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Topic: Overflow bottle? (Read 502 times) previous topic - next topic

Overflow bottle?

Hello everyone....hope all had a great Thanksgiving!  I have had to add coolant to the white bottle in the picture 3 times since purchasing the coach in May....(about 2000 miles traveled). Is this normal? My good bud says this looks to be an overflow for the overflow (black steel box to the left of the white)....I look forward to learning what this is and what to do with it!  Thanks
Dave
2002 295 36'
Build 6006
Motorcade Member 17931
Toad 2003 Jeep Wrangler
2008 BMW R1200 GSA

Re: Overflow bottle?

Reply #1 –
The black box is pressurized and the white bottle is the overflow. If you are having to add coolant you have a leak.
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: Overflow bottle?

Reply #2 –
It will fill up when engine is warm and go down when engine is cold. Fill to low mark when cold.
Should be there every morning when cool.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Overflow bottle?

Reply #3 –
Quote from: craneman –
The black box is pressurized and the white bottle is the overflow. If you are having to add coolant you have a leak.
That's what I was afraid of...so the leak could be a hose, a leak in the bottle itself, big hose, little hose, decayed gasket somewhere....am I on the right track?
Dave
2002 295 36'
Build 6006
Motorcade Member 17931
Toad 2003 Jeep Wrangler
2008 BMW R1200 GSA

Re: Overflow bottle?

Reply #4 –
Quote from: jcus –
It will fill up when engine is warm and go down when engine is cold. Fill to low mark when cold.
Should be there every morning when cool.
I figured it was like a car in that respect...my concern is over the course of a 18 hour drive the fluid lost is the equivalent to the amount from the "cold" line to the bottom of the bottle....coach will loose that amount.
Dave
2002 295 36'
Build 6006
Motorcade Member 17931
Toad 2003 Jeep Wrangler
2008 BMW R1200 GSA

Re: Overflow bottle?

Reply #5 –
Quote
That's what I was afraid of...so the leak could be a hose, a leak in the bottle itself,

Those overflow containers get brittle and crack with age. I had to replace mine a couple of years ago. You can get an exact replacement from Foretravel.
jor
93 225
95 300
97 270
99 320

Re: Overflow bottle?

Reply #6 –
Until you find the leak, check your oil dipstick regularly.  If oil level grows and it becomes "milky" looking stop running the engine.  Also check transmission dipstick - the cooling system for the transmission has coolant as cooling system.

Edit: Also remove radiator cap (on black metal tank) when engine and tank is cool. Check gasket on cap for cracking and seal.  Push down to remove and to reinstall.

Probably not leaking from the head gasket into the engine - but be safe and check dipstick every time after you run the engine.

With engine running look under coach, around lines, and under bottle for any drips. 
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Overflow bottle?

Reply #7 –
Quote from: dke1955 –
I figured it was like a car in that respect...my concern is over the course of a 18 hour drive the fluid lost is the equivalent to the amount from the "cold" line to the bottom of the bottle....coach will loose that amount.
I would make sure steel tank is full, [check when cool] fill plastic tk to lower line and run down the road a couple hours, get your old clothes on and a good flashlight and then start looking, better chance of seeing leak when under pressure. Assuming you checked  the cap for pressure when hot?
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Overflow bottle?

Reply #8 –
Check the easy stuff first - and think positive!

Could be something as simple as a loose hose clamp...if you're lucky.  I usually get a couple little leaks each year when the first really cold weather hits.  Soon as I notice them, and tighten them up, they're good for the rest of the Winter season.

Check anywhere in the engine compartment where your radiator hoses are clamped.  Also up front in the vicinity of the dash heater/air conditioning unit.  Check in your water heater bay, if you have the Motor Aid feature on your hot water heater.

Take the coach out for a drive, get everything up to operating temps, run the dash heater, then try to park on some clean cement pavement for a couple hours.  Watch for small tell-tale puddles of coolant under the coach.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Overflow bottle?

Reply #9 –
Thanks to all for the replies!...as always great useful information.
Happy Holidays!
Dave
2002 295 36'
Build 6006
Motorcade Member 17931
Toad 2003 Jeep Wrangler
2008 BMW R1200 GSA

Re: Overflow bottle?

Reply #10 –
It has been mentioned already, but I want to emphasize:  If the level of coolant in the overflow reservoir does not change between hot engine and cold engine, THERE IS AIR IN THE COOLING SYSTEM. That air is absorbing the expansion upon heating.  If only liquid in the system, it WILL flow into the overflow reservoir as temperature of coolant rises and will be sucked back into the cooling system as it cools.
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: Overflow bottle?

Reply #11 –
Make sure the cap is vented on overflow bottle.  I chased loss of antifreeze until I read on forum the cap has to be vented.  Drilled small hole in cap and no more adding antifreeze. I had lost original cap.
Never could find where antifreeze was going.

Larry Bradley
1998 U 270
Larry Bradley
SOB
former 1998 U270
Build 5251
Jeep Grand Cherokee