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Topic: coolant running a little hot - what to check and in what order? (Read 991 times) previous topic - next topic

coolant running a little hot - what to check and in what order?

My 2004 ISL engine is running a little hot.  Usually the driver information LED gauge has shown 181-185 degrees even in hot weather.  Sure it goes up a little on major hills with full load but hasn't gone into high 190's unless outside temps are really high. 
 
Now it seems it runs into low 190's when outside temps are in mid 80's and road is flat.

I have been reading the separate thread on "Cooling Questions U225" and will check the condition of the cleanliness of the radiator.

Other than dirt on the fan, the coolant level and the radiator cap, what should I check for and in what order?

Thanks as always.
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: coolant running a little hot - what to check and in what order?

Reply #1
Larry.... We have the same engine and mine runs at about 183 (Silverleaf) in summer temps and modest up and down driving with the mode switch on.  It will go up to 198 or so on steep hills such as the climb into Asheville, NC from the east.  Normally I will downshift and keep the revs/speed such that the temp does not exceed 200 on steep grades.  I did replace my radiator cap this year and keep an eye on the overflow level.  It does seem to vary more than I would expect (maybe a couple of inches).
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George Hatfield

  Never ever use World Line Motors of Nacogdoches for service!

Re: coolant running a little hot - what to check and in what order?

Reply #2
George - I have had pretty much the same experiences and used the same driving tricks but I'm concerned that the temps have recently changed.  Only thing different is that I recently added some SCA additive when the dip strips showed I needed it.
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: coolant running a little hot - what to check and in what order?

Reply #3
Only thing different is that I recently added some SCA additive when the dip strips showed I needed it.

Larry,

What coolant are you running in your 2004 and is it original?  Our '03 ISM came with ELC, which needs a test/extender addition at 3 years and a coolant change at 6 years.

It also requires chemistry-specific test strips How we replaced our anti-freeze coolant

Michelle
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: coolant running a little hot - what to check and in what order?

Reply #4
Michelle - thanks - yes it is original, a good thing to change even if it is not the problem.  My concern however is finding the magic thing that just seemed to happen all at once.  I didn't use the coach much over the winter but starting a few weeks ago the temps just jumped.

L
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: coolant running a little hot - what to check and in what order?

Reply #5
Adding SCA to an OAT-based long life coolant is a BAD move.

But, bottom line is that with 8 year old coolant, you are well-passed time to change coolant.

With your linered engine, you need to change it immediately.

Brett
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: coolant running a little hot - what to check and in what order?

Reply #6
Oh Boy  ---  gulp  ---  when you put it that way  ---  know a good place around north central New Jersey?
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: coolant running a little hot - what to check and in what order?

Reply #7
But, bottom line is that with 8 year old coolant, you are well-passed time to change coolant.

And don't forget about the generator, if it is also running the original coolant.

-M
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: coolant running a little hot - what to check and in what order?

Reply #8
I keep reading this and wondering if my ISL400 in my 2005 is operating normally or not temperature wise. 

Since I've had it (about 9 months and 6000 miles) the engine temp per the DIC warms up to about 197 and has never gone above 202 even going over the modest hills of the Smokies and 100+ degree days thru west Texas.  It has Shell Rotella ELC antifreeze (in the gennie too) and all I've done is add some when it looked a little low.

I'm going to Cummins Crosspoint for annual service in a couple of weeks so, do I need to ask about the 197-202 temperature range or just make sure it gets tested?
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Mark & Mary Benko
Former coach: 2005 U295 3823
Jeep Cherokee, Honda Fit

Re: coolant running a little hot - what to check and in what order?

Reply #9
Since my service appointment is in a week I thought I'd bump this up to see if anyone has any input.  See my previous post/question about the 197-202 temperature range.
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Mark & Mary Benko
Former coach: 2005 U295 3823
Jeep Cherokee, Honda Fit

Re: coolant running a little hot - what to check and in what order?

Reply #10
Mark,

I'd have the coolant tested and extender added if necessary.  Also ask them to verify the actual temperature versus the rating of the thermostat.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: coolant running a little hot - what to check and in what order?

Reply #11
Mark,

I'd have the coolant tested and extender added if necessary.

Unless the coolant is at its change interval.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: coolant running a little hot - what to check and in what order?

Reply #12
I think the Shell Rotella ELC change interval is 600k with an extender added at 300k.  Also, I think they call that "fill for life"?  I'm more concerned with my 2005 engine temp average about 10-15 degrees hotter that others in the posts above with 2003-2004 400 ISLs.
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Mark & Mary Benko
Former coach: 2005 U295 3823
Jeep Cherokee, Honda Fit

Re: coolant running a little hot - what to check and in what order?

Reply #13
Look for exhaust manifold leak blowing hot air onto the temp sensor. That happened to me.
1994 U280, Build 4490
Deming, NM.

 

Re: coolant running a little hot - what to check and in what order?

Reply #14
Interesting, I never get my engine temps up over 200 on any grade out east. Today I hit 215 on I  70 west of Denver. It was hot out and it is a tough hill to pull. I have hit 198 around the smokies as I live on I 81 and travel around there all the time.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon