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Topic: engine cooling system question/problem (Read 528 times) previous topic - next topic

engine cooling system question/problem

Good afternoon everyone,
About two months ago I posted in reference to a hose collapse in my cooling system and was told to change the pressure cap. I did and it fixed the problem. At that time I also pulled out the coolant reservoir and cleaned it out. I noticed the bottom outlet and hose to the reservoir were obstructed which i unclogged. I put the tank back in and filled it to the cold line. The black tank with the pressure cap was low on fluid but i thought the system would pull the coolant from reservoir and refill it. It did not. The coach was left in storage and now i am back at the coach.

Today I topped off the black tank with coolant, the reservoir was still to the cold line, and went for a drive at highway speeds for 50 miles. Engine temp reached 181 degrees. when i got back I checked the reservoir and it was still sitting at the cold line.  in the past i remember seeing the coolant rise to the hot line in the reservoir. I have no drips under the coach.

I checked the coolant filter shut off(don't know if that would affect anything) and it is in the "on" position which is the normal operating position in the Cummins manual

Should I change the coolant filter? Any other suggestions?

Thanks
Frank


Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: engine cooling system question/problem

Reply #1 –
First thought is that the plastic overflow tank is working and the coolant rise you expected to see is now in the black tank/coolant system as air was expelled from the system into the overflow tank.  I'd put a piece of tape on the overflow tank to mark the cold level then next couple times you drive see what it does. 
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: engine cooling system question/problem

Reply #2 –
I would replace the short, small diameter hose that goes from the black coolant tank to the reservoir.

And yes driving it several times, and let it heat up and cool down watching how the level changes.
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: engine cooling system question/problem

Reply #3 –
Let it cool and see if the black tank is still full. It won't rise in the overflow until all the air is out of the system.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: engine cooling system question/problem

Reply #4 –
Quote from: craneman –
Let it cool and see if the black tank is still full. It won't rise in the overflow until all the air is out of the system.

CORRECT.
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: engine cooling system question/problem

Reply #5 –
Thanks everyone
I'm in the process of letting the engine cool down.
I've noticed that my new radiator cap ( Napa 703-1427) is digging into the hose that goes to the reservoir which I need to put a clamp on.
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: engine cooling system question/problem

Reply #6 –
I was losing coolant and my overflow tank was not going up the the hot mark. My problem was the fitting soldered into the neck of the black tank where the overflow line goes in was loose. I put a piece of Hardiebacker Board above the tank to protect the coach, cleaned the neck and fitting with emery cloth and acid and then soldered the fitting back in place. Problem solved.

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

Re: engine cooling system question/problem

Reply #7 –
Quote from: Lt403 –
Thanks everyone
I'm in the process of letting the engine cool down.
I've noticed that my new radiator cap ( Napa 703-1427) is digging into the hose that goes to the reservoir which I need to put a clamp on.
Can you take the cap off and grind some of the lip that is contacting the hose?
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: engine cooling system question/problem

Reply #8 –
Went through this when I changed my motor, then later when I changed my water pump.

With everything full of coolant, and the engine at temp after driving, if the plastic tank is still at cold level, just fill it to hot level, then run it a while.

In the morning, the plastic tank will be close to cold.

Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: engine cooling system question/problem

Reply #9 –
Frank, do you have a stainless braid covered line that runs to your black tank with a 1/4 turn shut off?  If so you need to open the valve to allow the air to escape.  That braided line runs from the high point of your cooling system into the black tank for that purpose.  At least that's the way my '03 is.

Re: engine cooling system question/problem

Reply #10 –
Having problems w/internet

so the engine cooled down and the coolant tank was still full.
Here is a picture of the hose to the tank and how it is being dug into by the cap.
The hose is 5/16, i will buy a new piece tomorrow before i go back home.
won't know for another 2-3 weeks if its fixed.

Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH
 

Re: engine cooling system question/problem

Reply #11 –
Quote from: Lt403 –
so the engine cooled down and the coolant tank was still full.

Some prior discussion that may be of use

Radiator Reservoir Cap question  Reports of radiator caps missing gaskets, as well as making sure it's a recovery cap.
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