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Topic: Coolant overflow bottle on a u320 (Read 367 times) previous topic - next topic

Coolant overflow bottle on a u320

Since I cannot read the hot and cold full marks on the bottle is there anyone with a similar bottle that could tell me how many inches above the bottom those marks should be?
George Mann
2002 U320 #5934
2017 Rubicon
2013 BMW GS
Waterford MI

Re: Coolant overflow bottle on a u320

Reply #1 –
George,

The exact location of the cold/hot level marks is not that critical.

Absolutely if you have a coolant level sensor, the cold level needs to be several inches above it.

And, as long as the hot level with engine fully warmed up (like check at top of hill at a rest area-- engine still going so you don't hurt the turbo) you need around 3" from overflowing.

Another check that is often ignored if one sees coolant in the reservoir is that the level DOES change between when the engine is cold or hot.  If it doesn't change, there is an air pocket in the cooling system.  Could be ounces, could be gallons.  If the overflow level stays the same hot/cold, with engine cold, remove the radiator cap (push down firmly and rotate counterclockwise).  Coolant should be right up to the brim.
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 overflow bottle on a u320

Reply #2 –
Quote from: wolfe10 –

Another check that is often ignored if one sees coolant in the reservoir is that the level DOES change between when the engine is cold or hot.  If it doesn't change, there is an air pocket in the cooling system.  Could be ounces, could be gallons.  If the overflow level stays the same hot/cold, with engine cold, remove the radiator cap (push down firmly and rotate counterclockwise).  Coolant should be right up to the brim.

Also note that if there are any cracks in the overflow hose or an issue with the radiator cap, air will be sucked in vs. coolant from the overflow tank.  The correct radiator cap in this application is a recover style.
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 overflow bottle on a u320

Reply #3 –
Full cold is about the bottom of the label on the plastic bottle. The metal tank must be full to the top when cold. Your level in the plastic tank looks ok if the motor is cold
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Coolant overflow bottle on a u320

Reply #4 –
If the engine is cold in the picture the level is perfect.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Coolant overflow bottle on a u320

Reply #5 –
The overflow bottle was empty.  I filled it to that level so I can warm up the engine to change fluids (oil, then coolant).  I will be doing a full coolant flush (Fleetguard Restore), changing hoses and refilling with Fleetguard Compleat OAT (as recommended by others on the forum) and using a vacuum fill tool on the advice of DSD.  I have some leaking of coolant at the trans cooler rubber hose connection.  Hopefully it's the old hose and/or hose clamp and not the cooler itself.  Also the 5/16" tubing from radiator neck to overflow bottle is suspect and I have new tubing for that as well on  the recommendation of Michelle.  I'm thinking I should replace the thermostat while I'm at it.  Can anyone comment as to the difficulty of that task on the ISM?  Thank you to everyone on the forum for all of the good advice and information they have provided on many of my projects.
George Mann
2002 U320 #5934
2017 Rubicon
2013 BMW GS
Waterford MI

Re: Coolant overflow bottle on a u320

Reply #6 –
George,

While you are doing all that you might think about removing the radiator top tank (the square black one next to the overflow) and clean and paint. I added some stand off spacers so the tank back will have some air space where it can dry and not sweat between the back and the mounting plate.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Coolant overflow bottle on a u320

Reply #7 –
Pic attached, 2003 U320:
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Coolant overflow bottle on a u320

Reply #8 –
quote;
While you are doing all that you might think about removing the radiator top tank (the square black one next to the overflow) and clean and paint. I added some stand off spacers so the tank back will have some air space where it can dry and not sweat between the back and the mounting plate.

Good advice.  I have read about that on some other posts to the forum and I will plan to do that as well... So much to do, so little time.
George Mann
2002 U320 #5934
2017 Rubicon
2013 BMW GS
Waterford MI

Re: Coolant overflow bottle on a u320

Reply #9 –
Mine was almost rusted through cleaned it up painted it and added stand off washers. I know a couple of other folks that found theirs the same way.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Coolant overflow bottle on a u320

Reply #10 –
I did that to mine also!
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Coolant overflow bottle on a u320

Reply #11 –
Quote from: Geodmann –
The overflow bottle was empty.  I filled it to that level so I can warm up the engine to change fluids (oil, then coolant).  I will be doing a full coolant flush (Fleetguard Restore), changing hoses and refilling with Fleetguard Compleat OAT (as recommended by others on the forum) and using a vacuum fill tool on the advice of DSD.  I have some leaking of coolant at the trans cooler rubber hose connection.  Hopefully it's the old hose and/or hose clamp and not the cooler itself.  Also the 5/16" tubing from radiator neck to overflow bottle is suspect and I have new tubing for that as well on  the recommendation of Michelle.  I'm thinking I should replace the thermostat while I'm at it.  Can anyone comment as to the difficulty of that task on the ISM?  Thank you to everyone on the forum for all of the good advice and information they have provided on many of my projects.
Be sure that the tubing from the radiator cap overflow to the tank is not stopped up.  Mine was.  I do not know what had filled it up, but I had a hard time clearing it out.  And be sure to add coolant to the tank, if empty it will not work properly.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said