on my next days off-assuming the problem doesn't worsen before then.



J

 

[Joel Richards]

Hey Kevin,



My truck was running a bit hotter than normal today too - of course my baby ain't used to the heat yet - he's only 5 months old.



I changed the coolant every 30k miles on my '98. Dealer said I didn't need to - so did the local shops. I didn't listen to them, and never had a problem with it - prevention is the best medicine IMO...



HTH

Joel



BTW, you gonna come play Saturday morning??

 

[JJW_ND]

Nothing hot about 195 or even 200. My personal 96 5sp never runs even close to 180 even with a trailer on (I wish it did). My work 2001 ETH 6sp is always near 190 or above. Did just under 10,000 miles in the 5 weeks with a trailer in tow most of the time. I runs 200 with pulling hard but never more and never kicks in clutch fan. Pulled 13K through many MTs in WY, ID, and MT.



Based on my 96's best MPG I believe the best engine temps is 185 - 205. 2001 stays there all the time, 1996 has made it their twice in 200K miles.



jjw

ND

 

[K_Arts]

Thanks for the reassurance guys, I really appreciate it.



Joel... since you were doing 30k changes on coolant, I take it you know how to do them. I may ask you for help in changing mine.



I was looking at mine when I got home and it was really dark and cloudy... didn't look healthy enough to drink. LMAO



I've been debating the last couple of months on whether I should have my local stealer do the work or not. I think I'll contact Genos and get a thermostat... guess it's better to be safe then sorry.



Again... Thanks



Kev

 

[jwdeeming]

Mine will run up to the redline when towing the horse trailer up to Fairplay - especially now with the warmer weather. Based on several other threads, I plan to change to the 180deg Tstat. Last summer when I thought about this, I saw them on Genos. Now I can't find the link. Guess I'll have to call them. '



It's no fun having endless power and having to back off 'cause the water overheats...

 

[illflem]

Running the A/C will raise your coolant temps a bit. 195° is nothing to worry about.

 

[K_Arts]

I don't know if it matters or not. . but the A/C wasn't turned on.



Kev

 

[RustyJC]

Ever since new ours has run about a needle-width below the 190 degF mark running empty and about a needle-width above the 190 degF mark when towing the 5ver. Outside air temps don't seem to make much difference - only in how much the fan clutch kicks in when towing up long, steep hills.



Rusty

 

[me4osu]

K_Arts-

If you do the coolant change, I recommend Shell Rotella ELC (Extended Life Coolant). It is a 600,000 mile coolant that uses an extender package at 300,000 miles. Also, it is pre-mixed and approved for all Cummins engines.

 

[K_Arts]

Rusty... you brought up an interesteing point. I'm surprised my fan clutch never engaged to cool off the engine. Hmmm makes me wonder if it even works or not. I don't ever recall my fan ever turning on since I've owned my truck.



me4osu - Thanks for that info... sounds pretty good to me. Now to see if I can locate any where I live. . LOL.



Last thing... jwdeeming also brought up an interesting tid bit of info. I went out to Geno's website last night and couldn't seem to find the thermostat listed out there. Do they still carry it? I know I need to call them and find out... . just been really busy.



Thanks



Kev

 

[jsnyder]

No fan?

I'm surprised your fan isn't kicking in. As soon as my needle goes a tick above the 190* mark the fan engages. Might want to check it.



The coolant change is easy. Don't throw away your money by letting the dealer do it. I got a t-stat from Cummins, 3 gallons of Napa coolant, and 3 gallons of distilled water for a grand total of 40 bucks or so (plus beer).



On a side note, I recently had a leak at the crimp in my radiator. The coolant would get surprisingly low, and one thing I noticed was that my temps were running higher than normal, loaded and unloaded. Usually at that point it would take 1/2 gallon or so to fill up. Check the coolant level in the radiator as well as the overflow.



Jason

 

[me4osu]

Re: No fan?

Originally posted by jsnyder

I'm surprised your fan isn't kicking in. As soon as my needle goes a tick above the 190* mark the fan engages. Might want to check it.



The coolant change is easy. Don't throw away your money by letting the dealer do it. I got a t-stat from Cummins, 3 gallons of Napa coolant, and 3 gallons of distilled water for a grand total of 40 bucks or so (plus beer).



Jason

I agree with Jason that you really should check your fan clutch. One thing that will tell you for sure is (if it ever truly gets hot in CO) you will notice your air conditioner not cooling much at all when you sit in traffic.



I can change my coolant myself, but I hate trying to find someone to take the used coolant. All I did was carry seven gallons of ELC to my local Jiffy Lube, and paid them forty buck to put it in with their machine. That way you don't have to fool with disposal, and you don't run the risk of cavitating your water pump. But, be certain to do it while it is warm outside. I had them do mine on a 45 deg day, and my T-stat would open up about every five minutes, take about a gallon, and close for another five minutes. This was idling at 2000 RPM. Took forever.

 

[JR2]

I am getting ready to swap all my rad hoses over to silicone hoses (red) so I don't have the option of using Jiffy lube. Anyone have any advice for me on how to go about swapping all the hoses and not messing up my truck. I think I may instally a 180 thermostat in there while I am at it.



JR2

 

[JJW_ND]

Everything normal!

Made another 600 mile run today with the 2001 6sp. Outside temps in the 80s, pulling 10k running 70 - 80. Ran 200 all day, on a few hills (they are pretty small in ND) temp would climb to maybe 205 or 210. Hear clutch fan once or twice. 2001s run differect from 1999 and so on. Even running this warm MPG have been 10 or better. IMHO, this is pretty good considering how hard we run these trucks.



BTW, when the clutch fan kicks in, coolant temp drops real fast to about 190 and then slowing climbs again.



Dropped trailer for last 60 miles and ran 190 degrees.



Clutch fans not kicking in until 210 is OK. If you want to see if it works, cut som cardboard to go between rad and intercooler. Have a 10" hole in center. You should here your clutch fan kick in at 210 or higher. You can't mistake if for anything else.



jjw

ND