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Topic: Radiator Lesson (Read 494 times) previous topic - next topic

Radiator Lesson

OK
Might sound dumb.....Keith told me I have a radiator leak that is common to my coach.
He suggested four bottles of a stop leak.
My question is.......
How Do You Know when radiator is "full"??
You'd a thunk I'd know this, by now.
Glenn and Amy Beinfest
2001 36' U320
#5812
2014 Honda CRV

No Whining on the YACHT

Re: Radiator Lesson

Reply #1 –
Coolant should be all the way up in the metal tank-- if you remove the radiator cap, coolant should come out.

The level is determined in the overflow container to the passenger's side.  Level hot should be above the level cold.  If it is not, you have air in the cooling system.  The system will purge itself as long as it is working properly and there is coolant in the overflow container.
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: Radiator Lesson

Reply #2 –
Thanks Brett. I never understood this before either.
Next question: How does one determine if the system is working properly?
I have a feeling that my radiator cap is not the correct one because I have had coolant come out from the cap and not go into the bottle. Maybe it was because there was no coolant in the bottle?
I just filled the bottle to the cold level and topped off the radiator and figure this is a good time to make sure everything is in order.
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: Radiator Lesson

Reply #3 –
Your cap may not be sealing properly.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Radiator Lesson

Reply #4 –
Radiator caps are not expensive, but are specific.

Hopefully, someone else with your drivetrain will have the correct PN.
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: Radiator Lesson

Reply #5 –
Quote from: wolfe10 –
Coolant should be all the way up in the metal tank-- if you remove the radiator cap, coolant should come out.

The level is determined in the overflow container to the passenger's side.  Level hot should be above the level cold.  If it is not, you have air in the cooling system.  The system will purge itself as long as it is working properly and there is coolant in the overflow container.
Brett, are you saying that the tank should be full and the overflow tank should have "some"fluid in it for the system to purge and start working properly?  My overflow tube was stopped up completely and the system was not ebbing and flowing to the tank.  All is clear now and still has not started working  back and forth to the tank.  I now have put the cold amount in the overflow and filled the tank, but have not run it since.  Hopefully when I go back tomorrow and put my new start batteries in, I can run it and see what happens when it warms up.  Of course before I do that I will have to install the resonator and exhaust back on as I had to remove the stock muffler because try as I might, I could not get the start batteries past the stock muffler.  So a small job turned into a much larger one.
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

Re: Radiator Lesson

Reply #6 –
Quote from: Herb Stark –
Brett, are you saying that the tank should be full and the overflow tank should have "some"fluid in it for the system to purge and start working properly?

YES.
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: Radiator Lesson

Reply #7 –
I worked on a coach a month ago where the hose from the black metal tank to the plastic overflow tank was totally plugged. I tried to get it cleared out, but ended up replacing the hose.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Radiator Lesson

Reply #8 –
The last time I replaced my coolant, I also replaced the radiator cap. (about 800 miles ago) I took the old cap to a NAPA store and was given what I was told was an exact replacement. After reading this post, I checked my radiator and found that is was about a gallon low even though the overflow bottle indicates full when cold.
I'll call Foretravel tomorrow to see if they have a part number for the correct cap but I found this article which will help me find the correct cap if I have to go that route. I'm pretty sure I need one with an upper seal and the one I got from NAPA doesn't have one. That would explain why the bottle system currently doesn't work and my coolant level was low.

How to Choose the Correct Radiator Cap
How to Choose the Correct Radiator Cap
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: Radiator Lesson

Reply #9 –
Also check the condition of the overflow hose carefully.  Any cracks in it will cause the system to suck air instead of fluid from the overflow as the system cools down.

This also applies to the AquaHot and the generator overflows.
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: Radiator Lesson

Reply #10 –
Quote from: Michelle –
Also check the condition of the overflow hose carefully.  Any cracks in it will cause the system to suck air instead of fluid from the overflow as the system cools down.

This also applies to the AquaHot and the generator overflows.
Michelle may have the key here. Ours also lost coolant but the solder had given up where the overflow hose fitting goes into the neck of the radiator cap housing. I  put a piece of Hardieboard above and soldered it back together.

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