Running at higher elevations.

[Jeremy Parrett]

Climbing past Denver.CO to Colorado Springs the transmission temp rose from 175F to 190F and the engine coolant temp rose from 185F  to  200F or higher sometimes. Running the C12 at 2000 rpm or close to it to keep the radiator fan at full potential.
  We are headed through the Vail Pass etc to Moab next week.
 I am using a 7 lbs cap on the header tank.  I am going to replace it with the standard 18 lb cap.
 Is there anything else I can do to lower or better manage these  temperatures ??

[Jerry Carr]

Jeremy, I am no expert but have been told that it's better to run the CAT engine on the warm side, the Danforth valve on our C-13 is a 190 and is the same as the original one installed when the rig was new. We are running warmer with the new cooling fan/Fan motor and hdy.pump. The rig runs at 194-204 and I have seen spikes as high as 208/210 for very short periods. The folks at Massey and Dave Atherton have both told me that "hot" is in the range of 230+ and that the temps we see are normal.
If you run to cold below 180 this is not good for the CAT.
I would run your numbers past Dave he is a master CAT Mech. and should be able to help
 

[Lee Welbanks]

Jeremy,

There is nothing wrong with the temps you are running, don't mess with it. What psi cap did they spec for the cooling system, use what was spec'd when new.

[Jeremy Parrett]

Thank you Lee and jerry,
    That is very good news.   On advice I replaced the original rad cap with a 7 lb cap.  The original was 16 lbs , I will check that is correct, and replace with the correct cap for the C12.  I  replaced the Ford plastic coolant overflow tank  over a year ago with the Beaver solid steel version.  I also added a CAT 1 gallon overflow bottle.   I use CAT  ELC coolant.
   I am going to flush and refill the Cat ELC ,change the filter and if possible, replace the hoses.
 

[Lee Welbanks]

Jeremy,

Here is the fact sheet on Cat ELC coolant, you can test the ELC without having to change it out. And it takes a different filter.

[Jeremy Parrett]

Lee and Jerry,
   many thanks for your informative replies.   The CAT ELC in my C12 is 2011 vintage.  I also think the tech in Florida installed an SCA filter.  I should do a flush/refill and use a blank filter.
 We will keep an eye on the weather  next week and pick our route accordingly.

[Jerry Emert]

Lee and Jerry,
   many thanks for your informative replies.   The CAT ELC in my C12 is 2011 vintage.  I also think the tech in Florida installed an SCA filter.  I should do a flush/refill and use a blank filter.
 We will keep an eye on the weather  next week and pick our route accordingly.

Jeremy, there are posts here and a Cat procedure for changing to CAT ELC.  They suggest/specify that the filter and hoses to it be removed and plugged at the block, when using ELC.  The reason as I understand it is that the hoses are a high failure item.  If they break they empty your coolant and if you don't notice it you may do damage to your engine.  Gerald Farris is one of them that has addressed it a few times.  I just had it done a couple months ago and it cost 700.00 for a shop to do the job.  I'm a newbie so check out the posts.  Hope this helps.
Jerry

[Jeremy Parrett]

Jerry,
  our C12 has Cat ELC from 2011 .We switched from green goop  filled with in Ensenada .Baja. Mexico after a hose blew.
 The hose that fractured was a feed off the manifold to a T probably going forward to the dash heater.  It had chafed on the transmission bracing strut.  The hoses that run off this manifold to the filter on my coach are replaced with metal pipe around the C12.  I will ask the tech what is involved to just disconnect the metal pipes and install 2 brass plugs.  I can remove the filter housing and lines at a later date.
   Thanks for the heads up.

[Joel Ashley]

Have to agree with Jerry and Lee... those temps are perfectly normal as is.