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Topic: Cummins ISL cooling system - overflow empty (Read 1868 times) previous topic - next topic

Cummins ISL cooling system - overflow empty

Did my usual check on levels tonight and noticed the coolant ( pink ) expansion tank was empty , took pressure cap off metal tank and it was half empty !

1. Looked for signs of leak and found nothing
2. Topped up with plain water ( mistake ??)
3.  pressure cap rubber seal looks perished will replace ASAP

Had oil and filter change a few days ago , maybe tech checked but didn't seal properly ?
Since have noticed dash air blowing hot then cool as if air trapped ?
Any advice appreciated , I am 1000 miles from home heading to Florida .
So feeling very uneasy
Jimmy
2003 U295 3620

Re: Cummins ISL cooling system - overflow empty

Reply #1 –
Jimmy, should of topped off with distilled water at least or better yet, 50/50 mix of coolant.
 If you have aqua hot, check hoses and pipes around the unit.
 It sounds like the cap is the issue.
 Good luck!
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Cummins ISL cooling system - overflow empty

Reply #2 –
Jimmy,

I had an issue with the overflow tube from where it comes out of the filler/cap neck over to the catch tank. The brass fitting the rubber hose fits onto came unsoldered from the neck and when the black coolant tank filled when the engine was warm, the excess just flowed out instead of over to the catch tank. Ours has a sensor about half way down on the tank. When the liquid goes below the sensor, the engine goes into shut down mode or if not running, it won't allow the engine to start. The brass fitting was just barely into the neck and I was surprised it held 20 years.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Cummins ISL cooling system - overflow empty

Reply #3 –
Thanks guys , just spent an hour at autozone trying to cross reference then opening every cap box they had , no luck so going to try napa in morning .
Looked at the antifreeze mix and  only one met the spec in manual .
What do you guys use
Jimmy
2003 U295 3620

Re: Cummins ISL cooling system - overflow empty

Reply #4 –
Quote from: Jimmyjnr –

Looked at the antifreeze mix and  only one met the spec in manual .
What do you guys use

In 2003 your coach probably came with Rotella ELC as standard.  If you were still on the original coolant, you're a little overdue for a flush n' fill anyway.  Genset should have the same coolant (and need a flush/fill as well).

We had to replace genset overflow hose and rad cap last year as well due to cracks in both.  Might not be a bad idea to do both systems at the same time.
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: Cummins ISL cooling system - overflow empty

Reply #5 –
You'll need a truck parts house to find that radiator cap in stock.  Some NAPA's are, but most aren't.
Regards,
Brett

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

Re: Cummins ISL cooling system - overflow empty

Reply #6 –
Howdy Jimmy,
This is the p/n for our '00 U320 ISM450 :  Radiator Cap NAPA 703-1427
Good Luck, Dave A
Dave and Nancy Abel
'00 U320 36' WTFE  Build #5669
'10 Jeep Wrangler Unlimited Rubicon
Livingston, TX  SKP's Fulltiming

Re: Cummins ISL cooling system - overflow empty

Reply #7 –
With the Cummins sleeved engine, correct coolant and coolant change intervals is a critical element in engine life.  According to my engine manual, coolant should be changed every two years max.  Failure to do so can cause pitting of cylinder liners and engine failure.  Really important stuff.  Once the liners are pitted, the only remedy is engine overhaul with replacement liners--- very expensive!
Current coach 1996 U320 40'
Previous coach, 1990 36' U280

Re: Cummins ISL cooling system - overflow empty

Reply #8 –
Quote from: Kemahjohn –
According to my engine manual, coolant should be changed every two years max. 

Not sure what engine you have in your coach.  Jimmy's 2003 Cummins ISL was most likely delivered with ELC coolant and per Cummins, test at 3 years, add extender if indicated, change at 6 years.  ELC (extended life coolants) are different than "regular" coolants. 

A number of threads on the forum discussing ELC (look for spike45's posts; he was a Cummins fluids engineer).  Brett Wolfe has some excellent posts on the subject and on coolants in general as well.
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: Cummins ISL cooling system - overflow empty

Reply #10 –
Thanks to everyone for input , I eventually located a new cap (30miles away) and replaced it this afternoon and yes when I lifted engine cover to let system cool I could see the drip from the low edge of the cap !
I have driven south to chattanooga and hope to speak to a cummins service shop tomorrow about a flush and refill. A large diesel service center quoted "around"$250
Jimmy
2003 U295 3620

Re: Cummins ISL cooling system - overflow empty

Reply #11 –
Quote from: Jimmyjnr –
hope to speak to a cummins service shop tomorrow about a flush and refill. A large diesel service center quoted "around"$250

Make sure they are doing an ELC coolant at that price (like Rotella ELC).

We paid $16.32/gallon in 2012 for Rotella ELC (not the 50:50dilute), Kino Oil in Fredericksburg, TX.  According to Barry's site, a 2003 ISL coolant capacity is 15 gallons of 50:50 mix.  7.5 gallons of ELC would be $122.40 just for the coolant.  Around $250 would be very reasonable for a flush n' fill with new coolant filter and ELC.
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: Cummins ISL cooling system - overflow empty

Reply #12 –
My overflow tank was empty or nearly so and when the engine was cold I still has some pressure in the systen.  Cummins checked it out on my last service and said the hose from the cap neck to the overflow tank was plugged up.  I didn't ask with what.  They cleaned it out, added 1/2 gallon of premix coolant, checked the chemistry and said I was good to go.  Overflow jug is now doing just what I expect.

Roger
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Cummins ISL cooling system - overflow empty

Reply #13 –
Cummins shop quoted $350 flush , elc , filter .
Jimmy
2003 U295 3620

Re: Cummins ISL cooling system - overflow empty

Reply #14 –
Quote from: Jimmyjnr –
Cummins shop quoted $350 flush , elc , filter .

Jimmy,

Are you a Cummins Powerclub member?  Home Page || Cummins Power Club - The Power To Keep You Moving  Save 10% on parts and service at a Cummins location.  $19.95 for an annual membership. 
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: Cummins ISL cooling system - overflow empty

Reply #15 –
As always Michele , you are a star
Jimmy
2003 U295 3620

Re: Cummins ISL cooling system - overflow empty

Reply #16 –
Thanks Jimmy, but I can't take credit.  We learned about the Cummins Powerclub from George Stoltz.
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